A method for post-sulfurization of antimony selenide sulfide film, antimony selenide sulfide film obtained, and application thereof

Abstract

The present invention belongs to the technical field of antimony selenide sulfide nanomaterials, and discloses a method for post-sulfurization of an antimony selenide sulfide film, the antimony selenide sulfide film obtained, and its application. The method of the present invention comprises: placing a sodium sulfide solution and an antimony selenide sulfide film in the same closed environment, placing the antimony selenide sulfide film on a support structure, with the antimony selenide sulfide film located above the sodium sulfide solution and not in contact with the sodium sulfide solution, heating the closed environment, performing steam treatment, washing, and drying to obtain a post-sulfurized antimony selenide sulfide film; the antimony selenide sulfide film is prepared by a hydrothermal method. The method of the present invention is safe and non-toxic, has low raw material costs, a low reaction temperature, and a simple operating process. It reduces the generation of sulfur vacancies inside the film, improves the photoelectric performance of the antimony selenide sulfide film, and assembles the sulfurized antimony selenide sulfide film into a solar cell, with a photoelectric conversion efficiency of up to 9.16%.

Description

Technical Field

[0001] The present invention relates to the technical field of antimony selenide sulfide nanomaterials, in particular to a method for post-sulfurization of an antimony selenide sulfide film, the prepared antimony selenide sulfide film and its application. Background Art

[0002] Antimony-based chalcogenide semiconductor materials have the advantages of abundant element reserves and being non-toxic and harmless. As an important member of antimony-based chalcogenide semiconductor materials, antimony selenide sulfide (Sb2(S,Se)3) has an adjustable band gap width (1.1-1.7eV) and a high absorption coefficient in the visible light range (>10 5 cm -1 ), which has attracted extensive attention from researchers in recent years.

[0003] There are many methods for preparing antimony selenide sulfide thin films, including physical and chemical methods. The physical methods mainly include thermal evaporation, magnetron sputtering, and near-space sublimation, but the equipment required for physical methods is generally more expensive. Chemical methods include solution methods, chemical water bath deposition methods, hydrothermal methods, etc. These methods are low-cost and simple to operate, and are widely used preparation methods. At present, the photoelectric conversion efficiency of antimony selenide sulfide thin film solar cells prepared by the hydrothermal method has reached 10.7%. However, the antimony selenide sulfide thin film prepared by the hydrothermal method contains a large number of sulfur vacancies. The loss of sulfur inside the film will produce a large number of defects, resulting in a decrease in the photoelectric conversion efficiency. How to reduce sulfur vacancies and improve the photoelectric performance of antimony selenide is an important issue in promoting the development of antimony selenide sulfide films. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for post-sulfurization of antimony selenide sulfide thin films, the antimony selenide sulfide thin films prepared by the hydrothermal method, and their applications, so as to solve the problem that antimony selenide sulfide thin films prepared by the hydrothermal method contain a large number of sulfur vacancy defects, which leads to a significant reduction in photoelectric conversion efficiency.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for post-sulfurization of an antimony selenide sulfide film, comprising the following steps:

[0007] placing a sodium sulfide solution and an antimony selenide sulfide film in the same closed environment, placing the antimony selenide sulfide film on a support structure so that the antimony selenide sulfide film is above the sodium sulfide solution and does not contact the sodium sulfide solution, heating the closed environment, performing steam treatment, and then washing and drying to obtain a post-sulfurized antimony selenide sulfide film;

[0008] Wherein, the antimony selenide sulfide film is prepared by a hydrothermal method.

[0009] Furthermore, in the method for post-sulfurization of antimony selenide sulfide film, the mass concentration of sodium sulfide in the sodium sulfide solution is 15 to 50 mg / mL.

[0010] Furthermore, in the method for post-sulfurization of the antimony selenide sulfide film, the heating rate is 4-10° C. / min, the steam treatment temperature is 100-180° C., and the steam treatment time is 60-300 min.

[0011] Furthermore, in the method for post-sulfurization of the antimony selenide sulfide film, the washing method is to use water and ethanol to clean respectively, and the drying method is to use N2 to blow dry.

