CN107302034B - Solar cell with surface plasmon enhanced nano microcavity structure - Google Patents

Abstract

A surface plasmon-enhanced nano-microcavity structure solar cell includes a composite three-dimensional nano-microcavity with surface plasmon-enhancing properties and a PIN or NIP type thin-film solar cell. The composite three-dimensional nano-microcavity with surface plasmon enhancement properties is composed of oxide three-dimensional nanostructures and metal nanoparticles; the thin-film solar cells include inorganic thin-film solar cells, organic thin-film solar cells, and at least one of the above two types. tandem solar cells. The beneficial effects of the invention are as follows: the surface plasmon effect of metal nanoparticles is introduced into the three-dimensional nano-microcavity light trapping structure to obtain a nano-microcavity structure with a localized high-energy electric field, so as to enhance the optical path expansion, and improve the photon tailoring and modulation. It can achieve good light trapping effect and optimize charge collection performance. This structure can achieve good effects of improving the effective optical absorption efficiency of the battery and reducing the recombination probability of photogenerated carriers. Synchronized improvement of electrical characteristics.

Description

A surface plasmon-enhanced solar cell with nano-microcavity structure

technical field

The invention belongs to the field of thin film solar cells, in particular to a solar cell with a surface plasmon enhancement type nano-micro cavity structure.

Background technique

In order for solar cells to become the main form of energy in the future, high efficiency and low cost must be achieved, of which thinning has always been one of the most important development trends. In addition, for amorphous silicon thin-film cells, the reduction in the thickness of the active layer is also conducive to reducing the photo-induced degradation effect and improving the stability of the device. For compound solar cells such as copper indium gallium selenide and cadmium telluride, the reduction in thickness can reduce the use of toxic and trace elements, which is also conducive to enhancing industrial competitiveness. However, the thinning of the material, due to its limited absorption coefficient (especially near the band gap), must rely on efficient light management structures to obtain a thick "optical thickness" with a thin "physical thickness" to achieve effective solar photons. absorb.

With the deepening of research on solar cells, people gradually realize the importance of efficient light management structures. In recent years, solar cells based on three-dimensional nano-microcavity structures have received more and more attention due to their excellent performance. The incident photons can achieve multiple scattering at the interface of the three-dimensional nano-microcavity structure, providing multiple incident paths for photons, greatly reducing the binding correlation between the absorption characteristics of the active layer and the incidence angle distribution, and obtaining high absorption performance in a wide spectral range. , see literature: MD Kelzenberg, SW Boettcher, JA Petykiewicz, et al, Nature Mater. 9(2010) 239-44, JY Jung, Z. Guo, SW Jee, et al, A strong antireflectivesolar cell prepared by tapering silicon nanowires, Opt. Express 18 (2010) A286-92. In addition, a large number of free electrons on the surface of nano-scale metal structures can interact with photons to generate continuous shared oscillations, which will form a kind of free electron and photon interaction called surface plasmon polariton (SPP). Mixed excited states with remarkable far-field and near-field optoelectronic properties. On the one hand, using the far-field optical properties of surface plasmons of nano-metal structures, through the far-field coupling with photons, the optical waveguide transmission mode of photons is excited, and good light trapping properties in thin-film solar cells have been obtained. Significant enhancement of the photon absorption of accessories; on the other hand, utilizing the near-field electrical properties of the nano-metal structure, the excited surface plasmons can change the electromagnetic field distribution properties of the surrounding space, thereby obtaining effective regulation of the work function of the electron transport layer in organic solar cells , to achieve efficient charge transport, see literature: HA Atwater, A. Polman Nature Materials 9 (2010) 205-213, S. Trost, T. Becker, K. Zilberberg, et al, Scientific Reports 5 (2015) 7765.

Based on this, the present invention proposes a solar cell with a surface plasmon-enhanced nano-microcavity structure, and proposes to introduce the surface plasmon effect of metal nanoparticles into a three-dimensional nano-microcavity light trapping structure to obtain a localized high-energy electric field. The nano-microcavity structure can enhance the optical path expansion, improve the photon tailoring and modulation effect, obtain a good light trapping effect, and optimize the charge collection performance. The good effect can be applied to various solar cells, which is beneficial to the simultaneous improvement of the optical and electrical properties of the cells.

SUMMARY OF THE INVENTION

The purpose of the present invention is to further improve the performance of solar cells, and propose a solar cell with a surface plasmon enhanced nano-microcavity structure, which introduces the surface plasmon effect of nanoparticles into a three-dimensional nano-microcavity light trapping structure to obtain a localized light-trapping structure. A solar cell with a nano-microcavity structure with a high-energy electric field, this structure can achieve good effects of improving the effective optical absorption efficiency of the cell and reducing the recombination probability of photogenerated carriers, and can be applied to various thin-film solar cells. Synchronized improvement of electrical characteristics.

