CN106549106A - A kind of thin-film solar cells based on laminated perovskite structure material and preparation method thereof - Google Patents

Abstract

The invention provides a thin-film solar cell based on a layered perovskite structure material, comprising a substrate, a hole transport layer, a light absorption layer, an electron transport layer and an electrode connected in sequence, wherein the substrate is indium tin oxide Conductive glass; the hole transport layer is poly 3,4-ethylenedioxythiophene/polystyrene sulfonate; the light absorbing layer is a layered perovskite material (C ₂ H ₉ N ₂ ) (CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ or (C ₂ H ₉ N ₂ )(NH ₂ CH=NH ₂ ) ₂ Pb ₃ I ₁₀ ; the electron transport layer is a fullerene derivative; the electrode is an aluminum film. The invention also provides a method for preparing a thin-film solar cell based on the layered perovskite structure material. The thin film solar cell of the invention adopts the layered perovskite structure material as the light absorption layer, which can improve the stability of the thin film solar cell.

Description

A kind of thin-film solar cell based on layered perovskite structure material and its preparation method

technical field

The invention relates to a solar cell, and more particularly to a thin-film solar cell based on a layered perovskite structure material and a preparation method thereof.

Background technique

Solar energy is the most important source of human energy on the earth's surface. Since the formation speed of ore energy is much lower than its mining speed, mining difficulty and cost are getting higher and higher. The energy return rate of ore energy, that is, the ratio of the amount of energy obtained through energy mining to the amount of energy consumed in the mining process, has long-term Since then, it has been on a downward trend, and as the rate of return declines further, it will not make economic sense to mine ore energy. It is predicted that with the current growth rate of energy consumption, by 2050 and 2100, the global energy consumption will only be provided by solar power generation. With the gradual maturity of solar technology, the unit cost has been decreasing, and the return on energy investment has gradually increased. The penetration rate of solar power generation is also increasing exponentially. Perovskite solar cells are a new type of thin-film solar cells, which mainly use photovoltaic materials with a perovskite structure to achieve photoelectric conversion. ) certified highest photoelectric conversion efficiency has reached 22%, with a wide range of application prospects.

However, due to the poor stability of the currently used light-absorbing layer materials in the air, the prepared thin-film solar cells have poor stability in the air and cannot be industrialized. In addition, the light-absorbing layer thin films of planar cells The preparation process of the solar cell is complex, and it is difficult to prepare a light-absorbing layer film with a dense surface, which greatly limits the improvement of the photoelectric conversion efficiency of solar cells. Therefore, the use of layered perovskite structure materials with better stability as the light-absorbing layer of thin-film solar cells is of great significance for promoting the practical application of perovskite solar cells.

Contents of the invention

The object of the present invention is to provide a thin-film solar cell based on a layered perovskite structure material and a preparation method thereof, so as to solve the problem of poor stability of the light-absorbing layer material in the prior art in the air.

The thin-film solar cell based on the layered perovskite structure material provided by the present invention includes a substrate, a hole transport layer, a light absorption layer, an electron transport layer and an electrode connected in sequence, wherein the substrate is an indium tin oxide conductive glass (ITO); the hole transport layer is poly 3,4-ethylenedioxythiophene/polystyrene sulfonate (PEDOT:PSS); the light absorption layer is a layered perovskite material (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ or (C ₂ H ₉ N ₂ )(NH ₂ CH=NH ₂ ) ₂ Pb ₃ I ₁₀ ; the electron transport layer is a fullerene derivative (PCBM); The electrodes are aluminum thin films.

Preferably, the thickness of the light absorbing layer is 60-300 nm.

Preferably, the indium tin oxide conductive glass (ITO) is treated indium tin oxide conductive glass (ITO). The treatment process is that the ITO conductive glass is ultrasonically cleaned with acetone, ethanol and deionized water successively, and then treated with ultraviolet and ozone. The power of ultrasonic cleaning is 30W, the frequency is 40KHZ, and the cleaning time is 20-30min; the ultraviolet and ozone treatment time is 30-60min to obtain clean indium tin oxide conductive glass.

Preferably, the hole transport layer has a thickness of 20-500 nm.

Preferably, the molecular formula of the electron transport layer is C ₈₂ H ₁₄ O ₂ or C ₇₂ H ₁₄ O ₂ .

Preferably, the electrode has a thickness of 50-80 nm.

