KR102173739B1 - Titanium based uv sensing wire and device comprisng the uv sensing wire - Google Patents

Abstract

The present invention relates to a method of manufacturing a light-sensing wire, and the like, comprising: a primary treatment process of preparing a primary treatment base material, which is a base base material whose outer surface is etched by treating a base base material containing titanium with an acid solution; A secondary treatment step of oxidizing the primary treatment base material to prepare a secondary treatment base material having a controlled surface roughness; A chemical treatment process of preparing a chemically treated chemical treatment substrate by immersing the secondary treatment substrate in a titanium precursor solution; And a heat treatment process of heat-treating the chemically treated substrate to prepare a light sensing wire including a titanium dioxide substrate layer including a titanium dioxide nanostructure on the base substrate.

Description

Manufacturing method of titanium-based light sensing wire and light sensing device {TITANIUM BASED UV SENSING WIRE AND DEVICE COMPRISNG THE UV SENSING WIRE}

The present invention relates to a method of manufacturing a titanium-based light-sensing wire and a light-sensing device, and a titanium-based light-sensing wire that can be manufactured to the thickness of a human hair having a flexible or non-flexible characteristic using a modified chemical oxidation method, and a battery using the same It relates to an optical sensor manufactured to be able to be driven without.

The technology of growing nano-class semiconductor materials on a substrate having various properties such as flexible or non-flexible is a technology field that is increasing interest because it can be used in various ways in biomedical and textile industries.

Changes in the functional properties of nanoscale materials can be adjusted according to various variables such as conditions of the growth process, composition of the material to be deposited, surface morphology, thickness of the coating material, and the type of substrate used for growth. Among these, the growth process and the type of substrate play an important role in obtaining desirable characteristics such as improved technical characteristics, flexibility/durability and cost efficiency required for application to real-time application equipment such as sensors, energy harvesting equipment, and security equipment. do.

Recently, applying the hydrothermal method to the growth of piezoelectric/ferroelectric films has cost advantages, eco-friendly properties, low process temperatures, properties that can control the shape of nanomaterials, and applied to organic printed circuit boards in the synthesis process. It is gaining interest for reasons such as the characteristics that it is suitable for.

Growth and functional properties of nanostructures are SrTiO ₃ , MgO, glass, LaAlO ₃ for non-flexible substrates, and Ni/Cr metal foil, Ti/Al/kapton, ITO/PET (Indium Tin Oxide/Polyethylene terephthalate) for flexible substrates. ), silicon, and carbon fiber. Development of methods for growing various types of substrates and nanostructures enables micro/nano electronic equipment with excellent performance and improved mobility/durability while reducing the device active area area and having a curved (non-planar) mechanical structure. Can increase the possibility of development. In addition, research on these materials can be applied to various fields such as wearable energy harvesters, self-powered sensors, implantable biomedical devices, and security systems.

Domestic patent application No. 10-2010-0098331, Flexible nanogenerator manufacturing method and flexible nanogenerator manufactured thereby Domestic Patent Application No. 10-2010-0019499, UV sensor manufacturing method and UV sensor using ＺnO nanowires

An object of the present invention is to provide a titanium-based light sensing wire that can be manufactured to the thickness of a human hair having a flexible or non-flexible characteristic using a modified chemical oxidation method, and an optical sensor manufactured to be driven without a battery using the same.

In order to achieve the above object, the manufacturing method of a light sensing wire according to an embodiment of the present invention is to prepare a primary treatment base material, which is a base base material with an external surface etched by treating a base base material containing titanium with an acid solution. Primary processing; A secondary treatment step of oxidizing the primary treatment base material to prepare a secondary treatment base material having a controlled surface roughness; A chemical treatment process of preparing a chemically treated chemical treatment substrate by immersing the secondary treatment substrate in a titanium precursor solution; And a heat treatment process of heat-treating the chemically treated substrate to prepare a light sensing wire including a titanium dioxide substrate layer including a titanium dioxide nanostructure on the base substrate.

The acid solution applied in the first treatment process is oxalic acid, lactic acid, citric acid, malic acid, acetic acid, tartaric acid, and Dipic acid, succinic acid, maleic acid, glutamic aicd, fumaric aicd, pyruvic aicd, gluconic acid, satric acid ctric acid), aspartic acid, and terebic acid. It may be a weak acid solution selected from the group consisting of.

The weak acid solution may be a weak acid aqueous solution of 1 to 10% by weight.

The chemical treatment in the chemical treatment process may be performed at a chemical treatment temperature of 70 to 110 °C.

Oxidation in the secondary treatment process may be performed by immersing the primary treatment substrate in a hydrogen peroxide solution.

The heat treatment in the heat treatment process may be performed at 400 to 600°C.

The base material may be in the form of a wire having a diameter of 1,000 μm or less.

Another light sensing device according to another embodiment of the present invention includes: a support substrate; A light sensing wire positioned on the supporting substrate and including a titanium dioxide substrate layer including a wire-shaped basic substrate containing titanium and a titanium dioxide nanostructure grown on the basic substrate; And a connection structure for connecting the light sensing wire to an external display device.

The light sensing device may react to ultraviolet rays.

The base material is flexible, has a diameter of 500 μm or less, and the light sensing wire may be flexible.

The basic material has a diameter of more than 500 μm, and the light sensing wire may operate at a bias voltage of ±3 V or more.

100, 800 ㎛, L ≤6 cm)을 활용한 티타늄-이산화티타늄 나노구조체에 대하여 개시한다. 또한, 이러한 소재가 베터리 없이 구동될 수 있는 센서 등에 활용될 수 있다는 점을 실험적으로 확인했다. 플렉서블 또는 논플렉서블 티타늄 와이어 상에 나노재료를 반경방향 성장(radial growth) 시킨 재료를 열처리하는 등의 방법으로 반응을 진행하여 비용효율을 높이면서도 고 기능성 재료를 제공할 수 있다는 점을 실험적으로 확인했다.The inventors of the present invention, as a high-performance nanomaterial without added lead, is a metal titanium wire (Ø

100, 800 µm, L ≤ 6 cm) is disclosed for a titanium-titanium dioxide nanostructure. In addition, it was experimentally confirmed that these materials can be used for sensors that can be driven without batteries. It was experimentally confirmed that a high-functional material can be provided while increasing cost efficiency by performing a reaction by heat treatment of a material obtained by heat treatment of a material obtained by radially growing a nanomaterial on a flexible or non-flexible titanium wire. .

800 ㎛과 100 ㎛의 직경과 L

6 cm의 길이를 갖는 플렉서블 티타늄 와이어(Ti wire)로 급속하게 성장시켰다. Ø

800 ㎛인 TiO₂ NSs/Ti wire의 경우 유연성이 상실되어 플렉서블 에너지 하베스팅(또는 센서) 장치에 적용하기에 적합하지 않으나, 광 센서 등의 자가전원으로 활용도가 우수했다. 제조된 금속(Ag)-반도체(TiO₂ 와이어)-금속(Ag) 장치는 다양한 파장(365 nm, 405 nm 또는 535 nm)과 강도의 광원 하에서 테스트되었는데, TiO2 NSs/Ti wire (Ø

800 ㎛)는 UV 센서 (TW-UV 센서)에 적용되어 TW-UV 센서 (Ø

100 ㎛)와 비교해 낮은 바이어스 전압에서도 좋은 반응성을 나타냈다. 라만 분석(Raman analysis) 결과, TiO₂는 아나타제 상(anatase phase)으로 확인되었다.Specifically, the inventors of the present invention have developed various TiO ₂ nanomaterials (TiO ₂ NSs) such as nano needles and nano particles, respectively.

800 μm and 100 μm diameter and L

It was rapidly grown into a flexible titanium wire (Ti wire) having a length of 6 cm. Ø

In the case of 800 ㎛ TiO ₂ NSs/Ti wire, it is not suitable to be applied to flexible energy harvesting (or sensor) devices due to loss of flexibility, but it has excellent utility as a self-powered power source such as an optical sensor. The manufactured metal (Ag)-semiconductor (TiO ₂ wire)-metal (Ag) device was tested under light sources of various wavelengths (365 nm, 405 nm or 535 nm) and intensities, and TiO2 NSs/Ti wire ( Ø

800 ㎛) is applied to the UV sensor (TW-UV sensor) and the TW-UV sensor ( Ø

100 μm) showed good reactivity even at a low bias voltage. As a result of Raman analysis, TiO ₂ was identified as an anatase phase.

This invention is highly applicable to micro/nano devices having a non-planar mechanical structure, and can be used for self-powered UV sensors that can be implemented as thin as a human hair.

