WO2017213581A1 - Matériau nanostructuré - Google Patents

Matériau nanostructuré Download PDF

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Publication number
WO2017213581A1
WO2017213581A1 PCT/SE2017/050620 SE2017050620W WO2017213581A1 WO 2017213581 A1 WO2017213581 A1 WO 2017213581A1 SE 2017050620 W SE2017050620 W SE 2017050620W WO 2017213581 A1 WO2017213581 A1 WO 2017213581A1
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Prior art keywords
substrate
nanotubes
material according
layer
noble metal
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PCT/SE2017/050620
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English (en)
Inventor
Thomas WÅGBERG
Xueen JIA
John Berge
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Wågberg Thomas
Jia Xueen
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Publication of WO2017213581A1 publication Critical patent/WO2017213581A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/158—Carbon nanotubes
    • C01B32/16—Preparation
    • C01B32/162—Preparation characterised by catalysts
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers

Definitions

  • a nanostructured material comprising a solid substrate surface with a plurality of nanoprotrusions and domains comprising at least one noble metal with sknnlataneous improvements in conductivity and
  • LOC Lab-on-a Chip
  • a multifunctional microiiuidic device that can be used to detect enzymatic and immunoassays optically and/or electrochemically is highly desirable.
  • a plasmonic metal layer should be generated on a multiple: electrode array or in the channel of microfluidics chip, which can be used for a number of potential diagnostic applications, since the biochips can be loaded with corresponding biomarkers, which after "reacting" with certain target molecules in the body fluidics will change the electrochemical or optical response on the device and therefore generate a measurable signal and after piasmonic modification, such. response will be significantly enhanced.
  • nanoarrays wherein nanosteed tubes are deposited on substrates and functionaiized as sensors.
  • US 2015/0210549 describes carbon nanotubes (CNTs) are grown on or attached to a substrate surface.
  • vapor deposition technologies CVD or PHCVD
  • Such tubes can be former funetionaiized with domains of noble metal or other chemical means.
  • the present invention generally relates to a. nanostruetured materia] comprising a solid substrate surface with a plurality of nanoprotrustons and domains comprising at least one noble metal that both exhibits a conducti ty (vertically and horizontally) and supports plasinonic resonance or SERS (Surface Enhanced Raman Scattering) enhancement, in order to be simultaneously suitable for both electrochemical and optical detection methods.
  • a. nanostruetured materia comprising a solid substrate surface with a plurality of nanoprotrustons and domains comprising at least one noble metal that both exhibits a conducti ty (vertically and horizontally) and supports plasinonic resonance or SERS (Surface Enhanced Raman Scattering) enhancement, in order to be simultaneously suitable for both electrochemical and optical detection methods.
  • SERS Surface Enhanced Raman Scattering
  • nanoportrusions of the nanostructural material is less than 50 nm, preferably 10 to 50 nm; and the conductivity of the .material estimated as vertical resistivity to 1 x 10 -4 Ohm*m and estimated as sheet resistance of 0.1 to .1 kOhm square.
  • the nanostruetured material comprises on the substrate a buffering layer, a catalyst layer on the buffering layer arid carbon nanotubes prepared by a chemical vapor deposition (CVD) method.
  • the buffering layer preferably has at least the double thickness of the catalyst layer and the catalyst layer is about 2 to about 15 nm thick.
  • the buffer layer can be a metal film of at least one of Al, Ti , Mo, Ta, Cr, Au, Pt and W, preferably the buffering layer comprises titanium.
  • the buffering layer can have a thickness of 4 to 50 mn. In one exampel, the buffering layer is 10 nm thick, preferably 5 nm thick and the catalyst layer is less than 15 nm thick.
  • the catalyst layer comprises iron, or an alloy of iron and another metal, preferably an alloy of iron and cobalt.
  • the catalyst layer can be treated with ammonia gas before perforating the chemical vapor deposition.
  • the nanotubes according this aspect cab have a length of approximately from 100 nm to 50 ⁇ m, preferably 100 nm to 1000 nm.
  • the the nanosturtured material generally has a density so the nanotube. to nanotube: distance is less than 50 nm.
  • Nanotubes according this aspect should have wide meaning and include carbon nanofibers (CNF), helical carbon nanofiber (HCNF), multi-walled carbon nanotabes (MWNTs), nitrogen doped multi- walled carbon nanotabes (N-CNTs) single-walled carbon nanotubes (SWCNT), ordered mesoporous carbon or graphefte,.
  • CNF carbon nanofibers
  • HCNF helical carbon nanofiber
  • MWNTs multi-walled carbon nanotabes
  • N-CNTs nitrogen doped multi- walled carbon nanotabes
  • SWCNT single-walled carbon nanotubes
  • ordered mesoporous carbon or graphefte ordered mesoporous carbon or graphefte
  • the nanotubes are multiwalled carbon nanotubes (MWNTs).
  • the nanotubes preferbly are nitrogen doped carbon nanotubes.
  • the nanostructured material according to this aspect can be prepared by providing a solid subsirate, optionally eompnsing an electrode pattern, with a buffering layer and a catalyst layer; growing on die so provided substrate, by chemical vapor deposition a vertically aligned carbon nanosiructure forest of nanotubes and thereby introducing nitrogen functionalities on said nanotubes; and finally anchoring noble metal nanopartic.es to the nanotubes to the nitrogen functionalities.