The present invention also provides a method for preparing a thin-film solar cell based on a layered perovskite structure material, comprising the following steps: S1, providing a substrate of indium tin oxide conductive glass (ITO); S2, forming a A hole-transport layer of poly-3,4-ethylenedioxythiophene/polystyrenesulfonate (PEDOT:PSS); S3, a light-absorbing layer of layered perovskite material is formed on top of the hole-transport layer, so The layered perovskite material is (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ or (C ₂ H ₉ N ₂ )(NH ₂ CH=NH ₂ ) ₂ Pb ₃ I ₁₀ ; S4, forming an electron transport layer of a fullerene derivative (PCBM) on the light absorbing layer; S5, forming an electrode of an aluminum thin film on the electron transport layer.

Preferably, step S1 includes ultrasonically cleaning the indium tin oxide conductive glass (ITO) with acetone, ethanol, and deionized water in sequence, and then treating it with ultraviolet and ozone to form a substrate.

Preferably, step S2 includes spin-coating a precursor solution of poly-3,4-ethylenedioxythiophene/polystyrene sulfonate (PEDOT:PSS) on the substrate, and annealing to form a hole transport layer.

Preferably, step S3 includes spin-coating the precursor solution of the layered perovskite material onto the hole transport layer, and annealing to form the light absorbing layer.

Preferably, the preparation process of the precursor solution of the layered perovskite material includes: S31, synthesize (C ₂ H ₉ N ₂ )I ₂ crystals by hydroiodic acid and ethylenediamine; S32, synthesize (C ₂ Precursors of layered perovskite materials (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ obtained by dissolving H ₉ N ₂ )I ₂ , CH ₃ NH ₃ I and PbI ₂ in organic solvents solution; or dissolve (C ₂ H ₉ N ₂ )I ₂ , NH ₂ CH=NH ₂ I and PbI ₂ in an organic solvent to obtain a layered perovskite material (C ₂ H ₉ N ₂ )(NH ₂ CH= NH ₂ ) ₂ Pb ₃ I ₁₀ precursor solution.

Preferably, step S4 includes spin-coating a solution of fullerene derivatives (PCBM) on the light-absorbing layer to form an electron-transporting layer.

Preferably, step S5 includes heating, melting, evaporating and depositing aluminum on the electron transport layer to form an electrode.

The invention adopts the layered perovskite structure material as the light absorbing layer, which can improve the stability of the thin-film solar cell, prolong the service life of the cell, and reduce the preparation cost. The beneficial effect of the present invention is that: the layered perovskite material (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ or (C ₂ H ₉ N ₂ )(NH ₂ CH The layers of =NH ₂ ) ₂ Pb ₃ I ₁₀ are closely bonded, regular in shape and uniform in size. The sheets tightly bonded to the surface are similar to a "protective cover", which can play a protective role and reduce the contact between the internal perovskite structure material and the moisture in the air, so that it can exist stably in a humid environment. Layered perovskite materials are used in thin-film solar cells, which can effectively improve the film-forming quality and stability of the light-absorbing layer, and can reduce the influence of water vapor in the air on the stability of the device, prolonging the service life of the battery; at the same time, it can regulate the interface It can achieve better energy level matching, the energy conversion efficiency can reach 11.58%, and the repeatability is very good, which makes the industrialization of perovskite solar cells possible.

detailed description

The preparation method of the thin film solar cell according to the present invention first includes the preparation of layered perovskite material (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ , the specific process is as follows:

1. Synthesis of (C ₂ H ₉ N ₂ )I ₂ : in a water bath at 0°C, slowly add 57wt.% hydroiodic acid aqueous solution to 99wt.% ethylenediamine dropwise with a pipette, wherein hydroiodic acid and The molar ratio of ethylenediamine is 1:0.6-0.8, magnetically stirred for 6h, and the mixed solution is subjected to rotary evaporation at 80-90°C for 0.2-1h. After the liquid is evaporated to dryness, it is cooled to room temperature and filtered to obtain yellow-white crystals. , the white crystals were placed in a positive air drying oven at 40-80° C. for 3-6 hours in vacuum to obtain (C ₂ H ₉ N ₂ )I ₂ crystals.

Both CH ₃ NH ₃ I and PbI ₂ were purchased from Shanghai Maxway Technology Co., Ltd.

2. Synthesis of (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ : (C ₂ H ₉ N ₂ ) I ₂ , CH ₃ NH ₃ I and PbI ₂ according to the ratio of 1:2:3 Proportions were dissolved in N,N-dimethylformamide solution, stirred at room temperature for 15 minutes, and kept at 50-70°C for 3-5 hours to obtain a layered perovskite material (C ₂ H ₉ N ₂ ) (CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ precursor solution.

