KR20160047022A - Preparation of Triple layered core shell nano particles and a sollar cell comprising the same - Google Patents

Abstract

Provided is a triple layered core-shell nanoparticles comprising a metal nanoparticle core, a dielectric shell surrounding the metal nanoparticles; and a semiconductor shell surrounding the dielectric shell. According to the present invention, a triple layered core shell composed of metal particles-dielectric-semiconductor is applied inside an electron transfer layer of a solar cell. By coating the semiconductor shell on plasmon particles, the triple layered core shell can enhance electron transfer performance without reducing surface plasmon resonance (SPR) effect on the surface of metal nanoparticles by coating the semiconductor shell on plasmon particles, thereby obtaining an improved optical conversion efficiency of a solar cell.

Description

Preparation of Triple Core Shell Nanoparticles and Preparation of Triple Layered Core Shell Nanoparticles < RTI ID = 0.0 >

The present invention relates to the production of triple core shell nanoparticles and solar cells comprising the same.

Recently, as the exhaustion of existing energy resources such as oil and coal is predicted, interest in energy to replace them is increasing. In particular, solar cells are attracting particular attention because they are rich in energy resources and have no problems with environmental pollution.

Most of the solar cells that have been put to practical use as a new energy source are inorganic solar cells using inorganic materials such as monocrystalline silicon, polycrystalline silicon, and amorphous silicon. However, since inorganic solar cells have a complicated manufacturing process, they are not suitable for general household use because of high manufacturing cost. Therefore, research on organic solar cells that require less manufacturing cost than a manufacturing process of inorganic solar cells Is actively proceeding.

The organic solar cell basically has a thin-film structure and does not require high-temperature heat, so an ITO substrate having a low resistance is generally used. On the ITO substrate, a conductive polymer layer is formed to enhance a buffering action and a hole-transporting effect between the photoactive layer and the electrode.

In addition, a photoactive layer is formed on the conductive polymer layer, and the photoactive layer includes a p-type semiconductor polymer serving as an electron donor and a bulk of n-type organic molecules serving as an electron acceptor. And may be formed by bulk heterojunction.

Finally, an organic solar cell is completed by forming a metal electrode on the photoactive layer, and conductive metal such as silver or aluminum can be used as the metal electrode.

When light is incident on the photoelectric conversion layer of such an organic solar cell, electrons and holes are excited in the electron donor and electrons are transferred to the electron transport layer, resulting in separation of electrons and holes. Therefore, the carriers generated by the light are separated by the electron-hole, and the electric power is generated as the carrier moves to the external circuit.

At this time, as the electron transporting layer, metal oxides such as cesium carbonate (Cs ₂ CO ₃ ), titanium oxide (TiO _x ) and zinc oxide (ZnO) are prepared for improving electron transfer and charge extraction come.

Particularly, zinc oxide (ZnO) is widely used as an electron transport layer (ETL) of an inverted solar cell because of its high electron mobility and light transmittance in a visible region.

However, although the improvement of the light conversion efficiency of the organic solar cell has been advanced recently, it is difficult to commercialize the organic solar battery due to its low efficiency, and it is necessary to improve the efficiency.

In the field of organic solar cells, studies for improving the efficiency have been actively carried out. In order to overcome the selection or manufacturing process of the photoactive layer or the electron transport layer and the hole transport layer to effectively utilize the absorbed light or the low charge mobility Studies on the morphology, structure and crystallinity of organic thin films have been conducted.

For example, Korean Patent No. 10-1131564 provides a method for producing a photoactive layer solution for an organic solar cell containing core / shell metal oxide nanoparticles.

The photoactive layer solution includes p-type metal nanoparticles coated with an n-type metal oxide, which is a core / shell structure, and has the effect of manufacturing an organic solar cell by using a simple wet process using the photoactive layer solution There is a bar.

The inventors of the present invention have been studying materials that can be used as an electron transport layer for improving the photovoltaic characteristics of an organic solar cell, and have found that a dielectric shell surrounding a metal nanoparticle core and a semiconductor shell surrounding the dielectric shell The present inventors have completed the present invention by developing a triple core shell nanoparticle containing the triple core shell nanoparticle and a solar cell using the same.

An object of the present invention is to provide a triple core shell nanoparticle and a solar cell including the same.

In order to achieve the above object,

The present invention

Metal nanoparticle cores;

A dielectric shell surrounding the metal nanoparticles; And

And a semiconductor shell surrounding the dielectric shell.

Also,

Preparing metal core nanoparticles (step 1);

Forming a dielectric shell on the surface of the metal nanoparticle core of step 1 (step 2); And

And forming a semiconductor shell on the surface of the metal-dielectric core shell of step 2 (step 3).

