A solar cell containing double-added antimony sulfide silver-based film and a preparation method thereof

Abstract

A double-addition antimony-sulfur silver-based film, wherein the double addition is the simultaneous addition of In (indium) and Sb (antimony), and the chemical expression of the film is AgIn x Sb 1+y (S, Se)2, where 0<x+y≤0.55. The present invention effectively removes the impurity phase in the film by adding both In and Sb, significantly improves the purity of the film, improves the crystallinity of the film, and the film shows a large-area uniform and dense morphology, effectively reduces the recombination of carriers, and finally improves the device Jsc and FF, thereby improving the photoelectric conversion efficiency from the original 1.98% to the current 2.43%.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic materials, and in particular to a solar cell containing a double-added antimony-sulfide silver-based film and a preparation method thereof. Background Art

[0002] SbS 2 (Antimony Sulfur Silver) is a new material with great potential for the absorption layer of thin-film solar cells, belonging to I-V-VI 2 The research on silver antimony sulfide as the absorption layer of solar cells at home and abroad started in 2012. PK Nair et al. first used AgSbS 2 Used in thin film solar cells. It has the following advantages: (1) AgSbS 2 The bandgap width is suitable, the bandgap width is 1.4~1.7eV; (2) AgSbS 2 With high absorption coefficient (10 4 -10 5 cm -1

[10] ), high absorption coefficient can not only reduce the amount of materials used in the production of solar cells, but also shorten the distance that carriers need to migrate and diffuse, thereby improving the carrier collection efficiency; (3) AgSbS 2 Has a lower melting point and better solubility; AgSbS 2 The melting point of AgSbS is 512°C, and such films can generally be sintered in the range of 300-400°C to obtain large-sized grains. The appropriate melting point can reduce the sintering temperature during the film preparation process, thereby reducing energy consumption; (4) AgSbS 2 The raw materials used are green and non-toxic, with abundant reserves, and are very suitable for large-scale production.

[0003] For pure AgSbS 2 One way to improve the electrical properties of thin films is to optimize the preparation process to make the film more crystallinity, larger grain size, more uniform overall morphology, and less defects. 2 The method to improve the performance of thin-film photovoltaics is through selenization. Since selenium atoms are larger than sulfur atoms, theoretically, according to the law that the band gap width is inversely proportional to the lattice parameter, the addition of selenium will reduce the AgSbS 2 The band gap width of the film is increased, thereby increasing its short-circuit current. PKNair et al. simplified the process to prepare AgSb(S x Se 1-x ) 2 The band gap of the film is 1.47Ve, and the maximum short-circuit current density of the film is estimated to be 29mA / cm3 in theory. 2 But the actual short-circuit current J of the device sc =2.07mA / cm 2, the efficiency is only 0.65%, which is far from the theoretical value of this material.

[0004] In order to improve the AgSb(S x Se 1-x ) 2 The optical properties of the film, CN113644146A uses In addition to prepare AgIn by spray drying pyrolysis x Sb (2+3x / 2) (Se) to increase the short-circuit current of the film and inhibit the diffusion of Se in the film, thereby adjusting the partial gradient of Se and improving the photoelectric conversion efficiency. The film prepared by adding In as the absorption layer of the solar cell ITO / CdS / Ag 1-x In 2x Sb 1-x S y Se 2-y Jsc of Au reaches 20.65 mA / cm 2 , PCE reached 1.98%. According to the bandgap width theory, its open circuit voltage should be 400-700mV, but the film still has a low open circuit voltage (220mV). After adding In, the film grain size is still small, resulting in the existence of intercrystalline gaps on the film surface, and the improvement of PCE is suppressed. Summary of the invention

[0005] Based on the above problems, the present invention aims to provide a dual-addition antimony sulfide silver-based film. The dual addition overcomes the above technical problems and effectively improves the PCE of the device.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned film.

[0007] The third object of the present invention is to provide a solar cell containing a double-doped antimony sulfur silver-based thin film.

[0008] The fourth object of the present invention is to provide a method for preparing the above-mentioned film.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A double-addition antimony-sulfur silver-based film, characterized in that: the double addition is the simultaneous addition of In (indium) and Sb (antimony), and the chemical expression of the film is AgIn x Sb 1+y (S,Se) 2 , where 0<x+y≤0.55.

[0011] Preferably, the AgIn x Sb 1+y (S,Se) 2 Where x=y=0.25.

[0012] Furthermore, the above AgIn x Sb 1+y (S,Se) 2 The film is AgNO 3 As Ag source, C 6 H 9 O 6 Sb is used as Sb source, SC(NH 2 ) 2 As the S source, InN 3 O 9 As In source, ethylene glycol methyl ether and acetic acid were used as solvents to prepare a precursor solution, which was prepared into a thin film by spray pyrolysis and then selenized.