Hereinafter, the present invention will be described in more detail.

A method of manufacturing a light sensing wire according to an embodiment of the present invention includes a primary treatment process of preparing a primary treatment base material, which is a base base material whose outer surface is etched by treating a base base material containing titanium with an acid solution; A secondary treatment step of oxidizing the primary treatment base material to prepare a secondary treatment base material having a controlled surface roughness; A chemical treatment process of preparing a chemically treated chemical treatment substrate by immersing the secondary treatment substrate in a titanium precursor solution; And a heat treatment process of heat-treating the chemically treated substrate to prepare a light sensing wire including a titanium dioxide substrate layer including a titanium dioxide nanostructure on the base substrate.

The base material is a non-flexible or flexible material that acts as a support for a series of processes of forming a titanium dioxide nanostructure, and, for example, a titanium wire, a titanium alloy wire, or the like may be applied.

The primary treatment process is a process of cleaning and etching the outer surface of the flexible base material to improve adhesion or coating properties.

The acid solution applied in the first treatment process may include carboxylic acids or dicarboxylic acids. Specifically, the acid solution applied in the first treatment process is oxalic acid, lactic acid, citric acid, malic acid, malic acid, acetic acid, and tartaric acid. , Adipic acid, succinic acid, maleic acid, glutamic aicd, fumaric aicd, pyruvic aicd, gluconic acid, sat It may be a weak acid solution selected from the group consisting of ctric acid, aspartic acid, and terebic acid.

If the weak acid solution mentioned above is applied as the acid solution applied in the first treatment process, compared to applying a strong acid such as hydrochloric acid, the outer surface of the base material can be etched and carried out efficiently under mild conditions. At this time, the weak acid solution is preferably a weak acid aqueous solution of 1 to 10% by weight is applied.

As the weak acid solution, an oxalic acid solution is preferably applied, and specifically, 1 to 10 wt% of an oxalic acid aqueous solution can be applied, and in the case of such treatment, sufficient etching effect without impairing the properties of the base material under mild conditions At the same time, it is possible to apply a simple washing process and the like, so that sufficient effects of the process can be obtained, and at the same time, it is advantageous in achieving process efficiency.

The first treatment process may be performed at a first treatment temperature of 60 to 140° C. for a first treatment temperature of 15 minutes to 5 hours, and when the reaction proceeds at such a first treatment time and a first treatment degree, sufficient etching While obtaining the effect, the primary treatment process can be carried out efficiently.

Oxidation in the secondary treatment process may be performed by a method of oxidizing the surface of the first-treated substrate by chemical or physical methods.

Oxidation in the secondary treatment process may be performed by applying a strong oxidizing agent including oxygen, ozone, or hydrogen peroxide, and specifically, may be performed by immersing the first treated substrate in a hydrogen peroxide solution. In the case of performing the secondary treatment with the hydrogen peroxide solution, the titanium wire pretreated with the weak acid solution is oxidized to obtain a greater number of electrons, and the concentration of the strong oxidizing agent and the oxidation time in the secondary treatment are adjusted. The surface roughness or thickness of the oxide layer can be adjusted.

In the secondary treatment, the surface roughness is treated with the acid strong oxidizing agent mentioned above, so that the surface roughness and the thickness of the oxide layer can be adjusted according to the treatment time and concentration. For example, when treated at 30 wt% for 1 to 6 hours, a nanometer-level surface roughness can be obtained, and when treated for 24 hours or more, a micrometer level surface roughness can be obtained.

The titanium precursor solution may be applied as a solution of any one titanium precursor selected from the group consisting of TiCl ₃ , TiCl ₄ , C1 ₂ H ₂₈ O ₄ Ti, and combinations thereof. This titanium precursor solution makes it possible to stably proceed to the process of generating titanium dioxide nanostructures that proceeds later.

The titanium precursor solution is advantageous in forming a titanium dioxide nanostructure to be applied to a titanium precursor solution of 0.01 to 3 wt%.

The chemical treatment in the chemical treatment process may be performed for 1 minute to 4 hours at a chemical treatment temperature of 70 to 110 °C, and cracks do not occur in the subsequent heat treatment process, or the occurrence is insignificant, and the titanium dioxide substrate stably Layers can be formed. The chemical treatment in the chemical treatment process is performed for 1 minute to 4 hours at a chemical treatment temperature of 75 to 90°C. Even after going through the heat treatment process, a titanium dioxide base layer can be formed without cracking, and the efficiency of the reaction can be improved. It is better in that there is.

The heat treatment process is a process of preparing a titanium dioxide substrate including a titanium dioxide nanostructure on the surface of the base substrate using the chemically treated substrate.

Specifically, the heat treatment in the heat treatment process may be performed at 400 to 600° C. for 1 to 3 hours, and in this case, a nanostructure may be formed through an efficient process.

The titanium dioxide nanostructure thus formed may have any one structure selected from the group consisting of nanoparticles, nanoneedles, and combinations thereof.

The light-sensing wire including a titanium dioxide substrate layer including a titanium dioxide nanostructure on the base substrate thus prepared may be in the form of a wire having a predetermined diameter and length, and specifically, a wire having a diameter of about 1,000 μm or less. I can.

The light sensing wire may adjust the thickness of the light sensing outer ear by adjusting the thickness of the base material itself or by adjusting the thickness of the titanium dioxide base layer formed on the base material. Specifically, when a fine wire having a diameter of the base substrate of 1,000 μm or less and approximately the thickness of a human hair is applied, it is possible to manufacture an excellent light sensing wire with excellent sensitivity.

When the diameter of the base material is more than 500 μm and 1,000 μm or less, it is suitable for application as a light sensing wire that does not have a flexible characteristic, and can show a good photocharge response even under a low bias voltage condition. On the other hand, when the diameter of the base material is 1 μm to 500 μm, it can be applied as a flexible light sensing wire.

In addition, when the base material is flexible and has a diameter of 500 μm or less, the light sensing wire manufactured by the above method also maintains flexibility, that is, its flexible property, and thus it can be used as a fiber or non-planar material that requires a flexible base material. Its utilization is excellent.

In addition, when the basic substrate has flexibility and has a diameter of more than 500 μm and a light sensing wire is manufactured by the above manufacturing method, the flexibility may be lost after heat treatment, but the advantage of allowing light sensing even at a very low bias voltage. Can have Specifically, it is possible to provide an optical sensor capable of operating at a bias voltage of ± 1 to ± 7 and more excellently capable of driving even at a bias voltage of ± 3 V or less.

The light-sensing wire including a titanium dioxide base layer including a titanium dioxide nanostructure on the base base material thus prepared may be manufactured as an optical sensor according to a conventional method.

The optical sensor is positioned on the support substrate on the support layer (support substrate), and includes a wire-shaped basic substrate containing titanium and a titanium dioxide substrate layer including a titanium dioxide nanostructure grown on the basic substrate A light sensing wire; And a connection structure for connecting the light sensing wire to an external display device.

As the external display device, a display device such as a lamp or LED that displays the result of light sensing may be applied, but is not limited thereto, and the connection between the light sensing wire and the external display device is performed using a copper wire or silver solder. Conventional methods including can be applied. In addition, the support layer (supporting material) may be a PET film, for example, but is not limited thereto.

The light sensing device may react sensitively to light having a wavelength of 300 to 400 nm in which the light sensing wire reacts to ultraviolet rays and current flows. In particular, it has good sensitivity to specific light in the 340 to 380 nm wavelength range, and has excellent utilization as an optical sensor.

100 ㎛, 길이(L) ≤6 cm]의 Ti-wire 나노구조 재료를 COM(chemical oxidation-modification) 방법을 적용하여 완성하였다. 구체적으로, COM 방법을 적용하여, 플렉서블/논플렉서블 Ti-wire (Ø

800 ㎛, 100 ㎛)의 표면에는 균일하게 분산되며 연속적으로 반경방향으로 성장한 TiO₂ (아나타제 상) 나노니들/나노입자들을 형성시켰다.The present invention, non-planar human hair size (diameter (Ø))

A Ti-wire nanostructure material having a length of 100 μm and a length (L) ≤ 6 cm] was completed by applying a chemical oxidation-modification (COM) method. Specifically, by applying the COM method, flexible/non-flexible Ti-wire (Ø

800 µm, 100 µm) were uniformly dispersed on the surface and continuously grown in the radial direction to form TiO ₂ (anatase phase) nanoneedle/nanoparticles.