Also,

Board; cathode; An electron transport layer; A photoactive layer; A hole transport layer; And a positive electrode,

Wherein the electron transport layer comprises the triple-core-shell nanoparticles of the first aspect and the semiconductor oxide nanoparticles.

Further,

Forming a cathode layer on the substrate (Step 1);

A step (step 2) of forming an electron transporting layer containing triple core shell nanoparticles and semiconductor oxide nanoparticles;

Forming a photoactive layer (step 3);

Forming a hole transporting layer (step 4); And

And a step of forming an anode layer (step 5).

The present invention applies a triple-core shell made of a metal particle-dielectric-semiconductor material to an electron transport layer of a solar cell. By coating a semiconductor shell on a plasmon particle, the charge transporting capability of the metal nanoparticle without decreasing the surface plasmon resonance (SPR) And as a result, an improved light conversion efficiency of the solar cell can be obtained.

1 is a photograph of a triple core shell nanoparticle according to the present invention observed through a transmission electron microscope (TEM);
FIG. 2 is a photograph of the triple core shell nanoparticles prepared in Examples 1 and 2 through a transmission electron microscope; FIG.
3 is a photograph of a metal nanoparticle and a metal nanoparticle-dielectric double core shell observed through a transmission electron microscope;
4 is a photograph of a thin film of the electron transporting layer in the solar cell manufactured in Example 3 and Comparative Examples 2 and 3 through a scanning electron microscope (SEM);
5 is a graph showing the absorbance of the solar cell manufactured in Example 3 and Comparative Example 3 through an ultraviolet-visible (UV-Vis) spectrometer;
FIG. 6 (a) is a graph showing the current density-voltage curves of the solar cells manufactured in Examples 3 to 5 and Comparative Examples 1 to 3, FIG. 6 (b) is a graph showing the external quantum efficiecy (EQE) Fig.

Hereinafter, the present invention will be described in detail.

The present invention

Metal nanoparticle cores;

A dielectric shell surrounding the metal nanoparticles; And

And a semiconductor shell surrounding the dielectric shell.

The metal nanoparticles are preferably metal nanoparticles exhibiting surface plasmon resonance, and examples thereof include gold (Au), silver (Ag), copper (Cu), aluminum (Al), platinum (Pt) ) May be used, and preferably silver (Ag) nanoparticles.

Surface plasmons are particles in which free electrons oscillate collectively on the surface of a metal. In metal nanoparticles, the absorption of light is caused by the combination of the electric field of visible light and near-infrared light with the plasmon. This phenomenon is called surface plasmon resonance (SPR).

Among the metals used for surface plasmon resonance, gold (Au), silver (Ag), and copper (Cu) are used as the most common metals in the field of solar cells. It is preferred to use surface plasmon metals because these metals have been shown to exhibit resonance in the visible or near infrared region of the electromagnetic spectrum, and their use has been shown to increase their optical absorption.

In addition, to form the dielectric shell surrounding the metal nanoparticles, the dielectric may be selected from the group consisting of silicon oxide, titanium oxide, zirconium oxide, strontium oxide, lanthanum oxide, vanadium oxide, (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, niobium oxide, magnesium oxide, aluminum oxide, yttrium oxide, scandium oxide , A metal oxide such as a samarium (Sm) oxide and a strontium titanium (SrTi) oxide, and preferably a silicon oxide, but is not limited thereto.

At this time, as a precursor for forming the silicon oxide shell, tetramethylorthosilicate, tetraacetoxysilane, tetraethylorthosilicate, tetramethoxysilane, tetrapropoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, Phenyltrimethoxysilane, methyltriethoxysilane, methylacetoxysilane, phenyltrimethoxysilane, and the like can be used.

Meanwhile, the thickness of the dielectric shell can be controlled by controlling the dielectric oxide precursor and the solvent, and the diameter of the triple core shell nanoparticles is preferably 5 to 70 nm.

If the particle diameter is less than 5 nm A trapping phenomenon of the metal core may be generated and the charge transport ability may be deteriorated. When the diameter of the particles exceeds 70 nm, the thickness of the semiconductor layer may exceed the thickness of the semiconductor layer and the roughness ), And the surface plasmon resonance (SPR) effect of the metal particles of the core is inversely proportional to the distance, so that the SPR effect can be reduced.

(The In the embodiment  Based on the size of the particle, the range is 30-70 nm However, please refer to the amendment of the specification sent, nm .