[0012] Furthermore, in the method for post-sulfurization of the antimony selenide sulfide film, the specific process of the hydrothermal method is: mixing potassium antimony tartrate, sodium thiosulfate and selenourea, performing a hydrothermal reaction in a closed environment, and drying and annealing to obtain the antimony selenide sulfide film.

[0013] Furthermore, in the method for post-sulfurization of antimony selenide sulfide film, the mass concentration of sodium sulfide in the sodium sulfide solution is 25 mg / mL, the heating rate is 7°C / min, the steam treatment temperature is 140°C, and the steam treatment time is 180 min.

[0014] The present invention also provides an antimony selenide sulfide film prepared by a method of post-sulfurization of the antimony selenide sulfide film.

[0015] The present invention also provides an application of an antimony selenide sulfide thin film in a solar cell device. The solar cell device includes the following structure: a cathode, an electron transport layer, a light absorption layer, a hole transport layer, and an anode. The light absorption layer in the solar cell device is the antimony selenide sulfide thin film.

[0016] It can be seen from the above technical solutions that compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention utilizes a post-sulfurization process to treat an antimony selenide sulfide thin film prepared by a hydrothermal method, thereby reducing the generation of sulfur vacancies within the film and improving the photoelectric performance of the antimony selenide sulfide film. When the sulfurized antimony selenide sulfide film is assembled into a solar cell, the photoelectric conversion efficiency can reach 9.16%. The sulfurization method provided by the present invention is safe and non-toxic, has low raw material costs, a low reaction temperature, and a simple operating process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments or the prior art.

[0019] Figure 1This is a diagram showing the positional relationship between the sodium sulfide solution and the antimony selenide sulfide film in the reactor;

[0020] Figure 2 This is a SEM image of the solar cell device obtained in comparative application example 1;

[0021] Figure 3 This is a SEM image of the solar cell device obtained in Application Example 1;

[0022] Figure 4 This is a SEM image of the solar cell device obtained in Application Example 2;

[0023] Figure 5 This is a SEM image of the solar cell device obtained in Application Example 3;

[0024] Figure 6 The XRD patterns of the solar cell devices obtained in comparative application example 1 and application examples 1 to 3 are shown;

[0025] Figure 7 The current density-voltage curves of the solar cell devices obtained by comparing Application Example 1 and Application Examples 1 to 3 are shown;

[0026] Figure 8 This is a SEM image of the solar cell device obtained in Application Example 4;

[0027] Figure 9 This is a SEM image of the solar cell device obtained in Application Example 5;

[0028] Figure 10 The XRD patterns of the solar cell devices obtained by comparing application examples 1, 2, and 4-5 are shown;

[0029] Figure 11 The current density-voltage curves of the solar cell devices obtained by comparing application examples 1, 2, and 4-5 are shown;

[0030] Figure 12 This is a current density-voltage curve of the solar cell device obtained in Application Example 2. DETAILED DESCRIPTION

[0031] The present invention provides a method for post-sulfurization of an antimony selenide sulfide film, comprising the following steps:

[0032] placing a sodium sulfide solution and an antimony selenide sulfide film in the same closed environment, placing the antimony selenide sulfide film on a support structure so that the antimony selenide sulfide film is above the sodium sulfide solution and does not contact the sodium sulfide solution, heating the closed environment, performing steam treatment, and then washing and drying to obtain a post-sulfurized antimony selenide sulfide film;

[0033] Wherein, the antimony selenide sulfide film is prepared by a hydrothermal method.

[0034] In the present invention, the closed environment is preferably a reactor, and the temperature-raising device is preferably an oven.

[0035] In the present invention, the conditions for placing the sodium sulfide solution and the antimony selenide sulfide film in the same closed environment are preferably: placing the sodium sulfide solution in the reactor liner, and pasting the antimony selenide sulfide film on the support frame and suspending it above the reactor liner, such as Figure 1 shown.

[0036] In the present invention, the mass concentration of sodium sulfide in the sodium sulfide solution is preferably 15 to 50 mg / mL, more preferably 20 to 30 mg / mL, and even more preferably 25 mg / mL. This is because when the sodium sulfide content is low, the sulfurization effect is average; when the sodium sulfide content is too high, the reaction rate is fast and difficult to control.