800 ㎛)는 직경이 약 100 ㎛인 광센서(Ø

100 ㎛)와 비교하여 더 우수한 광민감도를 보였다.The photoreactivity analysis results are 365 nm, 405 nm, at a bias voltage (±1 V or ±7 V) in which titanium dioxide nanostructures/titanium wire-based UV sensors (TiO2 NSs/Ti wire (TW) based UV sensors) are fixed. And a light source of various wavelengths of 535 nm was applied. Optical sensor with a diameter of about 800 ㎛ ( Ø

800 ㎛) is a light sensor with a diameter of about 100 ㎛ ( Ø

100 μm) showed better photosensitivity.

When the piezoelectric nanogenerator is connected in parallel with the optical sensor including the optical sensing wire described above, an optical sensor capable of driving without a separate battery can be manufactured.

As an example of the piezoelectric nanogenerator, a flexible wire based piezoelectric nanogenerator (FW-PNG), manufactured in a structure such as Ti/BTO NSs/PMMA/Pt, can be applied, and from mechanical defects For the purpose of protection, a polydimethylsiloxane (PDMS) packaging layer is formed on the FW-PNG and can be applied to experiments.

The FW-PNG is a flexible base material having the function of an internal electrode, and any one selected from the group consisting of nanoparticles, nanoneedles, and combinations thereof located on the flexible base material and on the surface of the flexible base material. A core-shell structure having a diameter of 1,000 μm or less as having flexibility, including a perovskite thin film layer containing titanium sambarium (Barium titanate, BaTiO ₃ ) including nanostructures; A support layer positioned on the core-shell structure; An external electrode layer on the support layer; And a packaging layer positioned on the external electrode layer, including a BTO-based flexible piezoelectric element.

In the present invention, a micro/nano device can be formed on a non-planar structure, and an energy recovery device of the size of a human maricarak can be provided, and a self-power sensor can be provided by combining them.

The method of manufacturing a titanium-based light sensing wire and the light sensing device of the present invention can be driven without a battery using a titanium-based light sensing wire that can be manufactured with the thickness of a human hair having a flexible or non-flexible characteristic using a modified chemical oxidation method. Yet, it is possible to provide an optical sensor that reacts sensitively to ultraviolet rays in a specific wavelength range under a low bias voltage. In addition, since in-situ radial growth of 360 degrees is possible, it can be applied to the device without a separate transfer process, so it is possible to manufacture a high-performance optical sensing wire and an optical sensor using it in a relatively simple and mild process. have.

800과 100 ㎛)를 위에서 관찰한 FE-SEM 사진(스케일바=100 ㎛, 확대된 삽입 사진의 스케일바=2 ㎛, 매끄러운 표현을 확인할 수 있음).
도 2는 본 발명의 실시예에서 합성한 Ti/TiO₂ NSs 코어-쉘 구조의 표면 모폴로지와 구조 분석 결과를 보여주는 사진. (a, c)는 Ø

800 ㎛인 티타늄 와이어 상에 성장한 TiO₂ NSs(나노니들과 나노파티클들)을 보여주는 FE-SEM 사진이고, (b, d)는 Ø

100 ㎛인 티타늄 와이어 상에 성장한 TiO₂ NSs(나노파티클)을 보여주는 FE-SEM 사진로, 삽입된 사진들은 외이어들 전체적으로 NSs가 연속적으로 방사상으로 잘 성장해 균일하게 분포되어 있음을 보여줌. (e)는 샘플들(Ti-wire, TiO₂ anatase powder, 티타늄 와이어 상에 TiO₂ NSs을 성장시킨 샘플, 각각 직경이 800 ㎛과 100 ㎛)의 라만 스펙트럼 측정 결과와, (f) Ti/TiO₂ NSs 코어-쉘 구조체(각각 직경이 800 ㎛과 100 ㎛인 티타늄 와이어 적용)의 광학사진과 100 ㎛ 티타늄와이어를 이용하여 제조한 샘플의 유연성 검증 사진.
도 3은 본 발명의 실시예에서 제조한 TW-UV 센서의 구조와 광반응 분석 결과를 보여주는 도면. (a)는 TW-UV 센서의 구조를 보여주는 개념도(삽입된 사진은 실시예에서 직경 800 ㎛의 티타늄 와이어를 이용하여 제조한 TW-UV 센서의 사진)이고, (b)는 365, 405 그리고 535 nm 파장의 다양한 광원에 따른 바이어스 전압 ±7 V의 고정 input의 기능을 보여주는 I-V response과 이에 적용된 TW-UV 센서의 사진(Ø

100 ㎛)을 보여주며, (c, d)는 TW-UV 센서(Ø

800 ㎛)의 I-V response을 보여주는 결과로 바이어스 전압은 ±1 V, 광원의 파장은 365, 405, 535 nm로 다양하게 적용한 것과, 과원의 파장을 365 nm로 적용하고 빛의 강도를 18, 36 및 60 mW/cm²로 다양하게 적용한 결과. (e, f)는 TW-UV 센서 (Ø

800 ㎛)의 I-T response analysis 결과로, 광원 파장은 365 nm, 빛의 강도는 각각

18 mW/cm², 40 및 60 mW/cm²로 적용한 결과.
도 4는 본 발명의 실시예에서 제조한 저온 열수 기술을 적용하여 플렉서블 티타늄 와이어(직경 100 ㎛) 상에 TiO₂ NSs을 BTO NSs로 변환시킨 과정을 설명하는 개념도(a), TiO₂ NSs/Ti wire, 혼합상의 BTO NSs/TiO₂ NSs/Ti-wire, 그리고 BTO NSs/Ti-wire 샘플들의 라만 스펙트럼(b), 제조한 Ti/BTO NSs core-shell wire와 사람 머리카락의 비교 사진(c), Ti/BTO NSs core-shell wire의 FE-SEM 사진(d, 스케일바 = 20 ㎛, 와이어 전체적으로 나노구조체가 균일하게 분포하며 연속적으로 반경방향 성장함), 나노로드와 나노입자가 램덤하게 성장한 모습을 보여주는 Ti/BTO NSs core-shell의 확대 사진(e, 스케일바 = 200 nm).
도 5는 본 발명의 실시예에서 제조한 Ti/TiO₂ NSs과 Ti/BTO NSs의 코어-쉘 플렉서블 와이어의 구성 원소 분석 결과인 XPS 스펙트럼을 보여주는 그래프(a), Ti 2p 원소(2p3/2, 2p1/2 스핀 상태)의 스캔 스팩트럼 결과(b), Ba 3d 원소(i.e. 3d5/2, 3d3/2 스핀 상태)의 스캔 스팩트럼 결과(c), O 1s 원소의 스핀 스펙트럼 결과(d).
도 6은 본 발명의 실시예에서 제조한 FW-PNG의 구조와 에너지 하베스팅 분석를 결과를 보여주는 도면. (a-c)는 기계적인 힘 2 N을 FW-PNG에 가한 후 측정한 I_SC, V_OC, 부하저항 분석(load resistance analysis) 및 순시면적전력밀도(instantaneous area power density)의 스위칭 극성 테스트 결과. (d)는 FW-PNG과 TW-UV 센서를 병렬 연결하여 제조한 BFW (또는 SP)-UV 센서의 모형을 서명하는 개념도. (e) 일정한 기계적 힘(2 N)과 365 nm 광원의 빛(빛의 세기 18, 40 및 60 mW/cm²)을 작용한 FW-PNG 및 BFW-UV 센서의 V_OC 측정 결과.
도 7은 본 발명의 실시예에서 제조한 티타늄 와이어(Ø

800) 상에 TiO₂ NSs이 성장한 샘플의 표면을 관찰한 FE-SEM 사진(스케일바, 100 ㎛). 위의 사진은 티타늄 와이어 상에 성장한 TiO₂ NSs의 두께를 확인하기 위하여 와이어의 끝 부분에서 촬영함.
도 8은 본 발명의 실시예에서 제조한 Ti-wire (800 ㎛) 상에 TiO₂ NSs가 성장한 모습을 관찰한 FE-SEM 사진.
도 9는 본 발명의 실시예에서 제조한 TW-UV 센서(Ø

100 ㎛)의 I-V response analysis 분삭 결과로, 다양한 빛의 세기(18, 36, 및 60 mW/cm²)로 파장 365 nm 의 조건으로 바이어스 전압 ± 7 V 의 기능을 살핀 결과.
도 10은 본 발명의 실시예에서 제조한 TW-UV sensor (Ø