[0013] The spray pyrolysis method is simple and efficient to prepare thin films, but the prepared thin films have small grain sizes and large defects, which makes the gradient distribution formed during the subsequent selenization less uniform, resulting in reduced film performance.

[0014] SbS 2 Directly adding In and Sb elements to AgSbS is different from the general substitution doping method, which is to add two elements without changing the original stoichiometric ratio. 2 The basic crystal structure of AgIn is retained, and the synergistic effect of Sb and In reduces the generation of impurities in the film, increases the crystallinity of the film, improves the density of the film, reduces surface defects, and improves the performance of the device. x Sb y S 2 The film is then heat treated with Se to replace a certain amount of S. During this process, the addition of Sb and In forms bonds with S at different strengths, which regulates the degree of substitution of Se and S, alleviates the distribution gradient of Se in the film, and prepares AgIn with a uniformly distributed gradient band structure. x Sb y (S,Se) 2 The film contains five elements, and the phase composition of the synthetic film is a single-phase solid solution, forming a high-entropy material. The short-circuit current of the device made of the film has been greatly improved.

[0015] Furthermore, the above AgNO 3 , C 6 H 9 O 6 Sb、SC(NH 2 ) 2 andIn(NO 3 ) 3 The molar ratio is 1:1-1.5:4:0.1-0.5.

[0016] The method for preparing the double-addition antimony-sulfur silver-based thin film is characterized in that: AgNO 3 andIn(NO 3 ) 3 Dissolve in ethylene glycol methyl ether, then add C 6 H 9 O 6 Sb acetic acid solution, and then add concentrated nitric acid, acetic acid and SC (NH 2 ) 2 , stirring and mixing to form a precursor solution, depositing a prefabricated film by spray pyrolysis, and then selenizing the prefabricated film, wherein AgNO 3 , C 6 H 9 O 6 Sb、SC(NH 2 ) 2 and C 6 H 9 O 6 The molar ratio of Sb is 1:1-1.5:4:0.1-0.5, C 6 H 9 O 6 Sb and C 6 H 9 O 6 The total molar ratio of Sb to AgNO 3 The molar ratio is no more than 1.55:1.

[0017] Furthermore, the temperature of the spray pyrolysis deposition is 330°C, with N 2 As carrier gas, the flow rate is 21L·min -1 The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the pre-film deposition is completed, it is allowed to cool down naturally.

[0018] A solar cell containing a double-doped antimony sulfide silver-based thin film, characterized in that: the solar cell is sequentially composed of an ITO substrate, a CdS buffer layer, an AgIn x Sb 1+y (S,Se) 2 The absorption layer and the Au electrode layer.

[0019] The method for preparing the solar cell containing the double-doped antimony sulfide silver-based thin film is characterized by being carried out according to the following steps:

[0020] Step 1: Clean the substrate

[0021] The conductive glass ITO was washed with deionized water, acetone, ethanol and ethanol in turn, then purged and dried with nitrogen, and finally cleaned with a UV ozone cleaner for 20 min;

[0022] Step 2: Preparation of CdS buffer layer

[0023] A CdS buffer layer was deposited on the ITO surface and then annealed at 400°C for 5 min. The thickness of the CdS buffer layer was 150 nm.

[0024] Step 3: Preparation of AgIn x Sb 1+y (S,Se) 2 film

[0025] (1) Preparation of precursor solution

[0026] AgNO 3 andIn(NO 3 ) 3 Dissolve in ethylene glycol methyl ether, then add C 6 H 9 O 6 Sb acetic acid solution, and then add concentrated nitric acid, acetic acid and SC (NH 2 ) 2 , stirring and mixing to form a precursor solution, depositing a prefabricated film by spray pyrolysis, and then selenizing the prefabricated film, wherein AgNO 3 , C 6 H 9 O 6 Sb、SC(NH 2 ) 2 and C 6 H 9 O 6 The molar ratio of Sb is 1:1-1.5:4:0.1-0.5, C 6 H 9 O 6 Sb and C 6 H 9 O 6 The total molar ratio of Sb to AgNO 3 The molar ratio of C is not more than 1.55:1. 6 H 9 O 6 Sb in acetic acid solution 6 H 9 O 6 The molar volume ratio of Sb and acetic acid is 1-1.5mmol:4mL;

[0027] (2) Spray pyrolysis deposition

[0028] The precursor solution was deposited into a prefabricated film by spray pyrolysis at a temperature of 330 °C with N 2 As carrier gas, the flow rate is 21L·min -1 The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the pre-film deposition is completed, it is allowed to cool naturally, and the film thickness is 950nm;

[0029] (3) Selenization

[0030] The prefabricated film is placed in the high temperature zone of the heat treatment furnace at a temperature of 400°C, the Se powder is placed in the low temperature zone at a temperature of 360°C, and the selenization time is 5-10 minutes to obtain AgIn x Sb 1+y (S,Se) 2 Absorbent layer;

[0031] Step 4: Preparation of Au Electrode

[0032] The thermal evaporation method was used in a vacuum of 3.5×10 -4 A Ag electrode with a thickness of 60 nm was deposited under Pa.