Alternatively, the preparation method of the thin-film solar cell according to the present invention first includes the preparation of the layered perovskite material (C ₂ H ₉ N ₂ )(NH ₂ CH=NH ₂ ) ₂ Pb ₃ I ₁₀ , and the specific process is as follows:

1. Synthesis of (C ₂ H ₉ N ₂ )I ₂ : in a water bath at 0°C, slowly add 57wt.% hydroiodic acid aqueous solution to 99wt.% ethylenediamine dropwise with a pipette, wherein hydroiodic acid and The molar ratio of ethylenediamine is 1:0.6-0.8, magnetically stirred for 6h, and the mixed solution is subjected to rotary evaporation at 80-90°C for 0.2-1h. After the liquid is evaporated to dryness, it is cooled to room temperature and filtered to obtain yellow-white crystals. , the white crystals were placed in a positive air drying oven at 40-80° C. for 3-6 hours in vacuum to obtain (C ₂ H ₉ N ₂ )I ₂ crystals.

Both NH ₂ CH=NH ₂ I and PbI ₂ were purchased from Shanghai Maxway Technology Co., Ltd.

2. Synthesis of (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb ₃ I ₁₀ : (C ₂ H ₉ N ₂ ) I ₂ , NH ₂ CH=NH ₂ I and PbI ₂ according to 1:2: The ratio of 3 was dissolved in N,N-dimethylformamide solution, stirred at room temperature for 15 minutes, and kept at 50-70°C for 3-5 hours to obtain a layered perovskite material (C ₂ H ₉ N ₂ ) (NH ₂ CH=NH ₂ ) ₂ Pb ₃ I ₁₀ precursor solution.

The preparation method of the thin film solar cell of the present invention will be further described below in conjunction with specific examples. It should be understood that the following examples are only used to illustrate the present invention but not to limit the scope of the present invention.

Example 1

A method for preparing a thin-film solar cell based on a layered perovskite structure material, comprising the steps of:

Step S1: Provide a substrate: ultrasonically clean indium tin oxide conductive glass (ITO) with acetone, ethanol, and deionized water in sequence, and then treat with ultraviolet and ozone. The power of ultrasonic cleaning is 30W, the frequency is 40KHZ, and the cleaning time is 20min; UV ozone treatment time is 30min, to obtain clean indium tin oxide conductive glass (ITO);

Step S2, forming a hole transport layer on the substrate obtained in S1: Spin-coat the prepared PEDOT:PSS precursor solution onto indium tin oxide conductive glass (ITO) at a speed of 5000r/s for 20s, and then , annealing at 500°C for 1 hour to form a hole transport layer;

Step S3, forming a layered perovskite light absorption layer on the hole transport layer obtained in S2: layered perovskite structure material (C ₂ H ₉ N ₂ )(CH ₃ NH ₃ ) ₂ Pb _{3 The} precursor solution of I10 is spin-coated on the top of PEDOT:PSS, the rotating speed is 3000r/s, the time is 60s, and then, annealed at 100°C for 10 minutes to form a light-absorbing layer;

Step S4, forming an electron transport layer on the light absorbing layer prepared in S3: spin-coat the configured PCBM solution on the light absorbing layer at a rotation speed of 3000r/s for 35s to form an electron transport layer;

Step S5, forming an electrode on the electron transport layer prepared in S4: the thermal evaporation method is as follows: at a vacuum degree of 2.5×10-4 Pa, an aluminum electrode is deposited on the electron transport layer by thermal evaporation with a thickness of 60 nm.

The thin film solar cell prepared in this embodiment has an open circuit voltage of 1.24V, a short circuit current density of 16.57mA/cm2, a fill factor of 0.563, and an energy conversion efficiency of 11.58%.