[0037] In the present invention, the sodium sulfide solution is preferably a sodium sulfide aqueous solution.

[0038] In the present invention, the heating rate is preferably 4 to 10° C. / min, more preferably 6 to 8° C. / min, and even more preferably 7° C. / min.

[0039] In the present invention, the steam treatment temperature is preferably 100-180°C, more preferably 125-165°C, and even more preferably 140°C. The above steam treatment temperatures are selected because, when the temperature is below 100°C, the amount of hydrogen sulfide produced is small and the sulfurization effect is average. When the temperature is above 180°C, it is difficult to operate the oven safely for a long time, and the film surface is severely corroded, which greatly reduces the fill factor of the solar cell device.

[0040] In the present invention, the steam treatment time is preferably 60 to 300 min, more preferably 120 to 200 min, and even more preferably 180 min.

[0041] In the present invention, the washing method is preferably to use water and ethanol for washing respectively.

[0042] In the present invention, the drying method is preferably to use N2 drying.

[0043] In the present invention, the specific process of the hydrothermal method is preferably: potassium antimony tartrate, sodium thiosulfate and selenourea are mixed, a hydrothermal reaction is carried out in a closed environment, and the mixture is dried and annealed to obtain an antimony selenium sulfide film.

[0044] The present invention also provides an antimony selenide sulfide film prepared by a method of post-sulfurization of the antimony selenide sulfide film.

[0045] The present invention also provides an application of an antimony selenide sulfide thin film in a solar cell device, wherein the solar cell device comprises the following structure: a cathode, an electron transport layer, a light absorption layer, a hole transport layer, and an anode, wherein the light absorption layer in the solar cell device is preferably the antimony selenide sulfide thin film.

[0046] The present invention does not limit the cathode, the electron transport layer, the hole transport layer and the anode, and any materials well known to those skilled in the art may be used.

[0047] In the present invention, one option for the cathode is fluorine-doped tin dioxide transparent conductive glass (FTO), one option for the electron transport layer is cadmium sulfide (CdS), one option for the hole transport layer is Spiro-OMeTAD, and one option for the anode is gold. The above materials have no special restrictions on the present invention.

[0048] The present invention does not limit the preparation method of the solar cell device, and a method well known to those skilled in the art can be used.

[0049] One of the methods for preparing the solar cell device of the present invention is preferably:

[0050] (1) FTO pretreatment: FTO was ultrasonically cleaned with glass cleaning agent, ultrapure water, isopropyl alcohol, acetone, and anhydrous ethanol for 30 to 60 minutes respectively, dried with N2, and then cleaned with oxygen ion cleaning agent for 15 minutes;

[0051] (2) Depositing a CdS film on FTO using a chemical water bath method with a film thickness of 50 to 70 nm;

[0052] (3) depositing an antimony selenide sulfide prefilm by a hydrothermal method, and annealing the antimony selenide sulfide prefilm in a nitrogen atmosphere to obtain an antimony selenide sulfide thin film;

[0053] (4) treating the antimony selenide sulfide film by post-sulfurization of the antimony selenide sulfide film;

[0054] (5) After post-sulfurization treatment, Spiro-OMeTAD was spin-coated on the antimony selenide sulfide film at a spin-coating speed of 3000 r / min and a spin-coating time of 30 s;

[0055] (6) Gold electrodes were deposited on Spiro-OMeTAD using thermal evaporation technology with a thickness of 60 to 80 nm.

[0056] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0057] Example 1

[0058] This embodiment provides a method for post-sulfurization of an antimony selenide sulfide film, comprising the following steps:

[0059] 0.3 g of sodium sulfide was mixed with 20 mL of water and placed in a 50 mL reactor liner. The antimony selenide sulfide film was fixed on a support frame and suspended above the sodium sulfide aqueous solution. It was heated to 140 ° C at a rate of 7 ° C / min in a closed environment and kept warm for 180 minutes for steam treatment. The hydrogen sulfide gas generated by the sodium sulfide aqueous solution sulfidized the selenium antimony sulfide film. After the sodium sulfide aqueous solution steam treatment, the antimony selenide sulfide film was rinsed with ultrapure water and ethanol successively, and blown dry with N2 to obtain a post-sulfurized antimony selenide sulfide film.