100 ㎛)의 I-V response analysis 결과로, (a)는 다양한 빛의 세기(12.87, 25.74, 및 42.9 mW/cm²)로 파장 405 nm의 조건으로 바이어스 전압 ± 7 V 의 기능을 살핀 결과이고, (b)는 다양한 빛의 세기(12.27, 24.54, 및 40.9 mW/cm²)에서 파장 535 nm의 조건으로 바이어스 전압±8 V의 기능을 살핀 결과임.
도 11은 본 발명의 실시예에서 제조한 TW-UV sensor(Ø

800 ㎛)의 I-V response analysis를 보여주는 것으로, (a)는 다양한 빛의 세기(12.27, 24.54, 및 40.9 mW/cm²)로 파장 535 nm의 조건으로 바이어스 전압±1 V의 기능을 살핀 결과이고, (b)는 다양한 빛의 세기(12.87, 25.74, 및 42.9 mW/cm²)에서 파장 405 nm의 조건으로 바이어스 전압±1 V의 기능을 살핀 결과임.
도 12는 본 발명의 실시예에서 제조한 FW-PNG 장치의 개회로전압(a)과 단락전류(b)를 중지를 이용한 주기적인 생체역학적 힘을 이용하여 시험한 결과를 보여주는 그래프.1 is a diagram illustrating a process of radially growing TiO ₂ NSs on a titanium wire in an embodiment of the present invention (a: Comparative Example, b: Example). (a) The inserted pictures show the process of growing TiO ₂ NSs on a titanium wire with a diameter of 800 μm through chemical oxidation and direct heat treatment, and the heat treatment was performed at 500 °C and 700 °C for 2 hours, respectively. . In both cases, TiO ₂ NSs was not formed on the titanium wire, and it was observed that the wire recovered after heat treatment had a non-conductive property and a number of cracks were generated on the surface. (b) The inserted pictures show the process of growing TiO ₂ NSs on a titanium wire with a diameter of 800 μm through chemical oxidation and modified heat treatment, and the heat treatment was performed at 500 °C for 2 hours. In this case, TiO ₂ NSs were well formed on the titanium wire, and surface cracks did not occur. (c, d) is pure titanium wire ( Ø

800 and 100 μm) of the FE-SEM image observed above (scale bar = 100 μm, scale bar of the enlarged inset image = 2 μm, smooth expression can be confirmed).
2 is a photograph showing the surface morphology and structural analysis results of the Ti/TiO ₂ NSs core-shell structure synthesized in an example of the present invention. (a, c) is Ø

FE-SEM photograph showing TiO ₂ NSs (nanoneedle and nanoparticles) grown on 800 μm titanium wire, (b, d) is Ø

FE-SEM photograph showing TiO ₂ NSs (nanoparticles) grown on a 100 μm titanium wire. The inserted photographs show that NSs are continuously grown and distributed uniformly throughout the outer ears. (e) is a Raman spectrum measurement result of samples (Ti-wire, TiO ₂ anatase powder, TiO ₂ NSs grown on a titanium wire, respectively, diameters of 800 μm and 100 μm), and (f) Ti/TiO ₂ An optical photo of an NSs core-shell structure (with a titanium wire having a diameter of 800 µm and 100 µm, respectively) and a photo of verifying the flexibility of a sample manufactured using a 100 µm titanium wire.
Figure 3 is a view showing the structure of the TW-UV sensor manufactured in an embodiment of the present invention and photoreaction analysis results. (a) is A conceptual diagram showing the structure of the TW-UV sensor (the inserted photo is a photo of a TW-UV sensor manufactured using a titanium wire having a diameter of 800 μm in the embodiment), and (b) is a variety of wavelengths of 365, 405 and 535 nm. IV response showing the function of a fixed input with a bias voltage of ±7 V depending on the light source and a photo of the TW-UV sensor applied to it ( Ø

100 ㎛), and (c, d) is a TW-UV sensor ( Ø

800 ㎛) as a result of showing the IV response, the bias voltage is ±1 V, the wavelength of the light source is variously applied to 365, 405, 535 nm, and the wavelength of the orchard is applied to 365 nm, and the light intensity is 18, 36 The result of various applications at 60 mW/cm ² . (e, f) is the TW-UV sensor ( Ø

800 ㎛) of IT response analysis, the light source wavelength is 365 nm, the light intensity is

The result of applying 18 mW/cm ² , 40 and 60 mW/cm ² .
4 is a conceptual diagram illustrating a process of converting TiO ₂ NSs into BTO NSs on a flexible titanium wire (diameter 100 μm) by applying the low-temperature hot water technology prepared in the embodiment of the present invention (a), TiO ₂ NSs/Ti Raman spectra of wire, mixed BTO NSs/TiO ₂ NSs/Ti-wire, and BTO NSs/Ti-wire samples (b), a comparative picture of the prepared Ti/BTO NSs core-shell wire and human hair (c), FE-SEM photo of Ti/BTO NSs core-shell wire (d, scale bar = 20 ㎛, nanostructures are uniformly distributed throughout the wire and continuously grow radially), showing the random growth of nanorods and nanoparticles Enlarged photo of Ti/BTO NSs core-shell (e, scale bar = 200 nm).
5 is a graph (a) showing the XPS spectrum, which is a result of elemental analysis of the core-shell flexible wire of Ti/TiO ₂ NSs and Ti/BTO NSs prepared in an embodiment of the present invention, Ti 2p element (2p3/2, 2p1/2 spin state) scan spectrum result (b), Ba 3d element (ie 3d5/2, 3d3/2 spin state) scan spectrum result (c), and O 1s spin spectrum result (d).
6 is a view showing the results of the structure and energy harvesting analysis of the FW-PNG prepared in the embodiment of the present invention. (ac) is the switching polarity test result of I _SC , V _OC , load resistance analysis and instantaneous area power density measured after applying a mechanical force of 2 N to the FW-PNG. (d) is a conceptual diagram signing a model of a BFW (or SP)-UV sensor manufactured by connecting FW-PNG and TW-UV sensors in parallel. (e) V _OC measurement results of FW-PNG and BFW-UV sensors acting with constant mechanical force (2 N) and light of 365 nm light source (light intensities 18, 40 and 60 mW/cm ² ).
7 is a titanium wire manufactured in an embodiment of the present invention (Ø

800) FE-SEM photograph (scale bar, 100 μm) observing the surface of the sample on which TiO ₂ NSs were grown. The above picture was taken from the end of the wire to check the thickness of TiO ₂ NSs grown on the titanium wire.
Figure 8 is a FE-SEM photograph observing the state that TiO ₂ NSs grown on the Ti-wire (800 ㎛) prepared in the embodiment of the present invention.
9 is a TW-UV sensor manufactured in an embodiment of the present invention (Ø

100 μm) of the result of IV response analysis, the result of examining the function of bias voltage ± 7 V under conditions of wavelength 365 nm with various light intensities (18, 36, and 60 mW/cm ² ).
10 is a TW-UV sensor manufactured in an embodiment of the present invention (Ø

100 μm) of the IV response analysis result, (a) is the result of examining the function of bias voltage ± 7 V under the condition of wavelength 405 nm with various light intensities (12.87, 25.74, and 42.9 mW/cm ² ), ( b) is the result of examining the function of bias voltage ±8 V under the condition of wavelength 535 nm at various light intensities (12.27, 24.54, and 40.9 mW/cm ² ).
11 is a TW-UV sensor manufactured in an embodiment of the present invention (Ø

800 μm) of IV response analysis, (a) is the result of examining the function of bias voltage ±1 V under the condition of wavelength 535 nm with various light intensities (12.27, 24.54, and 40.9 mW/cm ² ), (b) is the result of examining the function of bias voltage ±1 V under the condition of wavelength 405 nm at various light intensities (12.87, 25.74, and 42.9 mW/cm ² ).
12 is a graph showing the results of testing the open circuit voltage (a) and short circuit current (b) of the FW-PNG device manufactured in the embodiment of the present invention using periodic biomechanical force using a stop.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

Experiment method

TiO on flexible titanium wire ₂ Radial growth of the back:

The following two methods were applied on the flexible titanium wire. The first step is to grow TiO ₂ NSs on the surface of the titanium wire using the COM method, and the _second step is to convert TiO ₂ NSs to BTO NSs through a low temperature hydrothermal process.