Example 2

A method for preparing a thin-film solar cell based on a layered perovskite structure material, comprising the steps of:

Step S1: Provide a substrate: ultrasonically clean indium tin oxide conductive glass (ITO) with acetone, ethanol, and deionized water in sequence, and then treat with ultraviolet and ozone. The power of ultrasonic cleaning is 30W, the frequency is 40KHZ, and the cleaning time is 30min; ultraviolet ozone treatment time is 60min, to obtain clean indium tin oxide conductive glass (ITO);

Step S2, forming a hole transport layer on the substrate obtained in S1: Spin-coat the prepared PEDOT:PSS precursor solution onto indium tin oxide conductive glass (ITO) at a speed of 5000r/s for 20s, and then , annealing at 500°C for 1 hour to form a hole transport layer;

Step S3, forming a layered perovskite light absorption layer on the hole transport layer obtained in S2: layered perovskite structure material (C ₂ H ₉ N ₂ )(NH ₂ CH=NH2) ₂ Pb The precursor solution of ₃ I ₁₀ was spin-coated on the top of PEDOT:PSS at a rotation speed of 3000r/s for 60s, and then annealed at 100°C for 10 minutes to form a light-absorbing layer;

Step S4, forming an electron transport layer on the light absorbing layer prepared in S3: spin-coat the configured PCBM solution on the light absorbing layer at a rotation speed of 3000r/s for 35s to form an electron transport layer;

Step S5, forming an electrode on the electron transport layer prepared in S4: the thermal evaporation method step is: under a vacuum degree of 2.5×10-4Pa, use thermal evaporation to evaporate an aluminum electrode on the electron transport layer with a thickness of 80nm.

The thin film solar cell prepared in this embodiment has an open circuit voltage of 0.95V, a short circuit current density of 15.53mA/cm2, a fill factor of 0.611, and an energy conversion efficiency of 8.98%.

Example 3

A method for preparing a thin-film solar cell based on a layered perovskite structure material, comprising the steps of:

Step S1: Provide a substrate: ultrasonically clean indium tin oxide conductive glass (ITO) with acetone, ethanol, and deionized water in sequence, and then treat with ultraviolet and ozone. The power of ultrasonic cleaning is 30W, the frequency is 40KHZ, and the cleaning time is 25min; UV ozone treatment time is 35min, to obtain clean indium tin oxide conductive glass (ITO);

Step S2, forming a hole transport layer on the substrate obtained in S1: Spin-coat the prepared PEDOT:PSS precursor solution onto indium tin oxide conductive glass (ITO) at a speed of 5000r/s for 20s, and then , annealing at 500°C for 1 hour to form a hole transport layer;

Step S3, forming a layered perovskite light absorption layer on the hole transport layer obtained in S2: layered perovskite structure material (C ₂ H ₈ N ₁₀ H ₃ )(CH ₃ NH ₃ ) ₂ The precursor solution of Pb ₃ I ₁₀ was spin-coated on top of PEDOT:PSS at a rotation speed of 3000r/s for 60s, and then annealed at 100°C for 10 minutes to form a light-absorbing layer;

Step S4, forming an electron transport layer on the light absorbing layer prepared in S3: spin-coat the configured PCBM solution on the light absorbing layer at a rotation speed of 3000r/s for 35s to form an electron transport layer;

Step S5, forming an electrode on the electron transport layer prepared in S4: the thermal evaporation method is as follows: at a vacuum degree of 2.5×10-4 Pa, an aluminum electrode is deposited on the electron transport layer by thermal evaporation with a thickness of 60 nm.

The thin film solar cell prepared in this example has an open circuit voltage of 0.96V, a short circuit current density of 16.55mA/cm2, a fill factor of 0.627, and an energy conversion efficiency of 9.79%.

Example 4

A method for preparing a thin-film solar cell based on a layered perovskite structure material, comprising the steps of:

Step S1: Provide a substrate: ultrasonically clean indium tin oxide conductive glass (ITO) with acetone, ethanol, and deionized water in sequence, and then treat with ultraviolet and ozone. The power of ultrasonic cleaning is 30W, the frequency is 40KHZ, and the cleaning time is 20min; UV ozone treatment time is 40min, to obtain clean indium tin oxide conductive glass (ITO);

Step S2, forming a hole transport layer on the substrate obtained in S1: Spin-coat the prepared PEDOT:PSS precursor solution onto indium tin oxide conductive glass (ITO) at a speed of 5000r/s for 20s, and then , annealing at 500°C for 1 hour to form a hole transport layer;

Step S3, forming a layered perovskite light absorption layer on the hole transport layer obtained in S2: layered perovskite structure material (C ₂ H ₈ N ₁₀ H ₃ )(CH ₃ NH ₃ ) ₂ The precursor solution of Pb ₃ I ₁₀ was spin-coated on top of PEDOT:PSS at a rotation speed of 3000r/s for 60s, and then annealed at 100°C for 10 minutes to form a light-absorbing layer;

Step S4, forming an electron transport layer on the light absorbing layer prepared in S3: spin-coat the configured PCBM solution on the light absorbing layer at a rotation speed of 3000r/s for 35s to form an electron transport layer;

Step S5, forming an electrode on the electron transport layer prepared in S4: the thermal evaporation method is as follows: under a vacuum degree of 2.5×10-4Pa, use thermal evaporation to evaporate an aluminum electrode on the electron transport layer with a thickness of 50nm.