[0033] The present invention has the following technical effects:

[0034] The present invention effectively removes impurities in the film by dual addition of In and Sb, significantly improves the purity of the film, improves the crystallinity of the film, and displays a large-area uniform and dense morphology, effectively reducing the recombination of carriers. Ultimately, the device Jsc and FF are improved, thereby improving the photoelectric conversion efficiency from the original 1.98% to the current 2.43%. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 : Direct vacuum annealing of AgIn 0.25 Sb 1+y S 2 Thin film and selenized AgIn 0.25 Sb 1+y (S,Se) 2 XRD patterns of the films.

[0036] Figure 2 :AgSb(S,Se) 2 AgIn with different Ag / Sb thin films 0.25 Sb 1+y (S,Se) 2 Analysis of the chemical state of the film surface.

[0037] Figure 3:AgSb(S,Se) 2 AgIn with different Ag / Sb thin films 0.25 Sb 1+y (S,Se) 2 Surface and cross-sectional SEM images of the film.

[0038] Figure 4 :AgSbS 2 (Se) devices and AgIn with different Ag / Sb x Sb 2 (Se) Device JV characteristic curve.

[0039] Figure 5 :AgSbS 2 (Se) devices and AgIn with different Ag / Sb x Sb 2 (Se) Impedance spectrum of the device. DETAILED DESCRIPTION

[0040] The present invention is described in detail below through examples. It is necessary to point out that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above-mentioned contents of the present invention.

[0041] Comparative Example 1

[0042] Thin film AgSb with Sb added alone 1+y (S,Se) 2 The preparation of the solar cell as the absorption layer, the remaining steps are the same as in Example 1, except that there is no In(NO 3 ) 3 , by adjusting C 6 H 9 O 6 The amount of Sb was such that the Ag / Sb molar ratio in the film was 1:0.8, 1:1, 1:1.25 and 1.1.5 respectively to prepare different absorption layer films, namely AgSb 0.8 (S,Se) 2 、AgSb(S,Se) 2 、AgSb 1.25 (S,Se) 2 and AgSb 1.5 (S,Se) 2 The specific test performance is shown in Table 1.

[0043] Table 1: AgSb(S,Se) with different Ag / Sb 2 The main performance parameters of the device

[0044] Ag:Sb <![CDATA[V oc (V)]]> <![CDATA[J sc (mA cm -2 )]]> FF PCE(%) <![CDATA[R s (Ω·cm 2 )]]> 1:0.8 0.22±0.01 4.42±0.33 0.23±0.01 0.23±0.01 54.42±1.56 1:1 0.36±0.01 6.37±0.53 0.30±0.01 0.71±0.03 13.22±2.64 1:1.25 0.54±0.01 4.52±0.27 0.33±0.01 0.83±0.05 69.65±5.29 1:1.5 0.59±0.01 3.29±0.11 0.35±0.01 0.68±0.02 91.98±14.53

[0045] The results show that with the increase of Sb content, the V oc From 0.37V to 0.60V. But at the same time J sc The PCE also decreased, resulting in the final PCE not improving significantly as expected, and the PCE only increased from 0.74% to 0.88%.

[0046] Comparative Example 2

[0047] Thin film AgIn with In added alone x Sb(S,Se) 2 As the preparation of solar cells with absorption layers, such as CN113644146A, the effect of In addition on device performance is studied by adjusting the amount of In added. The performance parameters are shown in Table 4.

[0048] Table 2: AgIn with different Ag / In x Sb(S,Se) 2 The main performance parameters of the device

[0049] Ag:In <![CDATA[V oc (V)]]> <![CDATA[J sc (mA cm -2 )]]> FF PCE(%) <![CDATA[R s (Ω·cm 2 )]]> 1:0 0.33±0.06 5.54±2.15 0.31±0.03 0.75±0.05 14.87±0.98 1:0.25 0.23±0.01 14.24±0.29 0.40±0.01 1.28±0.03 5.25±0.31 1:0.4 0.22±0.01 17.04±0.32 0.34±0.01 1.33±0.15 4.92±0.53 1:0.55 0.22±0.01 19.76±0.67 0.44±0.06 1.84±0.12 4.67±0.29

[0050] Through testing, it was found that the above data were different from the data in CN113644146A due to different batches and changes in the testing environment, but the overall difference was small and within an acceptable range.