Wherein the semiconductor surrounding the dielectric shell comprises one or more semiconductor oxides selected from the group consisting of zinc (Zn) oxide, gallium (Ga) oxide, indium (In) oxide, tin (Sn) oxide, and titanium But is not limited thereto.

In the present invention, the surface plasmon resonance effect of the metal core particles is not deteriorated by forming the semiconductor shell, thereby increasing the light absorptivity and enhancing the electron transporting ability in the solar cell to obtain improved light conversion efficiency have.

In the triple core shell nanoparticles according to the present invention, the metal nanoparticles may be silver nanoparticles, the dielectric shell may be silicon oxide, and the semiconductor shell may be triple core shell nanoparticles of zinc oxide, 1 (a).

Also,

Preparing metal core nanoparticles (step 1);

Forming a dielectric shell on the surface of the metal nanoparticle core of step 1 (step 2); And

And forming a semiconductor shell on the surface of the metal-dielectric core shell of step 2 (step 3).

In the preparation of the triple-core-shell nanoparticles according to the present invention, the metal nanoparticles are preferably metal nanoparticles exhibiting surface plasmon resonance.

For example, gold (Au), silver (Ag), copper (Cu), aluminum (Al), platinum (Pt), and nickel (Ni) as and the like, of which silver (Ag) precursor is AgBF _4, AgCF ₃ SO ₃ , AgClO ₄ , AgNO ₂ , AgNO ₃ , Ag (CH ₃ COO), AgPF ₆ and Ag (CF ₃ COO)

At this time, the metal nanoparticles can be synthesized through the precursor solution of each metal nanoparticle and the chemical reducing agent.

For example, silver ions (Ag ⁺⁾ may be used silver nitrate (AgNO ₃₎ solution as the precursor, a reducing agent as PVP (polyvinylpyrollidone), the hydroquinone (hydroquinone), ascorbic acid salts, citric acid salts, sodium borohydride (Sodium borohydride) can be used as a metal borohydride solution.

The type and concentration of the silver ion (Ag ⁺ ) precursor and the kind and concentration of the reducing agent may be appropriately selected according to the particle size, and the concentrations may be in the range of 0.001 M to 10 M, respectively. Gold nanoparticles of one size are not formed, and gold nanoparticles may not be formed if the size is less than the above range. However, these kinds and concentrations are not limited in the present invention.

Meanwhile, step 2 is a step of forming a dielectric shell on the surface of the metal nanoparticle core produced in step 1, wherein the dielectric nanoparticle solution and the dielectric oxide precursor solution are mixed and stirred to form a dielectric shell.

The particles thus formed can also be re-dispersed after centrifugation and washing to produce a metal-dielectric double core shell.

The dielectric oxide may be a metal oxide and may be a silicon oxide, a titanium oxide, a zirconium oxide, a strontium oxide, a lanthanum oxide, a vanadium oxide, a molybdenum oxide, (Mo) oxide, tungsten (W) oxide, niobium oxide, magnesium oxide, aluminum oxide, yttrium oxide, scandium oxide, A metal oxide such as titanium (SrTi) oxide may be used, and preferably it may be a silicon oxide.

At this time, as a precursor for forming a silicon oxide shell, tetramethylorthosilicate, tetraacetoxysilane, tetraethylorthosilicate, tetramethoxysilane, tetrapropoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, phenyl A precursor such as trimethoxysilane, methyltriethoxysilane, methylacetoxysilane, phenyltrimethoxysilane and the like can be used.

The solvent used for the metal oxide precursor solution is preferably selected from among ethanol, methyl alcohol, ethyl alcohol, tetrahydrofuran (THF), and distilled water. The thickness of the shell is adjustable.

Meanwhile, step 3 is a step of forming a semiconductor shell on the surface of the metal-dielectric core shell formed in step 2, and may be formed by culturing a mixture of metal-dielectric core-shell nanoparticles and a semiconductor oxide.

At this time, the semiconductor may be at least one semiconductor oxide selected from the group consisting of zinc oxide, gallium oxide, indium oxide, tin oxide, and titanium oxide. And preferably zinc oxide (ZnO).

For example, after the metal-dielectric core-shell nanoparticle solution prepared in step 2 is dispersed in a PVP solution, a hardening agent such as hexamethylenetetramine (HMTA) and zinc nitrate (Zn (NO ₃ ) ₂ ) The mixture may be incubated at a temperature of 90 to 110 for 3 hours to form a triple-core-shell nanoparticle composed of a metal-dielectric-semiconductor, which may have a structure as shown in FIG. 1 (a).