[0060] Example 2

[0061] This embodiment provides a method for post-sulfurization of antimony selenide sulfide thin films, which differs from Example 1 in that 0.5 g of sodium sulfide is mixed with 20 mL of water and placed in the inner container of a reactor. Other conditions are the same as those in Example 1.

[0062] Example 3

[0063] This embodiment provides a method for post-sulfurization of antimony selenide sulfide thin films, which differs from Example 1 in that 1 g of sodium sulfide is mixed with 20 mL of water and placed in the inner container of a reactor, and other conditions are the same as those in Example 1.

[0064] Example 4

[0065] This embodiment provides a method for post-sulfurization of antimony selenide sulfide thin films, which differs from Example 2 in that: heating is performed to 100° C. at a rate of 5° C. / min in a closed environment, and other conditions are the same as those in Example 2.

[0066] Example 5

[0067] This embodiment provides a method for post-sulfurization of antimony selenide sulfide thin films, which differs from Example 2 in that: heating is performed to 180° C. at a rate of 9.5° C. / min in a closed environment, and other conditions are the same as those in Example 2.

[0068] Comparative Example 1

[0069] This comparative example provides a method for post-treatment of antimony selenide sulfide film, which differs from Example 1 in that: no sodium sulfide is added, 20 mL of water is placed in the inner liner of the reactor, the temperature is lowered to 0°C in a closed environment, and the temperature is kept for 180 minutes. Other conditions are the same as in Example 1.

[0070] Application Examples

[0071] This application example provides a method for preparing a solar cell device, comprising the following steps:

[0072] (1) FTO pretreatment: FTO was ultrasonically cleaned with glass cleaning agent, ultrapure water, isopropyl alcohol, acetone, and anhydrous ethanol for 30 min respectively, dried with N2, and then cleaned with oxygen ion cleaning agent for 15 min;

[0073] (2) CdS thin film was deposited on FTO using a chemical water bath method with a film thickness of 60 nm;

[0074] (3) depositing an antimony selenide sulfide prefilm by a hydrothermal method, and annealing the antimony selenide sulfide prefilm in a nitrogen atmosphere to obtain an antimony selenide sulfide thin film;

[0075] (4) treating the antimony selenide sulfide film by using any of the post-sulfurization or post-treatment methods of Examples 1 to 5 and Comparative Example 1;

[0076] (5) After post-sulfurization treatment, Spiro-OMeTAD was spin-coated on the antimony selenide sulfide film at a spin-coating speed of 3000 r / min and a spin-coating time of 30 s;

[0077] (6) Gold electrodes were deposited on Spiro-OMeTAD using thermal evaporation technology with a thickness of 80 nm.

[0078] The application example of the post-sulfurization method of antimony selenide sulfide film described in Application Example 1 is named Application Example 1, the application example of the post-sulfurization method of antimony selenide sulfide film described in Application Example 2 is named Application Example 2, and so on. The method described in Application Example 3 is Application Example 3, the method described in Application Example 4 is Application Example 4, the method described in Application Example 5 is Application Example 5, and the method described in Comparative Example 1 is Comparative Application Example 1.

[0079] Comparative Example 1: The SEM images of the solar cell devices obtained in Example 1 to Example 3 are as follows: Figures 2 to 5 The obtained XRD pattern is shown in Figure 6 As shown in the figure. The SEM image shows that small holes appear on the surface of the film after sulfurization, which are traces of hydrogen sulfide treatment. When the sodium sulfide content is higher, the surface traces are more serious, and the grain boundaries will be corroded. The XRD image shows that after sodium sulfide treatment, the peak intensity of the film (130) is significantly increased, indicating that the crystallinity of the film is better after sulfurization.

[0080] Comparative Application Example 1, Application Examples 1 to 3 obtained solar cell devices under the illumination of one sun (1.5G) test current density - voltage (JV) curve as shown in FIG Figure 7 As shown, Figure 7 The corresponding photovoltaic parameters are shown in Table 1, where Voc is the open circuit voltage, Jsc is the short circuit current density, FF is the fill factor, and PCE is the conversion efficiency.