[0051] The addition of In significantly increased Jsc, which led to a certain improvement in PCE. However, the Voc also decreased to a certain extent, which restricted the improvement of PCE and was not as ideal as expected.

[0052] The effect of the Ag / In ratio on the carrier transport of the device was studied by performing frequency-dependent impedance tests on the device. The test was performed under zero bias and the scanning frequency was from 1Hz to 1MHz. It was found that R1 decreased with the increase of In, and CPE-P and τ avg It shows an upward trend. When Ag / In=1:0.55, R1 reaches the minimum value of 9.32Ω, CPE-P reaches the maximum value of 0.91, τ avg The maximum value reached is 9.96ms.

[0053] Example 1

[0054] The method for preparing the solar cell containing the double-doped antimony sulfide silver-based thin film is carried out according to the following steps:

[0055] Step 1: Clean the substrate

[0056] The conductive glass ITO was washed with deionized water, acetone, ethanol and ethanol in turn, then purged and dried with nitrogen, and finally cleaned with a UV ozone cleaner for 20 min;

[0057] Step 2: Preparation of CdS buffer layer

[0058] A CdS buffer layer was deposited on the ITO surface and then annealed at 400°C for 5 min. The thickness of the CdS buffer layer was 150 nm.

[0059] Step 3: Preparation of AgIn 0.25 Sb 1.25 (S,Se) 2 film

[0060] (1) Preparation of precursor solution

[0061] 0.58mmolAgNO 3 and 0.145mmolIn(NO 3 ) 3 Dissolve in 7.5 mL of ethylene glycol methyl ether, then add 0.725 mmol C 6 H 9 O 6 Then, 40 μL of 68% concentrated nitric acid, 0.3 mL of glacial acetic acid and 0.32 mmol of SC (NH 2 ) 2 , stirring and mixing to form a precursor solution;

[0062] (2) Spray pyrolysis deposition

[0063] The precursor solution was deposited into a prefabricated film by spray pyrolysis at a temperature of 330 °C with N 2 As carrier gas, the flow rate is 21L·min -1 The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the pre-film deposition is completed, it is allowed to cool naturally, and the thickness of the pre-film is 600nm;

[0064] (3) Selenization

[0065] The prefabricated film was placed in the high temperature zone of the heat treatment furnace at 400°C, the Se powder was placed in the low temperature zone at 360°C, and the selenization time was 8 minutes to obtain AgIn x Sb 1+y (S,Se) 2 Absorption layer film, film thickness is 950nm;

[0066] Step 4: Preparation of Au Electrode

[0067] The thermal evaporation method was used in a vacuum of 3.5×10 -4 The Ag electrode with a thickness of 60 nm was deposited at 400 Pa.

[0068] The other steps remained unchanged, and the molar ratio of Ag to Sb was used as the only variable to prepare AgIn with different Sb addition amounts. x Sb 1+y (S,Se) 2 Thin film. Specifically AgIn 0.25 Sb 1.1 (S,Se) 2 、AgIn 0.25 Sb 1.4 (S,Se) 2 and AgIn 0.25 Sb 1.4 (S,Se) 2 .

[0069] The above prefabricated film is directly annealed in a vacuum environment and the AgIn after selenization x Sb 1+y (S,Se) 2 The XRD patterns of the films are shown in Figure 2. Figure 1 (a) and Figure 1 As shown in (b), according to PDF card JCPDS17-0456, the XRD patterns of all films directly annealed under vacuum show a cubic phase (cubic AgSbS 2 ), but the film purity is low, and AgSbS 3 、AgSbO 3 , Sb 2 O 4 In this way, in the Ag-Sb-S system, Sb generates other oxidized impurities, resulting in a decrease in the amount of Sb entering the lattice, making the film preparation environment in the Ag-Sb-S system a Sb-poor environment, which will lead to poor device performance. However, when the Ag / Sb ratio increases, more Sb enters the lattice, and the purity is significantly improved, which effectively promotes the AgSbS 2 The film is synthesized, and after selenization, such as Figure 1 (b) shows AgSb(S,Se) 2 The film also contains AgSbS 2 and AgSbSe 2 phase, the impurities in the film are reduced. Ag / Sb=1:1.25 AgIn x Sb 2 The diffraction peak intensity of the (Se) film increased significantly, indicating that the grain size of the film increased and the crystallinity improved.