Also,

Board; cathode; An electron transport layer; A photoactive layer; A hole transport layer; And a positive electrode,

Wherein the electron transport layer comprises triple-core-shell nanoparticles and semiconductor oxide nanoparticles.

The organic solar cell according to the present invention includes an electron transport layer including the cathode and the triple core shell nanoparticles on the anode, and a photoactive layer, a hole transport layer, and a cathode stacked on the electron transport layer.

At this time, the triple-core-shell nanoparticles and the semiconductor oxide nanoparticles according to the present invention may be mixed and then coated on the cathode to form an electron transport layer.

The semiconductor oxide nanoparticles may be at least one semiconductor oxide selected from the group consisting of zinc (Zn) oxide, gallium (Ga) oxide, indium (In) oxide, tin (Sn) oxide, and titanium , Preferably zinc oxide (ZnO).

At this time, the precursor of zinc oxide may include at least one selected from the group consisting of zinc citrate dihydrate, zinc acetate, zinc acetate dihydrate, zinc acetylacetonate hydrate Zinc acetylacetonate hydrate, Zinc acrylate, Zinc chloride, Zinc diethyldithiocarbamate, Zinc fluoride, Zinc dimethyldithiocarbamate, Zinc fluoride hydrate, Zinc hexafluoroacetylacetonate dihydrate, Zinc nitrate hexahydrate, Zinc methacrylate, zinc nitrate hydrate, (Zinc nitrate hydrate) and zinc perchlorate Can use a hexahydrate (Zinc perchlorate hexahydrate), it may be preferably zinc acetate dihydrate.

The mixed solution of the triple core shell nanoparticles and the semiconductor oxide nanoparticles may be prepared by adding 0.5 to 2% by weight of the triple core shell particles to the mass of the semiconductor oxide particles.

If the concentration of the triple core shell particles is less than 0.5 wt% or exceeds 2 wt%, the efficiency of the solar cell may be lowered due to a decrease in surface plasmon resonance effect or an increase in surface roughness.

Also,

Forming a cathode layer on the substrate (Step 1);

(Step 2) of forming an electron transport layer comprising triple-core-shell nanoparticles and semiconductor oxide nanoparticles;

Forming a photoactive layer (step 3);

Forming a hole transporting layer (step 4); And

And a step of forming an anode layer (step 5).

The first step is to form a cathode layer on the substrate,

The substrate is not particularly limited as long as it has transparency and may be a transparent inorganic substrate such as quartz or glass or a transparent substrate such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polystyrene (PS) PP), polyimide (PI), polyethylene sulfonate (PES), polyoxymethylene (POM), polyetheretherketone (PEEK), polyether sulfone (PES) and polyetherimide Any one transparent plastic substrate can be used.

As the material for forming the cathode layer, tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), ZnO-Ga ₂ O ₃ , ZnO-Al ₂ O ₃ , SnO ₂ -Sb ₂ O _3, and combinations thereof. ITO may be preferably used.

Step 2 is a step of forming an electron transport layer including triple-core-shell nanoparticles and semiconductor oxide nanoparticles,

The electron-

Preparing triple core shell nanoparticles (step A);

Producing semiconductor oxide nanoparticles (step B);

Preparing a mixed solution of triple core shell particles and semiconductor oxide nanoparticles (step C); And

And coating the mixed solution of Step C on the cathode layer (Step D).

In the step C, the mixed solution may be prepared by adding 0.5 to 2 wt% of triple-core-shell nanoparticles to the mass of the semiconductor oxide nanoparticles prepared in the step A above.

The step D is a step of coating the mixed solution prepared in the step C on the cathode layer and may be coated by spin coating, drop-casting or the like to form a thin film.

In addition, the electron transport layer including the core-shell particles having a triple structure can increase the light absorption efficiency of the nanoparticles due to surface plasmon resonance and alleviate the reduction of the surface plasmon resonance effect through the triple structure through the semiconductor shell coating The electron transport ability in the solar cell can be improved.

In the method for manufacturing a solar cell according to the present invention, the active layer is formed of [6,6] -phenyl-C60 butyric acid methyl ester (PCBM), oly [2-methoxy-5 - (2'-ethylhexyloxy) -p-phenylene vinylene] (MEH-PPV), poly (3-hexylthiophene (P3HT) and poly [N-9 "-hepta-decanyl-2,7- - (4 ', 7'-di-2-thienyl-2', 1 ', 3'-benzothiadiazole)] (PCDTBT). Preferably, P3HT and PCBM are mixed .