[0081] Table 1. Comparison of photovoltaic parameters of solar cell devices obtained in Application Example 1 and Application Examples 1 to 3

[0082]

[0083] Depend on Figure 7 As shown in Table 1, when the sodium sulfide content is 0.5 g, the PCE of the solar cell device is optimal, which is 9.16%.

[0084] Comparative SEM images of solar cell devices obtained in Application Examples 1, 2, 4 and 5 are shown in FIG. Figure 2 、 Figure 4 、 8 The obtained XRD pattern is shown in Figure 9. Figure 10 As shown in the figure, the SEM image shows that the film surface is smooth and well-crystalline after vulcanization. As the vulcanization temperature increases, the film surface exhibits varying degrees of etching. At lower temperatures, small pores appear on the film surface. When the temperature rises to 180°C, etched spots appear on the surface, and the grain boundaries are partially etched away. The XRD pattern shows that the peak intensity of the film increases after vulcanization, and the film has better crystallinity.

[0085] Comparative Application Examples 1, 2, 4-5, and the resulting solar cell devices tested under one solar radiation (1.5G) are shown in the following current density-voltage (JV) curves: Figure 11 As shown, Figure 11 The corresponding photovoltaic parameters are shown in Table 2.

[0086] Table 2. Comparison of photovoltaic parameters of solar cell devices obtained in Application Examples 1, 2, 4-5

[0087]

[0088]

[0089] Depend on Figure 11 As shown in Table 2, when the sulfurization temperature is 140°C, the PCE of the solar cell device is optimal.

[0090] Figure 12Under the optimal post-sulfurization conditions, the JV curve and corresponding photovoltaic parameters of the solar cell device obtained in Example 2 are shown. The open circuit voltage Voc reaches 0.658 V and the short circuit current density Jsc reaches 21.38 mA·cm -2 , the filling factor FF reaches 65.10%, and the conversion efficiency PCE reaches 9.16%.

[0091] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for post-sulfurization of antimony selenide sulfide thin film, characterized in that: The following steps are involved: placing a sodium sulfide solution and an antimony selenide sulfide film in the same closed environment, placing the antimony selenide sulfide film on a support structure so that the antimony selenide sulfide film is above the sodium sulfide solution and does not contact the sodium sulfide solution, heating the closed environment, performing steam treatment, and then washing and drying to obtain a post-sulfurized antimony selenide sulfide film; Wherein, the antimony selenide sulfide film is prepared by a hydrothermal method; The mass concentration of sodium sulfide in the sodium sulfide solution is 15-50 mg / mL; The heating rate is 4-10° C. / min, the steam treatment temperature is 100-180° C., and the steam treatment time is 60-300 min.

2. The method for post-sulfurization of antimony selenide sulfide thin film according to claim 1, characterized in that: The washing method is to use water and ethanol to clean respectively, and the drying method is to use N2 to blow dry.

3. The method for post-sulfurization of antimony selenide sulfide thin film according to claim 1 or 2, characterized in that: The specific process of the hydrothermal method is: potassium antimony tartrate, sodium thiosulfate and selenourea are mixed, hydrothermally reacted in a closed environment, and dried and annealed to obtain an antimony selenium sulfide film.

4. The method for post-sulfurization of antimony selenide sulfide thin film according to claim 3, characterized in that: The mass concentration of sodium sulfide in the sodium sulfide solution is 25 mg / mL, the heating rate is 7° C. / min, the steam treatment temperature is 140° C., and the steam treatment time is 180 min.

5. An antimony selenide sulfide thin film obtained by the method for post-sulfurization of an antimony selenide sulfide thin film according to any one of claims 1 to 4.

6. Use of the antimony selenide sulfide thin film according to claim 5 in a solar cell device, characterized in that: The solar cell device comprises the following structures: a cathode, an electron transport layer, a light absorption layer, a hole transport layer, and an anode. The light absorption layer in the solar cell device is the antimony selenide sulfide film.

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