[0070] XPS test reveals the chemical state of the surface of the prepared film. AgSb(S,Se) 2 Thin film and AgIn with Ag / Sb ratio of 1:1.00 and 1:1.25 x Sb(S,Se) 2 The XPS spectrum of the film is as follows Figure 2 As shown in (a), except for the In element, the element binding energies in the two films are similar. AgSb(S,Se) 2 Thin film and AgIn with Ag / Sb of 1:1.00, 1:1.25 and 1:1.40 x Sb(S,Se) 2 The Ag 3d, In 3d and Sb 3d fine scanning spectra of the film are as follows: Figure 2 As shown in (b)-(f), the XPS peaks of Ag 3d, In 3d, and Sb 3d move toward the low binding energy direction, indicating that the position of the cations in the lattice has changed, and more Sb atoms have entered the lattice. Since the proportion of In in the total amount of cations remains basically unchanged, the peak intensity of the In 3d peak remains basically unchanged. As the Sb content continues to increase, the peak intensity of the Sb 3d peak increases, which is consistent with the results of the EDS test (Table 1). Figure 2 (e) and Figure 2 As shown in (f), the XPS peaks in the binding energy range of 526-534 eV show asymmetric linearity and can be regarded as the superposition of multiple peaks. These correspond to the bonding of Sb and Se atoms, the bonding of Sb and S atoms, and the O peak accompanied by the Sb 3d peak. With the increase of Sb content, more Sb atoms on the surface of the film are combined with S atoms, and the anions on the surface of the film are mainly controlled by S, which prevents the device performance degradation caused by excessive selenization.

[0071] Through the composition analysis of the film, AgIn x Sb 1+y (S,Se) 2 The relative contents of Ag, In, Sb, S, and Se elements in the film are shown in Table 3.

[0072] Table 3: AgSb(S,Se) measured by EDS 2 and AgIn with different Ag / Sb x Sb 1+y (S,Se) 2 Element ratio of thin film

[0073]

[0074] The above deposited AgSb(S,Se) 2AgIn films with Ag / Sb ratios of 1:1.00, 1:1.10, 1:1.20, 1:1.25, 1:1.30, and 1:1.40 x Sb 2 The element ratio in the (Se) film is AgIn x Sb 1+y (S,Se) 2 The statistical average of 12 points randomly selected in the film. According to EDS analysis, AgSb(S,Se) 2 Thin film and AgIn with Ag / Sb=1:1.00 x Sb 1+y (S,Se) 2 The Sb content in the film is slightly less. x Sb 1+y (S,Se) 2 In the film, because the content of In remains unchanged during the preparation process, its proportion in the total amount of cations remains basically unchanged. The Ag / Sb of the deposited film measured by EDS is 1:0.94, 1:1.07, 1:1.15, 1:1.19, 1:1.24 and 1:1.33, which is basically consistent with the change trend of Ag / Sb after the Sb content increases. It can be seen that both Sb and In have been effectively added, rather than conventional doping.

[0075] AgSb(S,Se) 2 Thin films and AgIn with different Ag / Sb x Sb 1+y (S,Se) 2 The SEM images of the films are shown in Figure 3 As shown. SEM images provide texture and morphology information of the film. Figure 3 (a)-(d) show AgSb(S,Se) 2 Thin film and AgIn with Ag / Sb of 1:1.00, 1:1.25 and 1:1.40 x Sb 2 (Se) SEM image of the film surface, Figure 3 (e) shows a larger surface SEM image of the film with Ag / Sb = 1:1.25. It can be seen that AgSb(S,Se) 2 The film presents a relatively loose structure, with small grains that have not fully grown. Poor crystallinity leads to weak adhesion to the underlying CdS layer. After adding a small amount of In, the film surface presents a dense morphology, but the grain size is slightly smaller, and there are still intercrystalline gaps on the film surface. On this basis, Sb is added. As Sb increases, Ag / Sb = 1:1.25 AgIn x Sb 1+y (S,Se) 2The grain size of the film is significantly increased, and there are no obvious pores on the surface. Figure 3 (e) It can be seen that the film shows a large area of ​​uniform morphology, which does not change due to the different film positions. Its cross-sectional structure and heterojunction interface are shown in Figure 2. Figure 3 (f). However, as the Sb content continues to increase, the overall morphology of the film slightly deteriorates due to the increase in voids between grain boundaries. Therefore, the best performance can be obtained when Ag / Sb reaches 1:1.25.

[0076] The JV characteristic curve of the device is as follows: Figure 4 The main performance parameters of the device measured are shown in Table 4. Combining the analysis results of the film XRD test, the analysis results of the film morphology structure of the SEM image and the analysis results of the film band structure, it can be seen that the appropriate increase in Sb content can promote the synthesis of the material and improve the crystallinity of the film. A more uniform and dense film and a more suitable band structure can reduce the recombination probability of carriers and improve the FF of the device.