The positive hole transporting layer may be one selected from the group consisting of molybdenum trioxide (MoO ₃ ), chromium oxide (CrO _x ), vanadium pentoxide (V ₂ O ₅ ), and NiO. Au, nickel (Ni), or the like may be used. The hole transport layer and the anode layer may be formed through vapor deposition.

Hereinafter, preferred embodiments according to the present invention will be described in detail. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Example 1 Production of Triple Core Cell Particles 1

Step 1: To prepare silver nanoparticle cores, silver nitrate (AgNO ₃ ), a silver precursor, was dissolved in a mixed solution of ethanol and water at a temperature of 75 ° C or higher, and then 2.5 mM of polyvinylpyrrolidone polyvinylpyrollidone (PVP) aqueous solution and 0.1 M sodium hydroxide (NaOH) solution, and the mixture was stirred at 75 캜 for 5 minutes. After that, silver nanoparticles were prepared by cooling at room temperature.

Step 2: In order to form a silicon oxide shell on the silver nanoparticles, 5 ml of ethanol was added to 20 ml of the silver nanoparticle solution prepared in the step 1, and 0.5 ml of ammonia solution and 0.108 ml of tetraethoxysilane (TEOS) After the mixture was slowly added, the mixture was rapidly stirred at room temperature for 15 hours.

The thus formed particles were centrifuged at 20,000 rpm for 20 minutes and then redispersed after washing to prepare a silver-silica core shell nanoparticle solution.

Step 3: In order to form a zinc oxide shell on the surface of the silicon oxide shell surrounding the silver nanoparticle core, the silver-silica core cell nanoparticles (0.05) mg prepared in the above step 2 were dissolved in a polyvinylpyrrolidone (PVP) solution 2 ml, and mixed with a small amount of hexamethylenetetramine (HMTA).

Then, 50 uL of zinc nitrate (Zn (NO ₃ ) ₂ ) was added, and the mixture was incubated at 100 ° C for 3 hours.

The thus-formed particles were centrifuged at 10,000 rpm for 20 minutes and re-dispersed after washing to prepare Ag-SiO ₂ -ZnO triple core shell nanoparticles coated with a zinc oxide shell on the surface of the silver-silica core cell.

≪ Example 2 > Preparation of triple core cell particles 2

In the same manner as in Example 1, except that 2.0 ml of the ammonia solution and 0.036 ml of tetraethoxysilane (TEOS) were used in Example 2, the Ag-SiO ₂ -ZnO triple core Shell nanoparticles were prepared.

≪ Example 3 > Preparation of electron transport layer containing triple core shell nanoparticles and solar cell using the same

Step 1: To prepare zinc oxide (ZnO) nanoparticles, 1 mmol of zinc precursor zinc acetate dehydrate (ZnOAc) was added to methanol together with 1 g of potassium hydroxide (KOH) Lt; / RTI >

The resulting translucent zinc oxide nanoparticle solution was allowed to precipitate at room temperature, and was washed by centrifugation, and then redispersed in a mixed solution of chlorobenzene and isopropyl alcohol to prepare zinc oxide nanoparticles.

Step 2: 0.5% by weight of the triple core shell nanoparticles prepared in Example 1 was added to the mass of the zinc oxide nanoparticles prepared in the step 1 to prepare a mixed solution.

Step 3: A negative electrode layer was formed by coating a glass substrate with indium tin oxide (ITO), and then the mixed solution prepared in the step 2 was spin-coated on the negative electrode layer at a rate of 1000 rpm for 30 seconds, An electron transport layer in which core cell nanoparticles and zinc oxide nanoparticles were mixed was formed.

Step 4: A photoactive layer was formed on the electron transport layer using P3HT / PCBM.

Step 5: A thin film was formed on the photoactive layer by vapor deposition using MoO ₃ as the hole transport layer and Ag as the anode layer to complete the solar cell.

Example 4: Electron transport layer containing triple core shell nanoparticles and manufacture of solar cell using the same

A solar cell was manufactured in the same manner as in Example 3, except that 1 weight% of triple core shell nanoparticles was added to the mass of the zinc oxide nanoparticles in the step 3 of Example 3. [

Example 5 Electron Transport Layer Containing Ternary Core Shell Nanoparticles and Preparation of Solar Cell Applied therewith 3

A solar cell was manufactured in the same manner as in Example 3, except that 2 weight% of triple core shell nanoparticles were added to the mass of the zinc oxide nanoparticles in the step 2 of the Example 3.

≪ Comparative Example 1 > Production of solar cell including conventional electron transporting layer.

A solar cell was manufactured in the same manner as in Example 3, except that the triple-core shell was not included in the step 3 and the electron transporting layer was formed using only the zinc oxide nanoparticles.