  • the noble metal domains according to this aspect can be of gold and/and silver and can be arrayed on the nitrogen doped carbon nanostructures with techniques, such as thermal evaporation (referred to as physical vapor deposition in high-vacuum systems below) or wet chemical methods, wherein a gold or silver salt is reduced by a reducing agent together with the nitrogen doped carbon nanostructures.
  • the noble metal can be represented by nanoparticles homogenously distributed on the nanostructures.
  • the nanostmctured. material has the SERS enhancement factors (EF) of at least 9x10 6 and at least 2,7x 10 5 , for domains of gold and silver, respectively, when calculated by comparing the Raman signal for a 4- ATP adsorbed on the material provided with nitrogen doped carbon nanostructures and NCNT/Au Features and the Raman signal for 4-ATP on a non-piasrnonie silicon dioxide substrate.
  • EF SERS enhancement factors
  • the nanostructured material generally described above wi th a high density of nanoprotrusions is be prepared by nanoimprinting
  • NIL lithography
  • a polymeric material cast on a substrate optionally comprising an electrode pattern
  • a hard mold containing a nanoscale surface relief obtaining a pattern of solid nanopillars on said substrate surface with a. length of 50 to 400 nm, preferably 50 to 200 nm; optionally removing residua! polymeric material; and introducing a noble metal film to provide nanostructured material with the noble metal domains.
  • the noble metal domains can be introduced with methods similar to what has been described above with the carbon nanotubes.
  • the step of contacting the cast with .mold can comprise heating a transparent thermoplastic polymer having a glass transition temperature of 60- 100 °C and applying a pressure of 5 to 60 bar.
  • polyethylene terephthalaie PET
  • the conditions are requirements for this technology is described further U Guo, 2007, Adv. Mater., Vol 19, pp 495-513.
  • the material of this aspect has SERS enhancement factors (EF) of at least 2.5x10 5 , for noble domains of silver, when calculated by comparing the Raman signal for a 4-ATP adsorbed on the- material and the Raman signal for 4-ATP on a iion-plasmonic silicon dioxide substrate.
  • SERS enhancement factors EF
  • the materials according to the described aspects are suitable for being included in a multifunctional biociiip with an electrochemical and an optical detection zone and thereby perioral simultaneous and/or comparative measurements.
  • the biochip comprises a substrate comprising an electrode pattern for establishing an electrochemical detection zone, wherein the substrate is provided- with the nanostmetures according to the present invention having domains of noble metal with at least one immobilized biomarker for establishing an optical detection zone, and wherein the biochip has a microfluidic system comprising a port adapted to receive a fluid sample, a first, fluid channel for transporting sample fluid to the electrochemical detection zone and second fluid channel for transporting fluid to the optical detection zone.
  • the biochip can have the micro fluidic system present in a layer added to the substrate, or the microtluidic system can be present in the substrate.
  • Fig. 1 depicts Scanning electron microscopy (SEM) images of vertically aligned nitrogen doped carbon nanotubes (NCNTs) grown on a) SiO2 substrate -coated with a Ti buffer layer and a catalyst layer comprising a 1: 1 Fe/Co alloy thin film.
  • SEM Scanning electron microscopy
  • Fig 1b depicts a SiO2 substrate with a catalyst layer comprising a. 1 :1 Fe/Co alloy thin film but without a buffer layer.
  • the figures show that the NCNT forest prepared with a buffer layer is much denser and more homogeneous compared to the NCNT forest synthesized without buffer layer (note that the scale bar in the images are the same).
  • a buffer layer works like a spacer between catalyst and substrate: avoiding catalyst particles penetrate or escape from the substrate.
  • Fig 2a and 2b respectively depicts Scanning electron microscopy (SEM) images with Fig 2a low magnitude (zoom-out perspective and Fig 2b high magnitude (zoom-in perspective) of vertically aligned nitrogen doped carbon nanotubes (NCNTs) grown on SiO2 substrate coated with a Ti buffer layer and a catalyst layer comprising a 1 :1 Fe/Co alloy thin film after depositing and annealing a Ag thin film on top of the NCNTs,
  • SEM scanning electron microscopy
  • the presence, morphology and, size of the nanodomains formed on the NCNTs result in two targeted purposes; i) plasmonk resonances for wavelengths in visible range (500-700 run) leading to an enhanced Raman or fluorescence signal, and ii) conducting bridges, leading to a horizontally conducting pathway (percolation path) between tube and tube.
  • the CNT forests were grown from a catalyst metal layer through a C VD process at 800 °C and a physical vapor deposition (PVD) and annealing processes were applied subsequently for the evaporation and diffusion of noble metal nanoparticles on the forest.
  • PVD physical vapor deposition
  • Electrodes patterning were made onto the silicon-oxide (SiO2) wafers through the photoiitliography process with and without depositing buffer layer on the Si-surfaces.
  • Photolithography is selected as a process oftransferring geometric shapes on a mask to the surface of a silicon wafer.