[0077] Table 4: AgSb(S,Se) 2 and AgIn with different Ag / Sb 0.25 Sb(S,Se) 2 The main performance parameters of the device

[0078] Cell(ratio) <![CDATA[V oc (V)]]> <![CDATA[J sc (mA cm -2 )]]> FF PCE(%) <![CDATA[R s (Ω·cm 2 )]]> <![CDATA[AgSb(S,Se) 2 ]]> 0.33±0.06 5.54±2.15 0.31±0.03 0.75±0.05 14.87±0.98 Ag / Sb=1:100 0.23±0.01 14.24±0.29 0.40±0.01 1.28±0.03 5.25±0.31 Ag / Sb=1:1.25 0.24±0.01 18.11±0.95 0.53±0.01 2.38±0.05 2.45±0.04 Ag / Sb=1:1.30 0.24±0.01 16.19±0.39 0.48±0.01 1.88±0.02 3.72±0.03 Ag / Sb=1:1.40 0.23±0.01 12.22±0.35 0.44±0.01 1.27±0.05 5.58±0.49

[0079] The films were prepared by in-situ spray pyrolysis followed by selenization treatment and 2 Based on the double addition of In and Sb, and the AgIn x Sb(S,Se) 2 The results show that when Sb is added alone, the V oc When In and Sb are added together, Voc is close to that when In is added alone, and Sb does not show the effect of improving Voc. However, the purity of the film is significantly improved, the crystallinity of the film is improved, and the film shows a large area of ​​uniform and dense morphology. When In is added alone, when x = 0.25, Jsc reaches 14.54mA·cm -2 , but it has no significant effect on the improvement of FF. In the solution of adding Sb alone, when y=0.25, Jsc reaches 4.79mA·cm -2 , and less added AgSb(S,Se) 2 For the case of In and Sb, Jsc is reduced and the effect on improving FF is not obvious. However, in the case of In and Sb dual addition, when x=y=0.25, Jsc reaches 19.06mA·cm-2 However, when x+y>0.55, its Jsc decreases, which is lower than that of adding In alone. It can be seen that the dual addition of In and Sb produces a synergistic effect, effectively improving Jsc, and at the same time, FF is also significantly improved. Regarding the improvement of Jsc, it can be clearly seen from the series resistance that when Sb is added alone, Rs shows an upward trend with the increase of Sb. When In is added alone, it decreases slightly compared with no In addition, but when In and Sb are added at the same time, Rs decreases significantly.

[0080] In order to further study the effect of the addition of In and Sb in the dual addition on the carrier transport in the device, the device was subjected to frequency-dependent impedance analysis. The test was conducted under zero bias with a sweep frequency of 1 Hz to 1 MHz. The impedance parameters calculated from the fitting curve of the test are shown in Table 5.

[0081] Table 5: Impedance parameters of the device obtained from the fitted impedance spectrum

[0082] <![CDATA[R 1 (Oh)]]> <![CDATA[CPE-T(F·cm -2 )]]> CPE-P <![CDATA[R 2 (Oh)]]> <![CDATA[τ avg (ms)]]> <![CDATA[AgSb(S,Se) 2 ]]> 126.10 <![CDATA[9.942×10 -8 ]]> 0.78 77008 7.66 <![CDATA[AgIn 0.55 Sb(S,Se) 2 ]]> 9.32 <![CDATA[1.662×10 -6 ]]> 0.91 6548 9.96 <![CDATA[AgIn 0.25 Sb(S,Se) 2 ]]> 35.79 <![CDATA[4.061×10 -7 ]]> 0.90 21475 8.72 <![CDATA[AgIn 0.25 Sb 1.1 (S,Se) 2 ]]> 53.14 <![CDATA[2.602×10 -7 ]]> 0.91 31762 8.26 <![CDATA[AgIn 0.25 Sb 1.2 (S,Se) 2 ]]> 15.37 <![CDATA[9.362×10 -7 ]]> 0.92 10510 9.84 <![CDATA[AgIn 0.25 Sb 1.25 (S,Se) 2 ]]> 11.77 <![CDATA[1.342×10 -6 ]]> 0.94 7435 9.98 <![CDATA[AgIn 0.25 Sb 1.3 (S,Se) 2 ]]> 19.35 <![CDATA[5.284×10 -7 ]]> 0.91 17940 9.47 <![CDATA[AgIn 0.25 Sb 1.4 (S,Se) 2 ]]> 40.82 <![CDATA[3.479×10 -7 ]]> 0.86 24006 8.35

[0083] In AgIn with In added alone x Sb(S,Se) 2 In the film, as In increases to x = 0.55, R1 reaches a minimum value of 9.32Ω, CPE-P reaches a maximum value of 0.91, τ avg The maximum value is 9.96ms. The AgIn prepared by adding both In and Sb in the present invention x Sb 1+y (S,Se) 2 The CPE-P of the film reaches a maximum value of 0.94 when x=y=0.25, which means that the adjustment of Ag / Sb improves the contact quality of the heterojunction interface. At the same time, the device also has the lowest R 1 and the highest CPE1-T with τ avg . Longer τ avg Indicates a lower carrier recombination rate, which indicates that the device has the lowest carrier recombination.