≪ Comparative Example 2 > Preparation of electron transport layer containing metal nanoparticles and solar cell using the same

Step 1: To prepare silver (Ag) nanoparticles, a silver precursor, silver nitrate (AgNO ₃ ), was dissolved in a mixed solution of ethanol and water at a temperature of 75 ° C or higher at a constant concentration (0.05M). After that, 2.5 mM polyvinylpyrollidone (PVP) aqueous solution and 0.1 M sodium hydroxide (NaOH) solution were added, and the mixture was stirred at 75 ° C for 5 minutes and cooled at room temperature to prepare silver nanoparticles.

Step 2: The procedure of Example 3 was repeated except that the silver (Ag) nanoparticles prepared in Step 1 were added in an amount of 1% by weight based on the mass of the zinc oxide nanoparticles to prepare a mixed solution and then an electron transport layer was formed. The solar cell was manufactured in the same manner.

≪ Comparative Example 3 > An electron transport layer containing a double core shell nanoparticle and manufacture of a solar cell using the same

Step 1: To prepare silver nanoparticle cores, silver nitrate (AgNO ₃ ), a silver precursor, was dissolved in a mixed solution of ethanol and water at a temperature of 75 ° C or higher, and then 2.5 mM of polyvinylpyrrolidone polyvinylpyrollidone (PVP) aqueous solution and 0.1 M sodium hydroxide (NaOH) solution, and the mixture was stirred at 75 캜 for 5 minutes. After that, silver nanoparticles were prepared by cooling at room temperature.

Step 2: 5 ml of ethanol was added to 20 ml of the silver nanoparticle solution prepared in Step 2, and then 0.5 ml of ammonia solution, 0.108 ml of tetraethoxysilane (TEOS) was added to form a silicon oxide shell on the silver nanoparticles. And the mixture was rapidly stirred at room temperature for 15 hours.

The thus formed particles were centrifuged at 20,000 rpm for 20 minutes and then redispersed after washing, to prepare silver-silica core shell nanoparticles.

Step 3: The procedure of Example 3 was repeated except that 1 wt% of the silver-silica core nanoparticles prepared in the above step 2 was added to the mass of the zinc oxide nanoparticles to prepare a mixed solution and then an electron transport layer was formed. To prepare a solar cell.

≪ Comparative Example 4 > Preparation of electron transport layer containing triple core shell nanoparticles and solar cell using the same

A solar cell was fabricated in the same manner as in Example 3, except that 3 weight% of triple core shell nanoparticles were added to the mass of the zinc oxide nanoparticles in the step 2 of the Example 3.

<Experimental Example 1>

FIG. 1 (a) shows a photograph of the triple-core-shell nanoparticles prepared in Example 1 through a transmission electron microscope (TEM) and shows the structure of the Ag-SiO ₂ -ZnO triple core shell particle . FIG. 1 (b) shows the presence of Ag, SiO ₂ , and ZnO as observed by transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDX) of the triple core shell nanoparticles.

FIG. 2 is a photograph of the triple core shell nanoparticles prepared in Examples 1 and 2 through a transmission electron microscope. The nanoparticles of Example 1 had a diameter of 60 to 65 nm and the nanoparticles of Example 2 Is 35 to 45 nm.

As shown in FIG. 2, the size of the triple-core-shell nanoparticles can be controlled by controlling the thickness of the dielectric shell, and the diameter of the triple-core-shell nanoparticles according to the present invention is 30 to 70 nm have.

FIG. 3 is a photograph of a metal nanoparticle and a metal nanoparticle-dielectric double core shell, not a triple core shell, observed through a transmission electron microscope. FIG. 3 (a) -SiO ₂ A photograph of the nanoparticles is shown, and the structure of the double core shell can be observed.

In addition, the morphology of the electron transport layer in the solar cell manufactured in Example 3 and Comparative Examples 2 to 3 was observed through a scanning electron microscope (SEM) and is shown in FIG. As shown in FIG. 4, an electron transport layer having a uniform surface can be identified on the ITO surface.

<Experimental Example 3>

In order to evaluate the absorbance according to the particle structure of the electron transport layer of the solar cell, the absorbance was measured using an ultraviolet-visible (UV-Vis) spectrophotometer of the solar cell prepared in Example 3 and Comparative Example 3 And is shown in Fig.

As shown in Fig. 5, in Example 3 using triple core shell particles as an electron transporting layer, the absorbance was higher than that of the solar cell of Comparative Example 3 in which the double core shell particles were used as the electron transporting layer.