100 ㎛]는 탈이온수로 10분 동안 세척한 후 공기건조 시켰다. 이후, 1차처리된 티타늄와이어는 20 wt% 과산화수소 용액(hydrogen peroxide, H₂O₂, Junsei Chemical Co. Ltd, Japan)에 담구어 밀폐된 용기에 보관하고 80 °C에서 24 hr(시간) 동안 2차처리를 진행했다. 이후, 탈이용수를 이용하여 2차처리된 티타늄와이어를 세척하고 공기건조 시켜 전처리된 티타늄와이어를 준비했다.(Pre-treatment) The flexible titanium wire substrate was purchased and used, each having a diameter of 100 μm and 800 μm (The Nilaco Corporation, Japan). Titanium wires were taken in various lengths and immersed in 5 wt% oxalic acid solution (oxalic acid, Kanto Chemical Co. Ltd, Japan) at 100 °C for 2 hours to perform primary treatment. Treated Titanium Wire[(Ø)

100 μm] was washed with deionized water for 10 minutes and air-dried. Thereafter, the primary treated titanium wire was immersed in a 20 wt% hydrogen peroxide solution (hydrogen peroxide, H ₂ O ₂ , Junsei Chemical Co. Ltd, Japan), stored in a sealed container, and stored at 80 °C for 24 hr (hours). The secondary treatment was carried out. Thereafter, the secondary treated titanium wire was washed with deionized water and air-dried to prepare a pretreated titanium wire.

(Growth of TiO ₂ NSs) Pretreated titanium wires were added to a 0.2 wt% TiCl ₃ solution [titanium (III) chloride, Kanto Chemical Co. Ltd, Japan] and then chemically treated at 80 °C for 2 hr (hour). The treated titanium wire was washed with deionized water for 10 minutes and then air dried. after. A flexible core-shell wire (Ti/TiO ₂ NSs structure) by placing the chemically treated titanium wire in a long aluminum boat and performing heat treatment for 2 hours in an air atmosphere at 500 °C using an open tubular furnace. Got it.

100 ㎛)를 탈이온수로 수차례 세척하여 불순물을 제거하였고 대기건조 시켰다.(Growth of BTO NSs) Hydrothermal synthesis was applied to the growth of BTO NSs. 0.1 M Ba(OH) ₂ .8H ₂ O solution (barium hydroxide octahydrate, Daejung Chemicals, Korea) and 0.6 M KOH solution (potassium hydroxide, Daejung Chemicals, Korea) were prepared as a hydrothermal solution. 50 ml of the prepared hydrothermal solution was poured into a Teflon bowl, and TiO ₂ NSs/Ti flexible wire was completely immersed in the solution. After filling the Teflon bowl with the solution, it was tightly sealed and hydrothermal reaction was performed at 180 °C for 24 hours using an autoclave. After the hydrothermal reaction is completed, the flexible BTO NSs/Ti wire (Ø

100 μm) was washed several times with deionized water to remove impurities and air dried.

TiO ₂ /Ti wire-based optical sensor (TW-UV sensor) device manufacturing

1 cm)와 다양한 직경(Ø

800 ㎛, 100 ㎛)을 갖는 TiO₂ NSs/Ti 와이어를 PET(polyethylene terephthalate) 기재에 성장시켜 적용하였다. 성장된 TiO₂ NSs/Ti 와이어는 PET 기재 상에 위치시키고, 양 끝을 은(Ag paste)으로 접착한 후 70 °C 이상의 온도에서 30분 동안 열처리를 진행하였다. 이후, 건조된 은은 에폭시 폴리머와 함께 분리되었고, 외부 노이즈/단락 전류 파라미터를 조절할 수 있도록 하였다. TW-UV 센서의 외부 연결은 플렉서블 구리 와이어를 적용했고, 상부 표면을 유연성 캡톤 테이프로 덮어 마무리했다.TW-UV sensor (TiO ₂ /Ti wire based UV-sensor) has a certain length (

1 cm) and various diameters (Ø

800 μm, 100 μm) TiO ₂ NSs/Ti wire was grown on a PET (polyethylene terephthalate) substrate and applied. The grown TiO ₂ NSs/Ti wire was placed on a PET substrate, and both ends were bonded with silver (Ag paste), and then heat treated at a temperature of 70 °C or higher for 30 minutes. Thereafter, the dried silver was separated together with the epoxy polymer, and the external noise/short-circuit current parameter could be adjusted. The external connection of the TW-UV sensor is made of flexible copper wire, and the upper surface is covered with flexible Kapton tape.

4 cm, Ø

100 ㎛)은 저온 수열 과정으로 제조되었고, PMMA/PDMS 코팅층들은 딥코팅법으로 형성했다. PMMA/BTONSs/Ti 와이어 상에 형성되는 외부 은 전극층은 브러쉬 코팅 기술로 제조되었다.FW-PNG (Flexible wire based BTO piezoelectric nanogenerator) was fabricated in five layers. Active piezoelectric layer (BTO NSs), two electrodes (internal electrode: titanium electrode, external electrode: silver electrode), and two insulating layers, PMMA (polymethyl methacrylate, mechanical stability reinforcement) and PDMS (polydimethylsiloxane, packaging layer). The layers are organized. BTO NSs (L

4 cm, Ø

100 μm) was prepared by a low-temperature hydrothermal process, and the PMMA/PDMS coating layers were formed by a dip coating method. The outer silver electrode layer formed on the PMMA/BTONSs/Ti wire was manufactured by brush coating technology.

How to measure:

514 nm과 input power 15 mW 조건에서 측정하였다.The phase of the TiO ₂ NSs and BTO NSs on the flexible titanium wire was sourced using a Raman spectroscopic instrument (LabRAM HR Evolution; Horiba, Japan).

It was measured under the conditions of 514 nm and 15 mW of input power.

The elemental composition and oxidation number of the surface of the flexible titanium wire were measured using an X-ray photoelectron spectrometer. The growth surface of the flexible titanium wire was analyzed using a field emission scanning electron microscopy (FE SEM, Model: Zeiss Supra-55vp).

The open circuit voltage and short circuit current were measured using 6514 electrometer (Keithley) and 6584 picoammeter (Keithley), respectively.

1 m/s²의 가속으로 전진 또는 후진하는 시스템이다. FW-PNG에 적용된 입력 생체역학적 에너지는 인간 검지손가락의 주기적인 움직임을 이용하였다. TW-UV 센서의 I-V 및 I-T 그래프 특성은 고정 바이어스 전압 하에서 다양한 파장을 갖는 광원(Prizmatix Ltd., 365, 405 및 535 nm)을 이용하여 측정되었고, 측정은 반도체 특성분석기(Agilent-B1500A)를 이용하여 측정되었다.With cyclic mechanical force (2 N), a linear motor system (LinMot-HF01-37) was used, and a shaft mass of 2 Kg was

It is a system that moves forward or backward with an acceleration of 1 m/s ² . The input biomechanical energy applied to the FW-PNG used the periodic movement of the human index finger. The IV and IT graph characteristics of the TW-UV sensor were measured using a light source having various wavelengths (Prizmatix Ltd., 365, 405 and 535 nm) under a fixed bias voltage, and the measurement was performed using a semiconductor characteristic analyzer (Agilent-B1500A). Was measured.

Experiment result

After applying the COM method on the titanium wire, TiO ₂ nanoneedles and nanoparticles in the form of anatase crystals arranged radially were grown by immersing for 2 h (hour) at 500 °C. Conditions for the growth process of TiO ₂ NSs are the same as described in the above experimental method, and this process will be described in more detail with reference to FIG. 1 schematically.

First, in a sealed container, the outer surface of the titanium wire was treated with a 5 wt% oxalic acid solution (immersed for 2 h at 100 °C) and a 20 wt% H ₂ O ₂ solution (immersed at 80 °C for 24 h). In this case, the application of an aqueous oxalic acid solution may improve adhesion/coating properties by etching the outer surface of the titanium wire. During this treatment, the outer surface of the titanium wire can be changed to titanium oxalate, and the excess oxalic acid solution after sufficient reaction has been induced can be removed by a simple method of washing with deionized water and drying in an air atmosphere. have. It is believed that this type of treatment is easier, more efficient and less costly than treatment with hydrochloric acid.

Next, the H ₂ O ₂ solution treatment of the titanium wire may change the shape of the surface and increase the thickness of the oxide layer. By controlling the immersion time and the concentration of the H ₂ O ₂ solution, the surface roughness of the titanium surface can be adjusted from the nanometer level (1 to 6 h, 30 wt %) to the micrometer level (≥ 24 h, 30 wt %). In this study, the surface of a titanium wire pretreated with an oxalic acid solution was treated with a 20 wt% H ₂ O ₂ solution for 24 hours to obtain a surface roughness of 1 μm or more.

Two methods were applied to change the outer surface of the titanium wire to TiO ₂ .