[0084] Finally, the device's J sc Both FF and photoelectric conversion efficiency of the device are improved effectively to 2.43%.

[0085] Example 2

[0086] The above contains double added AgIn 0.3 Sb 1.1 (S,Se) 2 The method for preparing a solar cell of antimony sulfide silver-based thin film is carried out according to the following steps:

[0087] Step 1: Clean the substrate

[0088] The conductive glass ITO was washed with deionized water, acetone, ethanol and ethanol in turn, then purged and dried with nitrogen, and finally cleaned with a UV ozone cleaner for 20 min;

[0089] Step 2: Preparation of CdS buffer layer

[0090] A CdS buffer layer was deposited on the ITO surface and then annealed at 400°C for 5 min. The thickness of the CdS buffer layer was 150 nm.

[0091] Step 3: Preparation of AgIn 0.3 Sb 1.1 (S,Se) 2 film

[0092] (1) Preparation of precursor solution

[0093] 0.58mmolAgNO 3 and 0.174mmolIn(NO 3 ) 3 Dissolve in 7.5 mL of ethylene glycol methyl ether, then add 0.638 mmol C 6 H 9 O 6 Then, 40 μL of 68% concentrated nitric acid, 0.3 mL of glacial acetic acid and 0.32 mmol of SC (NH 2 ) 2 , stirring and mixing to form a precursor solution;

[0094] (2) Spray pyrolysis deposition

[0095] The precursor solution was deposited into a prefabricated film by spray pyrolysis at a temperature of 330 °C with N 2 As carrier gas, the flow rate is 21L·min -1 The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the pre-film deposition is completed, it is allowed to cool naturally, and the thickness of the pre-film is about 600nm;

[0096] (3) Selenization

[0097] The prefabricated film was placed in the high temperature zone of the heat treatment furnace at 400°C, the Se powder was placed in the low temperature zone at 360°C, and the selenization time was 10 min to obtain AgIn 0.3 Sb 1.1 (S,Se) 2 Absorption layer, film thickness is 1000nm;

[0098] Step 4: Preparation of Au Electrode

[0099] The thermal evaporation method was used in a vacuum of 3.5×10 -4 The Ag electrode with a thickness of 60 nm was deposited at 400 Pa.

[0100] Example 3

[0101] The above contains double added AgIn 0.1 Sb 1.3 (S,Se) 2 The method for preparing a solar cell of antimony sulfide silver-based thin film is carried out according to the following steps:

[0102] Step 1: Clean the substrate

[0103] The conductive glass ITO was washed with deionized water, acetone, ethanol and ethanol in turn, then purged and dried with nitrogen, and finally cleaned with a UV ozone cleaner for 20 min;

[0104] Step 2: Preparation of CdS buffer layer

[0105] A CdS buffer layer was deposited on the ITO surface and then annealed at 400°C for 5 min. The thickness of the CdS buffer layer was 150 nm.

[0106] Step 3: Preparation of AgIn 0.1 Sb 1.3 (S,Se) 2 film

[0107] (1) Preparation of precursor solution

[0108] 0.58mmolAgNO 3 and 0.058mmolIn(NO 3 ) 3 Dissolve in 7.5 mL of ethylene glycol methyl ether, then add 0.754 mmol C 6 H 9 O 6 Then, 40 μL of 68% concentrated nitric acid, 0.3 mL of glacial acetic acid and 0.32 mmol of SC (NH 2 ) 2 , stirring and mixing to form a precursor solution;

[0109] (2) Spray pyrolysis deposition

[0110] The precursor solution was deposited into a prefabricated film by spray pyrolysis at a temperature of 330 °C with N 2 As carrier gas, the flow rate is 21L·min -1The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the prefabricated film is deposited, it is allowed to cool naturally;

[0111] (3) Selenization

[0112] The prefabricated film was placed in the high temperature zone of the heat treatment furnace at 400°C, the Se powder was placed in the low temperature zone at 360°C, and the selenization time was 6 minutes to obtain AgIn 0.1 Sb 1.3 (S,Se) 2 Absorption layer, film thickness is 920nm;

[0113] Step 4: Preparation of Au Electrode

[0114] The thermal evaporation method was used in a vacuum of 3.5×10 -4 The Ag electrode with a thickness of 60 nm was deposited at 400 Pa.