  • Si-wafers were cleaned by soni cation in acetone, ethanot and water for 20 min separately, and then blow dry by N2 blowing and cleaned again by pi asma cleaner with UV and ozone for 25 minutes.
  • a photoresist was added to the surface of each wafer and kept them spinning separately by a spin coater at 4000 rpm: (or 1000 rpm/sec) for one minute.
  • each wafer was hot baked in a portable oven at 1 10 °C for 1 minute.
  • a mask aligner was used as a source of radiation which produces a typical mercury spectrum with the highest intensity at the H-line (404.7 nm), see the article "Growing patterned vertically aligned nitrogen-doped carbon nanotubes (VAN-CNTs) by CVD and photolithography, Author: Joakim Ekspong, 2014-06-09, Department of Physics, Umea University, Sweden".
  • the exposure time for the mask aligner was set to 25 seconds.
  • the electrode patterns were pre-printed on an opaque plate which- was used as a photomask for patterning. After exposing a high intensity ultraviolet light to the mask, the electrode patterns were burned into the photoresist on the wafers, see
  • the buffering layer is found to have critical role with the thickness of catalyst on the density of the NCNT forest production. Generally, it is found herein that the buffermg layer hinders catalysts to partially diffuse into the substrate (silicon) an that it enables forming of appropriate catalyst particles on the silicone substrate,
  • a titanium (Ti) buffering layer with thickness of 10 nm were deposited by physical vapor deposition (Physical vapor deposition (PVD) is a vaporization coating process which is carried out in high vacuum pressure at any temperature between 150 and 500 °C, see
  • the pretreatment step with ammonia (NH3) in the CVD is performed in accordance with T. Sharifi et al. in Carbon, 50, 3535-3541 (2012), used to grow CNTs and NCNTs with uniform diameters on a Si-substrate.
  • Time duration of the NH3 treatment according to the presently exemplified invention is about 20 minutes.
  • Pyridine was used as carbon and nitrogen precursor for the CNT growtli and the height of the forest can be controlled by the growth time (the time at which the precursor is introduced in the CVD oven while maintaining a temperature high enough to decompose the precursor). In the present example below 20 and 60 minutes, were used respectively.
  • a silver (Ag) film deposition on top of the N-doped CNTs is made by forming a 30 nm Ag layer on top of the CNTs by running a premade recipe in the thermal PVD process in the clean room.
  • the Ag-evaporated samples were placed into a quartz tube and annealed at a temperature of 400 0C in the electric oven for 30 minutes.
  • the varigon was kept at a rate of 180 ml/mm during the annealingtime and after the heat treatment the oven was cooled down to 80 °C with keeping the flow of Ar instead at a rate of 180 ml/min.
  • a goid (Au) film deposition on top of the N-doped CNTs is made by a forming 30 mil Au layer- oft top of the CNTs by running a premade recipe in the tfterrnal PVD process in the clean room.
  • the Au-evaporated samples were placed into a quartz tube and annealed at a temperature of 800°C in the electric oven for 10 minutes.
  • the varigon was kept owing at a rate of 1 80 ml/min during the annealing time and after the heat treatment, the oven was cooled down to 80°C with keeping the flow of Ar instead at a rate of 1 SO ml/min.
  • SERS is a surface-sensitivetechnique that enhances Raman scattering, by molecules adsorbed on rough metal surfaces or by nanostructures.[ Xu, X., Li, EL, Hasan, D., Ruoff, R. S., Wang, A. X. and Fan, D. L. (2013), Near-Field Enhanced Plasmonic- Magnetic Bifunctional Nanotubes for Single Cell Bioanalysis. Adv.
  • the SERS enhancement factors were calculated by comparing the Raman signal for a 4-ATP adsorbed on .the functional SERS substrate (the substrate with plasmonic NCNT/Au features) and the Raman signal of 4- ATP on a traditional non-plasmonic substrate.
  • the calculated values of EF from Ag- and Au-coated CNT forests were 9x 10 6 and 2.7x 10 5 respectively. Accordingly, the peak intensity at wave number of 1076 cm-1 was picked up from each SERS spectra to establish the Ag- and Ati-trend curves with different concentrations of 4- ATP solutions.
  • Fig. 1a and Fig 1b are SEM images showing that the NCNT forest prepared with buffer layer is much denser and smooth compared to the NCNT forest synthesized without buffer layer (note that the scale bar in the images are the same).
  • a buffer layer works like a spacer between catalyst and substrate avoiding catalyst particles penetrate or escape from the substrate.
  • Example2 The nanoimprinting is made by first, i) heating a polymer film.
  • PET polyethyelene terepthtalate
  • the mold can be varied according to the pattern that is desired to press into the polymer substrate.
  • the polymer substrate can be varied as long as the glass transition is suitable (60-100 °C).
  • the nanopillars are a pressure of 30 bar and a temperature of 80 degrees were used.
  • SEM scanning electron microscopy
  • the nanopillars are shown as bright spots protruding from the SiO2 substrate.
  • the pillars are uniform, and are approximately 200 nra high (height can be controlled by varying parameters such as pressure and time), have diameters of 50 nm and have a center-to-center distances of 100 nm.
  • a iianostructured material is estamated to have SER S enhancement factors ( EF) of at. least 2.5 x 10 3 , for domains of silver, when, calculated by comparing the Raman signal for a 4- ATP adsorbed on the material and the Raman signal for 4-ATP on a non- plasmome silicon dioxide substrate.
  • EF SER S enhancement factors