The first method is a direct heat treatment method, in which a flexible titanium wire treated with oxalic acid and hydrogen peroxide is subjected to heat treatment at different temperature conditions in an air atmosphere. The conductive flexible titanium wire was changed to non-conductive by heat treatment conducted for 2 hours at 500 °C and 700 °C, respectively. Loss of conductivity and flexibility, and a state in which the color of the titanium wire changed from glossy gray to milky white can be seen in FIG. 1A. The Raman analysis pattern did not show the TiO ₂ anatase phase in the samples subjected to direct heat treatment above. The second method is to immerse the chemically treated TiO ₂ wire in a TiCl ₃ solution at 80 °C for 2 h (hours), and then place the wire in an open tube furnace for 2 h (hours) in an air atmosphere at 500 °C. During heat treatment (see FIG. 1 b).

800 μm, 100 ㎛)을 갖는 전도성 티타늄 와이어의 표면 모폴로지를 보여준다(스케일바 100 ㎛, 삽입된 사진은 순수한 티타늄 와이어를 위에서 관찰한 매끈한 표면 모폴로지를 보여주는 사진, 스케일바 2 ㎛). 여기서 나노입자의 성장과 관련된 형태는 관찰되지 않았다.1 c and d are different diameters (Ø

800 μm, 100 μm) shows the surface morphology of the conductive titanium wire (scale bar 100 μm, inset photo shows the smooth surface morphology observed from above, scale bar 2 μm). Here, no morphology related to the growth of nanoparticles was observed.

On the other hand, the outer surface of the chemically modified titanium wire was observed in Figure 2 a to d. The external surface of the chemically changed titanium wire showed the continuous growth of nanostructures forming a forest. 2A shows the surface morphology of TiO ₂ NSs/Ti-wire (Ø = 800 µm) (scale bar 100 µm), and referring to the enlarged inset image and Fig. 3, the thickness is about 1 to 5 µm TiO _It was confirmed that ₂ was uniformly grown.

Two distinct types of TiO ₂ NSs, nanoneedles and nanoparticles, were grown on the surface of a titanium wire (Ø = 800 µm), and FE-SEM images showed that the nanoneedles grew through the outer surface of the titanium wire, the bottom layer. Note, it was confirmed that the nanoparticles were distributed like small islands at each location (see Fig. 2c and Fig. 8a to d). The particle size of the nanoparticles was variously observed from 50 nm to 200 nm (see b of FIG. 8), the length of the nanoneedle was observed with various lengths within a few micrometers, and the diameter (Ø) was as shown in FIG. Likewise, it was observed below 20 nm. The TiO ₂ nanoneedle is in direct contact with the outer surface of the titanium wire as shown in FIG. 8 c and d, and as shown in FIG. 2 b, the TiO ₂ growth pattern is also directly uniform on the titanium wire (Ø = 100 µm). It was observed to have grown significantly. Interestingly, it was observed that only nanoparticles were grown on the surface of the titanium wire of Ø = 100 µm (see d of FIG. 2).

Crystal morphology and dynamic symmetry of nanostructures (NSs) grown using Raman spectroscopy (λexe =514 nm, power =20 mW) were observed.

Figure 2e is a Raman pattern of a commercially obtained titanium wire (Nilaco corporation), TiO ₂ powder (Daejung chemical Pvt. Ltd), and a chemically treated titanium wire having a diameter (Ø) of 100 μm and 800 μm, respectively. This is a comparison graph.

No active Raman mode was observed for the conductive pure titanium wire. On the other hand, in the commercially obtained TiO ₂ crystalline powder, active forms at 147, 200, 400, 519 and 642 cm ^-1 corresponding to the anatase phase structure of TiO ₂ nanoparticles were observed.

Changes in full width at half maximum (FWHM), strength, and peak position may vary depending on the size of NSs, phonon confinement behavior, anatase-rutile mixed phase, and non-stoichiometric properties of TiO ₂ .

In addition, in the chemically modified titanium wire (diameter 800 µm), a Raman active type was observed in the wavelength range of 100 cm ^-1 to 750 cm ^-1 , and the main peaks were observed at 143, 397, 514 and 633 cm ^-1 , respectively. .

In the E _g mode, the main peak located at 143 cm ^-1 showed strong intensity compared to other peaks, which is interpreted as external vibration of the anatase structure formed in a long range of anatase-type TiO ₂ . Other peaks such as 397, 514 and 633 cm ^-1 appeared in various modes such as B _1g , A _1g + B _1g and E _g , indicating that TiO ₂ NSs grew well on the titanium wire (e in FIG. 2 Reference). All these peaks appeared very similar in each sample and matched the Raman pattern of commercially available anatase-type TiO ₂ nanopowder well.

The small secondary peak observed at 433 cm ^-1 along the peak of 397 cm ^{-1 indicates} the presence of a weak rutile phase. Similarly, the Raman pattern of the chemically modified titanium wire having a diameter of 100 μm shows a similar peak behavior of the TiO ₂ anatase phase structure as shown in e of FIG. 2.

≤3 cm^-1, 상업적으로 입수가능한 아나타제 상의 TiO₂ 나노파우더의 라만 패턴과 비교), 이는 성장한 나노입자들의 크기와 이의 형태에 의한 변화라 생각된다.However, some peaks, such as 517 and 611 cm ^-1 , showed low change in wavelength, and some wavelengths such as 145 and 402 cm ^-1 showed high change in wavelength (

≤3 cm ^-1 , compared to the Raman pattern of commercially available TiO ₂ nanopowder on anatase), which is believed to be a change due to the size and shape of the grown nanoparticles.

2F is a photograph of Ti/TiO ₂ NSs based on a titanium wire having a diameter (Ø) of about 800 μm and about 100 μm, respectively. Titanium wire with a diameter of 800 µm has shown that TiO ₂ nanostructures (nanoneedle and nanoparticles) can grow radially in the 360° direction in a range of several centimeters having a length of 1.5 to 5.5 cm, but titanium wire It showed the disadvantage of losing the flexibility. This means that the Ti/TiO ₂ core-shell wire having a diameter of 800 μm is not suitable for application to a smart flexible device such as a flexible harvester or a sensor, but is useful for a device that does not require flexible characteristics such as an optical sensor.

A titanium outer ear with a diameter (Ø) of 100 μm showed radial growth of TiO ₂ similar to that of 800 μm in diameter. However, as shown in b and d of FIG. 2, one surface morphology was shown like the TiO ₂ nanoparticles, and it was also confirmed that it has excellent flexibility as shown in f of FIG. 2.

800 ㎛)의 광학 사진을 보여준다.An implementation of the device structure of Ag to the PET sheet, - since, NSs TiO2 formed on a titanium wire (800 μm, 100 ㎛) is TW-UV- sensor (e.g., a metal:: Ag- semiconductor metal TiO ₂ 3A). The inserted photo shows the manufactured non-flexible TW-UV sensor ( Ø

800 μm) of the optical picture.

100 ㎛)도 제조되었다(삽입 사진은 제조된 샘플의 광학사진). 또한, 암소에서 다양한 파장(365 nm, 405 nm 및 535 nm)과 세기의 광원을 적용하여 전기적 특성을 측정하여, 도 3의 b에 나타냈다. 유연성 TW-UV 센서를 암소에 위치시키고, ±7 V의 바이어스 전압 조건에서 I-V response를 관찰한 결과 비저항 거동(non-ohmic behavior)을 보였다. 이는, TiO2 NSs(atomic level TiO2 regulated surface: 4.13 eV)과 Ag (4.26 eV)금속의 사이의 접촉이 형성되었고, NSs의 반경방향 성장에 의존하였다는 것에서 기인하는 것으로 생각된다. 유연성 TW-UV 센서는, 405 nm(maximum power

42 mW/cm²)과 535nm(maximum power

40 mW/cm²)와 같은 파장의 광원 하에서 전류 반응(-7 V에서 25 nA)에 변화를 보이지 않았다. 그러나, 365 nm(maximum power

60 mW/cm²)의 경우에는 약 4배 강도로 상당한 전류 반응의 변화가 관찰되었다(도 3b 참고).In a similar process, the flexible TW-UV sensor ( Ø

100 μm) was also prepared (inset photo is an optical photo of the prepared sample). In addition, electrical characteristics were measured by applying light sources of various wavelengths (365 nm, 405 nm and 535 nm) and intensity in a dark place, and are shown in b of FIG. 3. The flexible TW-UV sensor was placed in a dark place, and the IV response was observed under the condition of ±7 V bias voltage, showing a non-ohmic behavior. This is thought to be due to the fact that the contact between the TiO2 NSs (atomic level TiO2 regulated surface: 4.13 eV) and the Ag (4.26 eV) metal was formed and depended on the radial growth of the NSs. Flexible TW-UV sensor, 405 nm (maximum power

42 mW/cm ² ) and 535nm(maximum power

There was no change in the current response (25 nA at -7 V) under a light source of the same wavelength as 40 mW/cm ² ). However, 365 nm (maximum power

In the case of 60 mW/cm ² ), a significant change in current response was observed with an intensity of about 4 times (see FIG. 3B).