Technical scheme of the present invention:

A solar cell with a surface plasmon enhancement type nano-microcavity structure, comprising a composite nanostructure with surface plasmon enhancement properties and a PIN or NIP type thin film solar cell, characterized in that: the thin film solar cell is directly deposited A three-dimensional nano-micro-cavity structure is formed on the composite nano-structure; the surface plasmon-enhanced nano-micro-cavity solar cell has a remarkable light absorption enhancement effect.

The composite nanostructure with surface plasmon enhancement properties is composed of oxide three-dimensional nanoarrays and metal nanoparticles, wherein the three-dimensional nanoarrays include at least one of nanopillars, nanocones, and nanosphere arrays, wherein the metal nanoparticles include At least one material among gold nanoparticles, silver nanoparticles, and aluminum nanoparticles.

The composite nanostructure with enhanced surface plasmon properties has conductive properties and can achieve efficient transport of electrons or holes.

The thin film solar cells include inorganic thin film solar cells, organic thin film solar cells and stacked solar cells composed of at least one of the above two.

【Description of drawings】

FIG. 1 is a schematic diagram of the structure of a surface plasmon-enhanced nano-microcavity solar cell.

FIG. 2 is a test curve of external quantum efficiency of a surface plasmon-enhanced nano-microcavity structure amorphous silicon thin film solar cell in Example 1. FIG.

【Detailed ways】

Embodiment 1:

A solar cell with a surface plasmon-enhanced nano-microcavity structure, the structure is as follows:

1) A layer of monodisperse SiO ₂ spheres with a particle size of 300 nm was prepared on a transparent glass substrate, and nano-Ag particles with a particle size of 20 nm were attached on the SiO ₂ spheres, and then a layer of thickness was deposited The transparent conductive ZnO:Al of 500 nm is used as the front electrode, which makes the sheet resistance of the overall structure reach 15 Ω/□. The above three materials constitute a surface plasmon-enhanced composite nanostructure.

2) The p/i/n-type a-Si:H materials were sequentially deposited on the SiO ₂ NS/Ag NPs/ZnO:Al composite nanostructure to form a PIN-type amorphous silicon thin-film solar cell with a thickness of 15 nm / 250 nm, respectively. nm / 15 nm.

3) Fabrication of ZnO/Ag back electrode on top of n-type a-Si:H.

The application results show that compared with the amorphous silicon thin-film solar cells with only planar ZnO:Al front electrodes, the surface plasmon-enhanced nano-microcavity structured amorphous silicon thin-film solar cells can integrate current in the wavelength range from 350 nm to 800 nm by From 11.64 mA/cm ² to 14.07 mA/cm ² , the external quantum efficiency is increased by 20.87%, and it has obvious enhancement effects of light absorption and carrier collection.

The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Substitutions should be covered within the protection scope of the present invention.

Claims (3)

1. a solar cell with a surface plasmon enhanced nano-microcavity structure, comprising a composite nanostructure with surface plasmon enhanced properties and a PIN or NIP type thin-film solar cell, characterized in that: the thin-film solar cell It is directly deposited on the composite nanostructure to form a three-dimensional nano-microcavity structure; the solar cell of the surface plasmon enhanced nano-microcavity has a significant light absorption enhancement effect; the composite nanostructure is composed of oxide three-dimensional nanoarrays and metal nanometers. The particle composition, wherein the three-dimensional nano-array includes at least one of nano-pillars, nano-cones, and nano-sphere arrays, wherein the metal nanoparticles include at least one material among gold nanoparticles, silver nanoparticles, and aluminum nanoparticles; the preparation method is: A layer of monodisperse _SiO2 pellets was prepared on a transparent glass substrate, and nano Ag particles were attached on the _SiO2 pellets, and then a layer of transparent conductive ZnO:Al was deposited as the front electrode to form a surface plasmon-enhanced _SiO2 NS/Ag NPs/ZnO:Al composite nanostructure, p/i/n type functional thin film materials are sequentially deposited on the SiO ₂ NS/Ag NPs/ZnO:Al composite nanostructure to form a PIN type amorphous silicon thin film solar cell, The ZnO/Ag back electrode was fabricated on the n-type functional layer. 2. The solar cell of claim 1, wherein the composite nanostructure with surface plasmon enhancement properties has electrical conductivity and can realize the effective transport of electrons or holes . 3. The solar cell with a surface plasmon enhanced nano-microcavity structure according to claim 1, wherein the thin film solar cell comprises an inorganic thin film solar cell, an organic thin film solar cell and a solar cell composed of at least one of the above two. Laminated solar cells.

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