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Abstract

L'invention concerne un matériau nanostructuré comprenant une surface de substrat solide dotée d'une pluralité de nano-saillies et de domaines comprenant au moins un métal noble présentant des améliorations simultanées de conductivité et de réponse électromagnétique par résonance plasmonique. L'invention concerne également des procédés de dépôt chimique en phase vapeur et des procédés de nano-impression permettant de préparer ce matériau nanostructuré.
PCT/SE2017/050620 2016-06-10 2017-06-09 Matériau nanostructuré WO2017213581A1 (fr)

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SE1650817-8 2016-06-10

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111799448A (zh) * 2019-04-08 2020-10-20 江苏天奈科技股份有限公司 一种硅或其氧化物原位长碳纳米管的方法
CN112875677A (zh) * 2021-01-20 2021-06-01 军事科学院系统工程研究院卫勤保障技术研究所 负载有金属纳米颗粒的有序介孔碳的制备方法，其产品及应用
CN114113034A (zh) * 2021-11-17 2022-03-01 肇庆市华师大光电产业研究院 一种多壁碳纳米管“手指”的制备方法及其在表面增强拉曼散射检测中的应用

Citations (2)

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US20130089735A1 (en) * 2011-01-07 2013-04-11 KAIST (Korea Advanced Insitute of Science and Tech Method for preparing inorganic-nanostructure composite material, method for preparing carbon nanotube composite using same, and carbon nanotube composite prepared thereby
US20150210549A1 (en) * 2012-03-09 2015-07-30 Johan Johansson Covalent functionalization of carbon nanotubes grown on a surface

Patent Citations (2)

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US20130089735A1 (en) * 2011-01-07 2013-04-11 KAIST (Korea Advanced Insitute of Science and Tech Method for preparing inorganic-nanostructure composite material, method for preparing carbon nanotube composite using same, and carbon nanotube composite prepared thereby
US20150210549A1 (en) * 2012-03-09 2015-07-30 Johan Johansson Covalent functionalization of carbon nanotubes grown on a surface

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J ZAHANG ET AL.: "In situ assembly of gold nanoparticles on nitrogen-doped carbon nanotubes for sensitive immunosensing of microcystin- LR", CHEM. COMMUN., vol. 47, 2011, pages 668 - 670, XP055454911 *
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111799448A (zh) * 2019-04-08 2020-10-20 江苏天奈科技股份有限公司 一种硅或其氧化物原位长碳纳米管的方法
CN112875677A (zh) * 2021-01-20 2021-06-01 军事科学院系统工程研究院卫勤保障技术研究所 负载有金属纳米颗粒的有序介孔碳的制备方法，其产品及应用
CN114113034A (zh) * 2021-11-17 2022-03-01 肇庆市华师大光电产业研究院 一种多壁碳纳米管“手指”的制备方法及其在表面增强拉曼散射检测中的应用

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