Claims

1. A double-addition antimony sulfide silver-based film, characterized in that: The double addition is to add In (indium) and Sb (antimony) at the same time, and the chemical expression of the film is AgIn x Sb 1+y (S,Se)2, where 0<x+y≤0.

55.

2. A dual-addition antimony sulfide silver-based film as claimed in claim 1, characterized in that: The AgIn x Sb 1+y The (S,Se)2 film is prepared by spray pyrolysis using AgNO3 as the Ag source, C6H9O6Sb as the Sb source, SC(NH2)2 as the S source, InN3O9 as the In source, and ethylene glycol methyl ether and acetic acid as solvents to prepare a precursor solution, and then selenization is performed.

3. A dual-addition antimony sulfide silver-based film as claimed in claim 2, characterized in that: The molar ratio of AgNO3, C6H9O6Sb, SC(NH2)2 and In(NO3)3 is 1:1-1.5:4:0.1-0.

5.

4. A double-addition antimony sulfide silver-based film according to any one of claims 1 to 3, characterized in that: The preparation method of the double-added antimony-sulfide silver-based film is characterized in that: AgNO3 and In(NO3)3 are dissolved in ethylene glycol methyl ether, and then an acetic acid solution of C6H9O6Sb is added, and then concentrated nitric acid, acetic acid and SC(NH2)2 are added in sequence, stirred and mixed to form a precursor solution, a prefabricated film is deposited by spray pyrolysis, and then the prefabricated film is selenized, wherein the molar ratio of AgNO3, C6H9O6Sb, SC(NH2)2 and In(NO3)3 is 1:1-1.5:4:0.1-0.5, and the molar ratio of the total molar sum of C6H9O6Sb and In(NO3)3 to AgNO3 is not more than 1.55:

1.

5. A solar cell comprising the double-additive antimony sulfide silver-based thin film according to any one of claims 1 to 4, characterized in that: The solar cell is composed of an ITO substrate, a CdS buffer layer, an AgIn x Sb 1+y It consists of a (S,Se)2 absorption layer and an Au electrode layer.

6. The method for preparing a solar cell containing a double-added antimony sulfide silver-based thin film according to claim 5, characterized in that: Proceed as follows: Step 1: Clean the substrate The conductive glass ITO was washed with deionized water, acetone, ethanol and ethanol in turn, then purged and dried with nitrogen, and finally cleaned with a UV ozone cleaner for 20 min; Step 2: Preparation of CdS buffer layer A CdS buffer layer was deposited on the ITO surface and then annealed at 400°C for 5 min. The thickness of the CdS buffer layer was 150 nm. Step 3: Preparation of AgIn x Sb 1+y (S,Se)2 Thin Film (1) Preparation of precursor solution Dissolve AgNO3 and In(NO3)3 in ethylene glycol methyl ether, add C6H9O6Sb acetic acid solution, add concentrated nitric acid, acetic acid and SC(NH2)2 in sequence, stir and mix to form a precursor solution, deposit a prefabricated film by spray pyrolysis, and then selenize the prefabricated film, wherein the molar ratio of AgNO3, C6H9O6Sb, SC(NH2)2 and In(NO3)3 is 1:1-1.5:4:0.1-0.5, the molar ratio of the total molar amount of C6H9O6Sb and In(NO3)3 to AgNO3 is no more than 1.55:1, and the molar volume ratio of C6H9O6Sb and acetic acid in the C6H9O6Sb acetic acid solution is 1-1.5mmol:4mL; (2) Spray pyrolysis deposition The precursor solution was deposited into a prefabricated film by spray pyrolysis at a temperature of 330 °C and N2 as the carrier gas at a flow rate of 21 L min -1 The feed rate of the precursor solution was controlled at 0.3 mL min -1 The deposition rate was maintained at 150 nm min -1 After the pre-film deposition is completed, it is allowed to cool naturally, and the film thickness is 950nm; (3) Selenization The prefabricated film is placed in the high temperature zone of the heat treatment furnace at a temperature of 400°C, the Se powder is placed in the low temperature zone at a temperature of 360°C, and the selenization time is 5-10 minutes to obtain AgIn x Sb 1+y (S,Se)2 absorption layer; Step 4: Preparation of Au Electrode The thermal evaporation method was used in a vacuum of 3.5×10 -4 A Ag electrode with a thickness of 60 nm was deposited under Pa.

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