3C is a result of measuring the IV response of the non-flexible TW-UV sensor in the dark or under various light sources and a bias voltage of ±1 V. Non-flexible TW-UV sensor but a similar reaction and flexible TW-UV sensor, I _D (dark current) and showed a difference in terms of I _Ph (photocurrent) at 365 nm conditions, low operating bias voltages (± 1 V) There was also a difference. In particular, the non-flexible I _D of the TW-UV sensor I _D of the flexible TW-UV sensor Was observed to be larger than that. Since the lengths between the two silver electrodes were the same in both samples, the increased current response was thought to be due to the synergistic effect of the nanoneedle and nanoparticle structures grown by bonding on the non-flexible titanium wire. It may also be due to the thickness of the radial growth of the nanostructures.

I _Ph of non-flexible TW-UV sensor due to the light intensity of 365 nm wavelength light source The response is depicted in Figure 3D. I _Ph The change of was observed while the light intensity was changed from 0 mW to 18 mW/cm ² (365 nm source), and as the intensity increased at 18 mW/cm ² to 36 mW/cm ² and 60 mW/cm ² It increased proportionally (see FIG. 3D).

Similar I _{Ph for} flexible TW-UV sensors A reaction was observed and is shown in FIG. 9. In addition, light intensity function evaluation ( P _L ) was performed at wavelengths of 405 nm and 535 nm using the same equipment, and are shown in FIGS. 10 and 11. I _D The and I _Ph results show that there is no change in the UV sensors manufactured in light sources with wavelengths of 405 and 535 nm, respectively.

These results clearly show that TiO2 NSs grown on flexible/non-flexible titanium wires have good sensitivity in the light intensity of 365 nm wavelength light source.

In this experiment, the length of the TW-UV sensor and the titanium core were the same, but the non-flexible TW-UV sensor (when both nanoneedle and nanoparticle were grown) showed high sensitivity at low operating bias voltage (≤ 1 V). Was shown, and the flexible TW-UV sensor (when nanoparticles were grown) was operated at ≥ 1 V.

This difference clearly shows that the operating voltage or bias voltage is dependent on the type of NSs grown and its thickness.

-1 V에서 논플렉서블 TW-UV 센서의 I_Ph/I_D ratio는 2.19이고, 두 장치의 활성면적(S)의 면에서 R _λ (photo-responsivity)는 아래의 식 1로 평가될 수 있다.Bias voltage

At -1 V, the I _Ph /I _D ratio of the non-flexible TW-UV sensor is 2.19, and R _λ (photo-responsivity) in terms of the active area (S) of the two devices can be evaluated by Equation 1 below.

(Equation 1)

800 ㎛)의 bias voltage

-1 V 에서의 광민감도(photo-responsivity)는 35.024 μA/W이었고, 이는 플렉서블 TW-UV 센서(Ø

100 ㎛)에서의 bias voltage

-1 V 에서의 광민감도(1.682 μA/W) 보다 높은 값이다.Calculated non-flexible TW-UV sensor ( Ø

800 ㎛) bias voltage

The photo-responsivity at -1 V was 35.024 μA/W, which is a flexible TW-UV sensor ( Ø

100 μm) bias voltage

It is higher than the light sensitivity at -1 V (1.682 μA/W).

I _D 로부터 최고 I _Ph 의 63%에 이르는데 필요한 시간)과, 회복 시간(recovery time 또는 fall time, Tf

최고 I _Ph 의 37% 회복에 필요한 시간)은 각각

13.9 초와 10.23 초로 나타났다(도 3의 e참고)When a 365 nm light source is applied at 18 mW/cm ² , the response time of the non-flexible TW-UV sensor (response time or raise time, Tr

The time required to reach 63% of the maximum I _Ph from I _D ) and the recovery time (recovery time or fall time, Tf

The time required to recover 37% of the highest I _Ph ) is each

It appeared at 13.9 seconds and 10.23 seconds (see e in Fig. 3).

First, the dark current observed at the bias voltage of 1 V starts to increase when light is applied to the device, and takes more than 60 S (seconds) until it reaches the maximum value. The current due to light starts to decrease regardless of whether the input incident light intensity is OFF, and at the same time, the device reaches a dark current value (see e of FIG. 3).

3F is a result of observing the IT response of the non-flexible TW-UV sensor at about 365 nm wavelength light source at various light intensities (18, 36 and 60 mW/cm ² ), and current proportional to the light intensity Show behavior.

Conversion of TiO ₂ nanoparticles into BTO NSs was performed using a flexible wire having a diameter of about 100 μm, and a flexible wire-based energy harvesting device for conversion of biomechanical energy and X-ray photoelectron spectroscopy was performed. As described in the conceptual diagram in FIG. 4A, the process of converting TiO ₂ nanoparticles on the titanium wire into BTO nanostructures is a method of performing a hydrothermal process for 24 hr (hour) by applying a process temperature of 180 °C. Proceeded. After finishing the chemical pretreatment process, the flexible wire was washed several times with deionized water and air dried to prepare it. As shown in b of FIG. 4, it was confirmed whether the nanostructure formed on the flexible titanium wire by Raman spectrum was BTO NSs. The Raman pattern indicated in black is the result of measuring the hydrothermal treated sample (0.1 M Ba(OH) ₂ .8H ₂ O: flexible wire treated with 0.1 M KOH solution), showing various active vibration modes, and showing various active vibration modes, and showing anatase TiO ₂ It shows that nanoparticles and BTO nanostructures are mixed. Broad peaks at 147, 438, and 607 cm ^-1 are associated with TiO ₂ nanoparticles, and peaks at 248 cm ^-1 and 311.94 cm ^-1 are associated with BTO NSs formation. These results show that the hydrothermal reaction does not proceed sufficiently at low concentrations of KOH.

The red Raman pattern shown in b of FIG. 4, which is the result of the sample treated with the flexible TiO ₂ NSs/Ti wire, was treated with a Ba(OH) ₂ .8H ₂ O solution (0.1 M) and a high concentration KOH solution (0.6 M). It shows these characteristics. This pattern shows that the main peak of the anatase TiO ₂ completely disappeared and new peaks were created at various locations such as 186, 304, 511 and 724 cm ^-1 , which confirmed that TiO ₂ was completely converted into BTO nanostructures. It is the result.

17 내지 181 ㎛]의 비교 사진을 보여준다.304 cm ^-1 position applied in [B ₁ (TO+LO), E] mode and 511 cm ^-1 peak applied in [A ₁ (TO), E] mode, and 186 cm ^-1 [A ₁ (TO ), E (LO)], 724 cm ^- 1 [A ₁ (TO), E (LO)] The characteristic of the main peak including other peaks is that the radially grown BTO NSs are in the tetragonal crystalline phase. Show that it is. The peak at 155 cm ^-1 is thought to be due to an internal defect in the BTO crystal lattice. Here, the concentration of KOH is thought to be a key variable when converting TiO ₂ nanoparticles into BTO nanostructures. 4C shows the prepared Ti/BTO NSs core-shell wire [Ø ≤ 100 µm, length (L) several centimeters or less] and human hair [Ø

17 to 181 μm] are shown in comparative pictures.

4 d and e are FE-SEM photographs of Ti/BTO NSs core-shell wire (d, scale bar = 20 µm, nanostructures are uniformly distributed throughout the wire and continuously grow radially), nanorods and nanoparticles An enlarged FE-SEM image (e, scale bar = 200 nm) of the Ti/BTO NSs core-shell showing the random growth is shown. As for the surface morphology observed in the photograph, it was confirmed that BTO NSs grew well in the radial direction in two forms, nanorods and nanoparticles on the outer surface of the titanium wire, and were uniformly dispersed. The diameter of the nanorods was 350 nm or less, the length was several centimeters, and the size of the nanoparticles was observed to be 200 nm or less (see e of FIG. 4).