5, by applying the triple-core shell particle including the zinc oxide semiconductor shell as the electron transport layer, it is possible to predict the increase of the light absorption of the solar cell and the improvement of the photocurrent due to the increase.

<Experimental Example 4>

In order to confirm the photoelectric conversion efficiency of the solar cell according to the present invention, the solar cells prepared in Examples 3 to 5 and Comparative Examples 1 to 4 were irradiated with a power of 100 mW / cm ^-2 using a solar simulator The efficiency was measured under the condition of AM 1.5 of Table 1. The results are shown in Table 1. The current density-voltage curves (JV curves) of the solar cells manufactured in Examples 3 to 5 and Comparative Examples 1 to 3 are shown in Fig. 6 (a).

Solar cell
Nanoparticle Nanoparticle content [wt.%] Open-circuit voltage
(V _oc ) [V] Short circuit current density
(J _sc ) [mA / cm ² ] Fill factor
(FF) [%] Photoelectric conversion efficiency (PCE) [%] Comparative Example 1 - - 0.61 9.05 65 3.61 Comparative Example 2 Ag One 0.61 9.1 65 3.66 Comparative Example 3 Ag-SiO ₂ One 0.61 9.61 65 3.86 Example 3 Ag-SiO ₂ -ZnO 0.5 0.61 10.27 65 4.12 Example 4 Ag-SiO ₂ -ZnO One 0.61 10.55 65 4.28 Example 5 Ag-SiO ₂ -ZnO 2 0.61 10.2 64 4.06 Comparative Example 4 Ag-SiO ₂ -ZnO 3 0.61 9.65 65 3.89

As shown in Table 1, the solar cells of Comparative Examples 1 to 3, which did not contain the triple core shell nanoparticles, exhibited a photoelectric conversion efficiency of about 3%.

In addition, by varying the amount of the triple core-shell nanoparticles (0.5, 1 and 3% by weight) of solar cells by forming an electron transport layer in Example 3-5 is increased danryak current density (J _sc) in due 4% high photoelectric conversion Efficiency. However, the solar cell of Comparative Example 4 having a triple-core-shell nanoparticle content of 3 wt% showed an efficiency of 3.89%.

As shown in Table 1 above, it can be seen that an improved general current density and photoelectric conversion efficiency are obtained by including the triple core shell, and it is understood that the content of the triple core shell nanoparticles is preferably 0.5 to 2 wt% have.

When the content of the triple core shell nanoparticles is out of the above range, the efficiency of the solar cell is lowered due to the decrease of the surface resonance effect or the increase of the surface roughness.

The external quantum efficiecy (EQE) curves of the solar cells prepared in Comparative Examples 1 to 3 and Examples 3 to 5 are shown in Fig. 6 (b), and the solar cells of Examples 3 to 5 are shown in Comparative Examples It can be confirmed that the solar cell has higher external photon efficiency than the solar cell of 1 to 3.

As a result, it can be seen that the electron current transporting layer including the triple core shell improves the current density. By forming the semiconductor shell on the plasmon particle, the charge transport ability of the metal nanoparticles can be improved without reducing the surface plasmon resonance (SPR) As a result, it can be seen that a high photoelectric conversion efficiency of the solar cell is obtained.

Claims (22)