The thin film solar cell prepared in this embodiment has an open circuit voltage of 0.94V, a short circuit current density of 18.55mA/cm2, a fill factor of 0.635, and an energy conversion efficiency of 10.91%.

What is described above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Various changes can also be made to the above embodiments of the present invention. That is to say, all simple and equivalent changes and modifications made according to the claims and description of the application for the present invention fall within the protection scope of the claims of the patent of the present invention. What is not described in detail in the present invention is conventional technical content.

Claims (13)

1. a kind of thin-film solar cells based on laminated perovskite structure material, including the substrate, hole transport that are sequentially connected Layer, light absorbing zone, electron transfer layer and electrode, it is characterised in that the substrate is indium tin oxide-coated glass；Hole transmission layer For poly- 3,4-ethylene dioxythiophene/poly styrene sulfonate；The light absorbing zone is layered perovskites (C₂H₉N₂) (CH₃NH₃)₂Pb₃I₁₀Or (C₂H₉N₂)(NH₂CH=NH₂)₂Pb₃I₁₀；Electron transfer layer is fullerene derivate；The electrode is aluminum Thin film.

2. thin-film solar cells according to claim 1, it is characterised in that the thickness of the light absorbing zone is 60- 300nm。

3. thin-film solar cells according to claim 1, it is characterised in that the indium tin oxide-coated glass was to process Indium tin oxide-coated glass.

4. thin-film solar cells according to claim 1, it is characterised in that the thickness of the hole transmission layer is 20- 500nm。

5. thin-film solar cells according to claim 1, it is characterised in that the molecular formula of electron transfer layer is C₈₂H₁₄O₂ Or C₇₂H₁₄O₂。

6. thin-film solar cells according to claim 1, it is characterised in that the thickness of the electrode is 50-80nm.

7. a kind of preparation method of the thin-film solar cells based on laminated perovskite structure material, it is characterised in that include with Lower step：

S1, there is provided the substrate of indium tin oxide-coated glass；

S2, the over the substrate square hole transmission layer into poly- 3,4-ethylene dioxythiophene/poly styrene sulfonate；

S3, forms the light absorbing zone of layered perovskites in the top of hole transmission layer, and layered perovskite material is (C₂H₉N₂)(CH₃NH₃)₂Pb₃I₁₀Or (C₂H₉N₂)(NH₂CH=NH₂)₂Pb₃I₁₀；

S4, forms the electron transfer layer of fullerene derivate above the light absorbing zone；

S5, the on the electron transport layer square electrode into aluminium film.

8. preparation method according to claim 7, it is characterised in that step S1 is included indium tin oxide-coated glass successively It is cleaned by ultrasonic with acetone, ethanol, deionized water, then Jing UV ozones is processed, and form substrate.

9. preparation method according to claim 7, it is characterised in that step S2 include by poly- 3,4-ethylene dioxythiophene/ The precursor solution of poly styrene sulfonate is spun on substrate, and annealing forms hole transmission layer.

10. preparation method according to claim 7, it is characterised in that step S3 is included before layered perovskites Drive liquid solution to be spun on hole transmission layer, annealing forms light absorbing zone.

11. preparation methoies according to claim 10, it is characterised in that the precursor solution of layered perovskite material Preparation technology include：

S31, obtains (C by hydroiodic acid and ethylenediamine synthesis₂H₉N₂)I₂Crystal；

S32, by (C₂H₉N₂)I₂、CH₃NH₃I and PbI₂Layered perovskites (C is obtained in being dissolved in organic solvent₂H₉N₂) (CH₃NH₃)₂Pb₃I₁₀Precursor solution；Or by (C₂H₉N₂)I₂、NH₂CH=NH₂I and PbI₂Obtain in being dissolved in organic solvent Layered perovskites (C₂H₉N₂)(NH₂CH=NH₂)₂Pb₃I₁₀Precursor solution.

12. preparation methoies according to claim 7, it is characterised in that step S4 is included the solution of fullerene derivate It is spun on light absorbing zone, forms electron transfer layer.

13. preparation methoies according to claim 7, it is characterised in that step S5 is included aluminum heating fusing hydatogenesis To on electron transfer layer, electrode is formed.