X-ray photoelectron spectroscopy (XPS) technology was applied to confirm the elemental composition and chemical state of the nanostructures grown on the flexible titanium wire. In FIG. 5A, black is a graph showing the XPS spectrum of a core-shell flexible wire in which TiO ₂ NSs is formed on a Ti wire, and shows the presence of Ti, O, and C elements. In addition, as shown in b of FIG. 5, binding energies of 464 eV and 458.5 eV by Ti 2p1/2 and Ti 2p3/2 are observed. The two peaks show a difference in binding energy of about 6 eV, which seems to be due to Ti having an oxidation number of 4+. As shown in d of FIG. 5, in the TiO ₂ lattice structure, a binding energy peak of 529.5 eV corresponding to O 1s was observed.

Similarly, the red graph in Fig. 5A showing the XPS spectrum of the core-shell flexible wire of BTO NSs grown on the Ti wire shows the presence of Ba, Ti, O and C elements on the titanium wire surface. The strongest peak of 780 eV binding energy corresponds to Ba 3d _5/2, and the peak at 797 eV corresponds to Ba 3d _3/2 (see c of FIG. 5). These two peaks are due to the fact that the oxidation number of mode Ba is ²⁺ . The positions of the Ti 2p and O 1s oxidation peaks were slightly shifted, and no change was observed in the width of the peak indicating the internal stress of the TiO ₆ octahedron in the BTO lattice structure (see b and d of FIG. 5). The peaks at 88 eV and 176 eV binding energies representing the Ba 4d and Ba 4p spin states indicate that other barium orbitals may exist in the BTO crystal pool.

The piezoelectric effect of BTO NSs grown on a flexible titanium wire by manufacturing a flexible wire-based piezoelectric nanoelectric power device (FW-PNG) was analyzed (see FIG. 6D ). The length of the FW-PNG device was about 4 cm, and the thickness of the 5≦nanostructure was≦10 μm.

FW-PNG consists of a total of 5 layers, the piezoelectric active layer as BTO NSs, the support layer as PMMA, the inner electrode as the conductive titanium wire, the outer electrode as the silver (Ag) layer, and the packaging layer as the PDMS as mentioned above. to be.

6A and 6B show I _SC and V _OC of the FW-PNG device to which a periodic load (about 2 N) is applied. The measured pp I _SC and V _OC values were about 600 nA and about 7 V (total device area: 1.2568 mm ² ). A switching polarity test was performed to check whether the generated current was due to the FW-PNG device, and the results are shown in FIG. 6A. In the forward connection, the FW-PNG device showed a positive peak whenever a mechanical load was applied, and a negative peak after the load was removed. In reverse connection, the FW-PNG device showed a negative peak when a mechanical load was applied, and a positive peak after the load was removed. This means that the FW-PNG device showed a clear phase shift on the output signals in the forward and reverse connection, and that the output value appeared due to mechanical load application without any other external factors. The results of load resistance analysis and P _A (instantaneous area power density) of FW-PNG according to mechanical load (about 2 N) are shown in FIG. 6C. The generated output voltage increased in proportion to the increase of the load resistance, and the maximum P _A of the obtained FW-PNG was 22.5 ㎼/cm ² at 10 MΩ (Fig. 6 c). This is a result clearly showing that the optimal load resistance of FW-PNG is 10 MΩ.

For real-time analysis, a BFW-UV sensor (battery-free wire based UV sensor) was prepared as shown in FIG. 6D by combining the prepared FW-PNG and TW-UV sensor. In this case, the FW-PNG devices are connected in parallel and operate as a sustainable accident-independent power source that drives the highly functional TW-UV sensor.

7 V가 생산되었는데, 이 전압값이 NG의 출력단이 TW-UV 센서의 입력단과 연결되어 있을 때 동일한 부하조건에서 약 2 V 까지 감소되었다. 출력전압의 감소는 FW-PNG 장치(최대 전력밀도를 위한 부하 매칭 저항: 약 10 MΩ)와 TW-UV 센서(I-V 그래프로부터 계산된 저항 범위는 약 600 내지 800 kΩ)의 저항 미스매치에 의한 것이다. 또한, 18 mW/cm², 40 mW/cm² 및 60 mW/cm² 의 다양한 광 강도의 UV source (365 nm)를 TW-UV 센서에 적용하였을 때, 피크-피크 전압 출력이 도 6의 e에 보인 바와 같이 460 mV, 330 mV 과 90 mV로 줄어들었다.First of all, the FW-PNG device is pp V _OC when load 2 N is applied.

7 V was produced, and this voltage value was reduced to about 2 V under the same load condition when the output terminal of NG was connected to the input terminal of the TW-UV sensor. The decrease in output voltage is due to a mismatch of resistance of the FW-PNG device (load matching resistance for maximum power density: about 10 MΩ) and the TW-UV sensor (the resistance range calculated from the IV graph is about 600 to 800 kΩ). . In addition, when a UV source (365 nm) of various light intensities of 18 mW/cm ² , 40 mW/cm ² and 60 mW/cm ² is applied to the TW-UV sensor, the peak-peak voltage output is e of FIG. 6 As shown in the figure, it was reduced to 460 mV, 330 mV and 90 mV.

The piezoelectric effect of the FW-PNG device was evaluated by the piezoelectric force and piezoelectric current in response to the force of the index finger, which is a biomechanical force. 12A and 12B show that pp V _OC and I _SC of FW-PNG were 3V and 120 nA, respectively. It is thought that the asymmetric characteristics on the graph are due to the asymmetric characteristics of the finger force. These results show that biomechanical energy is successfully converted into electrical energy by the direct piezoelectric effect of BTO NSs on titanium wire.

In this experiment, it was confirmed that a single FW-PNG device with a small area can produce significant output electricity (power density: about 22.5 ㎼/cm ² , 2 N load condition). It is thought that a considerable output energy can be produced by implementing the flexible BTO NSs/Ti wire stack or combination.

These results are that the radially grown TiO2 NSs (nanoneedles, nanoparticles)-based wire can be applied to optoelectronic devices, and the mechanical energy (e.g., movement of the human body, mechanical vibration, etc.) is discarded by the BTO nanoparticle-based flexible outer ear. It clearly shows that it is suitable for collecting ).

This kind of low-dimensional semiconductor/piezoelectric element wire based on in-situ radial growth is a smart wire used in devices such as sustainable power sources, solar cells, memristors, and portable/flexible self-charging sensors. As a method of producing, the utilization is great.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It belongs to the scope of rights of

Claims (11)

A primary treatment step of treating a base base material containing titanium with an acid solution to prepare a primary treatment base material having an etched outer surface thereof;
A secondary treatment step of oxidizing the primary treatment base material to prepare a secondary treatment base material having a controlled surface roughness;
A chemical treatment process of preparing a chemically treated chemical treatment substrate by immersing the secondary treatment substrate in a titanium precursor solution; And
A heat treatment process of heat-treating the chemically treated substrate to prepare a light sensing wire including a titanium dioxide substrate layer including a titanium dioxide nanostructure on the base substrate. The method of claim 1,
The acid solutions applied in the first treatment process are lactic acid, citric acid, malic acid, oxalic acid, acetic acid, tartaric acid, and Dipic acid, succinic acid, maleic acid, glutamic aicd, fumaric aicd, pyruvic aicd, gluconic acid, satric acid ctric acid), aspartic acid, and terebic acid, which is a weak acid solution selected from the group consisting of, a method of manufacturing a light sensing wire. The method of claim 2,
The weak acid solution is a weak acid aqueous solution of 1 to 10% by weight, a method of manufacturing a light sensing wire. The method of claim 1,
Chemical treatment in the chemical treatment process is to proceed at a chemical treatment temperature of 70 to 110 ℃, the manufacturing method of the light sensing wire. The method of claim 1,
The oxidation of the secondary treatment process is performed by immersing the primary treatment substrate in a hydrogen peroxide solution. The method of claim 1,
The heat treatment in the heat treatment process is performed at 400 to 600° C., a method of manufacturing a light sensing wire. The method of claim 1,
The base material is in the form of a wire having a diameter of 1 μm to 1,000 μm, the method of manufacturing a light sensing wire. Supporting substrate;
A light sensing wire positioned on the support substrate and including a titanium dioxide substrate layer including a wire-shaped basic substrate containing titanium and a titanium dioxide nanostructure grown on the basic substrate; And
Containing, a light sensing device with a connection structure for connecting the light sensing wire to an external display device. The method of claim 8,
The light sensing device is in response to ultraviolet rays. The method of claim 8,
The base material is flexible, and the diameter is 1 μm to 500 μm, and the light sensing wire is flexible. The method of claim 8,
The base material is a diameter of more than 500 μm to 1,000 μm or less, and the light sensing wire operates at a bias voltage of ± 3 V or less.

Images