Metal nanoparticle cores;
A dielectric shell surrounding the metal nanoparticles; And
And a semiconductor shell surrounding the dielectric shell.
The method of claim 1, wherein the metal nanoparticles are at least one selected from the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), platinum (Pt) Containing triple core shell nanoparticles.
The method of claim 1, wherein the dielectric is selected from the group consisting of silicon oxide, titanium oxide, zirconium oxide, strontium oxide, lanthanum oxide, vanadium oxide, molybdenum oxide, Mo) oxide, tungsten (W) oxide, niobium oxide, magnesium oxide, aluminum oxide, yttrium oxide, scandium oxide, (SrTi) oxide, wherein the triple-core-shell nanoparticle is one or more kinds of dielectric oxides.
The semiconductor according to claim 1, wherein the semiconductor is at least one semiconductor oxide selected from the group consisting of zinc (Zn) oxide, gallium (Ga) oxide, indium (In) oxide, tin (Sn) oxide, and titanium &Lt; / RTI &gt;
The triple core shell nanoparticle according to claim 1, wherein the metal nanoparticles are silver nanoparticles, the dielectric shell is a silicon oxide shell, and the semiconductor shell is zinc oxide.
The triple core shell nanoparticle according to claim 1, wherein the size of the triple core shell particle is 30 to 70 nm.
Preparing metal core nanoparticles (step 1);
Forming a dielectric shell on the surface of the metal nanoparticle core of step 1 (step 2); And
And forming a semiconductor shell on the metal-dielectric core shell surface of step 2 (step 3).
The method of claim 7, wherein the metal nanoparticles of step 1 are formed from one metal precursor selected from the group consisting of gold, silver, copper and aluminum, platinum, palladium, nickel and iron. A method for producing shell nanoparticles.
The method of claim 8, wherein the precursor is _{AgBF 4, AgCF 3 SO 3,} AgClO 4, AgNO 2, AgNO 3, Ag (CH 3 COO), AgPF 6 and Ag (CF ₃ COO) 1 selected from the group consisting of Wherein the core-shell nanoparticles are seeds.
8. The method of claim 7, wherein the dielectric of step ( ₂ ) is silicon oxide (SiO2).
The method of claim 10, wherein the silicon oxide precursor is selected from the group consisting of tetramethylorthosilicate, tetraacetoxysilane, tetraethylorthosilicate, tetramethoxysilane, tetrapropoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, phenyl Wherein the triethoxysilane is one selected from the group consisting of trimethoxysilane, methyltriethoxysilane, methyl acetoxysilane, phenyltrimethoxysilane, and ethyltriethoxysilane.
8. The method of claim 7, wherein in step 3, the semiconductor is at least one semiconductor oxide selected from the group consisting of zinc oxide, gallium oxide, indium oxide, tin oxide, and titanium oxide. Way.
13. The method of claim 12, wherein the precursor of zinc oxide is selected from the group consisting of zinc citrate dihydrate, zinc acetate, zinc acetate dihydrate, zinc acetylacetonate hydrate, Zinc acrylate, Zinc chloride, Zinc fluoride, Zinc diethyldithiocarbamate, Zinc dimethyldithiocarbamate, zinc fl uoride, zinc fluoride, Zinc fluoride hydrate, Zinc hexafluoroacetylacetonate dihydrate, Zinc methacrylate, Zinc nitrate hexahydrate, Zinc nitrate hydrate (Zinc nitrate hydrate), Zinc nitrate hydrate ) And zinc perchlorate hexahydrate Zirconium hexahydrate, and zinc perchlorate hexahydrate. 2. The method of claim 1,
Board; cathode; An electron transport layer; A photoactive layer; A hole transport layer; And a positive electrode,
Wherein the electron transporting layer comprises the triple-core-shell nanoparticles and the semiconductor oxide nanoparticles of claim 1.
15. The method of claim 14, wherein the semiconductor oxide nanoparticles are formed from one or more semiconductor oxides selected from the group consisting of zinc oxide, gallium oxide, indium oxide, tin oxide, and titanium oxide.
Forming a cathode layer on the substrate (Step 1);
A step (step 2) of forming an electron transporting layer containing triple core shell nanoparticles and semiconductor oxide nanoparticles;
Forming a photoactive layer (step 3);
Forming a hole transporting layer (step 4); And
And forming a positive electrode layer (Step 5).
15. The method of claim 14,
The electron transport layer of step 2
Preparing triple core shell nanoparticles (step A);
Producing semiconductor oxide nanoparticles (step B);
Preparing a mixed solution of triple core shell particles and semiconductor nanoparticles (step C); And
And coating the mixed solution of the step C on the cathode layer (step D).
18. The method of manufacturing a solar cell according to claim 17, wherein the mixed solution in step C is prepared by adding 0.5 to 2% by weight of triple-core-shell nanoparticles to the mass of semiconductor oxide nanoparticles.
15. The method of claim 14, wherein the cathode layer is tin-doped indium oxide (ITO: tin-doped indium oxide ), tin fluorine-doped oxide (FTO, fluorine-doped tin oxide ), ZnO-Ga 2 O 3, ZnO-Al 2 O ₃ , and SnO ₂ -Sb ₂ O ₃ .
15. The method of claim 14, wherein the photoactive layer is selected from the group consisting of [6,6] -phenyl-C60 butyric acid methyl ester (PCBM), poly [2-methoxy-5- (2'-ethylhexyloxy) PPV), poly (3-hexylthiophene (P3HT) and poly [N-9 "-hepta-decanyl-2,7-carbazole- , 1 ', 3'-benzothiadiazole)] (PCDTBT).
15. The method of claim 14 wherein the hole transport layer is a molybdenum trioxide (MoO _3), chromium oxide (CrO _X ), Vanadium pentoxide (V ₂ O ₅ ), and nickel oxide (NiO).
15. The method of manufacturing a solar cell according to claim 14, wherein the anode layer is one selected from the group consisting of silver (Ag), gold (Au), and nickel (Ni)

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