Materials
·
2023
·Vol. 16
·期 7
·2869
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IF 3.4
Quanzhen Sun,Jianlong Tang,Caixia Zhang,Yaling Li,Weihao Xie,Hui Deng,Qiao Zheng,Jionghua Wu,Shuying Cheng
Flexible CZTSSe solar cells have attracted much attention due to their earth-abundant elements, high stability, and wide application prospects. However, the environmental problems caused by the high toxicity of the Cd in the buffer layers restrict the development of flexible CZTSSe solar cells. Herein, we develop a Cd-free flexible CZTSSe/ZnO solar cell. The influences of the ZnO films on device performances are investigated. The light absorption capacity of flexible CZTSSe solar cells is enhanced due to the removal of the CdS layer. The optimal thickness of the ZnO buffer layers and the appropriate annealing temperature of the CZTSSe/ZnO are 100 nm and 200 °C. Ultimately, the optimum flexible CZTSSe/ZnO device achieves an efficiency of 5.0%, which is the highest efficiency for flexible CZTSSe/ZnO solar cells. The systematic characterizations indicate that the flexible CZTSSe/ZnO solar cells based on the optimal conditions achieved quality heterojunction, low defect density and better charge transfer capability. This work provides a new strategy for the development of the environmentally friendly and low-cost flexible CZTSSe solar cells.Keywords:Cd-free flexible CZTSSe/ZnO solar cells;ZnO buffer layer;CZTSSe/ZnO heterojunction;buffer layer optimization
研究领域:
材料科学
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太阳能
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Changcheng Cui,Junjie Fu,Dongxing Kou,Yimeng Li,Hao Wei,Zucheng Wu,Wenhui Zhou,Zhengji Zhou,Shengjie Yuan,Yafang Qi,Shuping Pang,Zhipeng Shao,Sixin Wu,Guanglei Cui
The Cu 2 ZnSn(S,Se) 4 solar cells (CZTSSe) are emerging as a hot area of low-cost thin film photovoltaic technology owing to its non-toxicity and excellent photoelectric properties. However, the large open-circuit voltage deficit ( V oc,deficit ) caused by the inherently defective CdS/ CZTSSe heterojunction interface is still a huge challenge for improving power conversion efficiency. Herein, we reconstruct the heterojunction interface by inserting a CZTSSe:In into the CdS/CZTSSe heterojunction through an In 2 Se 3 post-deposition treatment. The local occupation of In 3+ at Zn 2+ and Sn 4+ sites decreases the disordered Zn- and Sn-related deep defects and generates benign In Zn donors within CZITSSe transition layer simultaneously, which effectively enhances the surface p-to-n conversion. The combination of chemical and field-effect passivation regulates the charge extraction and passivates the charge recombination. As a result, the In element-buried absorber enables the V oc boost from 488 to 527 mV with an impressive active-area efficiency of 13.59 %. These results demonstrate the great potential of the In element-buried absorber in alleviating the V oc,deficit and enhancing the performance of CZTSSe solar cells.
研究领域:
材料科学
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光伏技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Sijie Ge,Xuanzhi He,Qianli Zhang,Junjie Lin,Yuchang Zeng,Yudiao Lin,Conglong Lin,Yan Zhang,Xianzhong Lin
A binary solvent system of dimethyl sulfoxide (DMSO) and isopropanol (IPA) has been developed for preparing high-crystalline kesterite Cu2ZnSn(S,Se)4 (CZTSSe) films. The absorbers made with the single DMSO solvent exhibit a granular microstructure, which can be altered by adding IPA to the solvent. Addition of IPA not only elevates wettability of the solution, but also enhances its volatility, thus enabling the regulation of the formation of cracks in the precursor thin film. Appropriate cracks allow Se vapor to penetrate the precursor film which promotes the grain growth during the selenization process. Hence, the incorporation of IPA into the solvent impacts the crystallinity of the absorber. Large grains can be obtained when the volume ratio of DMSO to IPA is 4 : 1. Both the open-circuit voltage (VOC) and fill factor (FF) are dramatically improved by around 24% and 47%, respectively, with the addition of 20% IPA. As a result, the efficiency of the CZTSSe solar cell has increased from 3.33% to 7.18%.
研究领域:
材料科学
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太阳能技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Yaowei Wei,Ke Zhou,Xianghuan Meng,Xiangyu Sun,Zhao Ma,Zhenzhen Li,Daming Zhuang
Due to the low toxicity and abundance of nature, Cu 2 ZnSn(S,Se) 4 (CZTSSe) has been considered as a promising solar cell material. The absorber is the most critical structure in a solar cell, which determines the performance of the cell. Selenium-rich CZTSSe can be formed by replacing S atoms of CZTS with Se. However, the method of adding Se element through H 2 Se is constrained due to the toxicity of H 2 Se. The work adopted a method to prepare excellent CZTSSe absorbers without H 2 Se. The stack structure CZTS precursor films were prepared by solution-based deposition, and CZTSSe absorbers were obtained after selenization annealing at 550 °C with 0.1, 0.2 and 0.3 g of selenium powders in argon, respectively. The obtained CZTSSe absorbers had pure CZTSSe phase, high absorption coefficients and appropriate bandgaps. After annealing with 0.2 g of selenium powder, the holes in the CZTSSe film diminished, and the grain size of absorbers increased from 0.31 µm in the CZTS absorber to 1.17 µm. The peaks of Se 3d for CZTSSe absorber were observed, the lattice spacing of plane (112) increased from 3.10 Å to 3.22 Å, and the work function decreased from 5.31 eV to 5.19 eV. The improved performance of absorber will be of great significance for the efficiency of CZTSSe device.
研究领域:
材料科学
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太阳能电池研究
✓ 已验证
产品关联
DOI
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2023
·
IF 2.8
Yawei Wang,Lingling Wang,Yanqin Wang,Xiangyang Zhao,Xingyu Zhang,Xintong Zhang,Yichun Liu
Replacing the traditional CdS buffer layer with more environmentally friendly materials is an urgent issue for environment-friendly CZTSSe solar cells. Herein, a nontoxic, flexible, and conductive organic molecular semiconductor PCBM to replace CdS is used and a Cd-free CZTSSe solar cell is obtained. By introducing mild spin-coated ZnO window layers, the damage of PCBM in conventional sputtering ZnO process is effectively avoided, and a higher efficiency than previously reported organic semiconductor buffer layer systems and comparable to CdS buffer layer devices are achieved. The flexible PCBM covers the surface of the CZTSSe absorber layer densely and forms a flatter film surface, which is beneficial for the following ZnO deposition. The CZTSSe/PCBM interface exhibits a typical “spike-like” energy band alignment with a conduction band offset value of only 0.1 eV. Compared with CZTSSe/CdS interface, the CZTSSe/PCBM heterojunction possesses larger interfacial recombination resistance and a longer carrier lifetime. The ideal coating ability, suitable energy band alignment, as well as the better interface carriers transfer behavior suggest that the organic molecular semiconductors can be used instead of the CdS buffer layer to pave the way for truly environment-friendly kesterite photovoltaic devices.
研究领域:
材料科学
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可再生能源
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环境科学
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2021
·
IF 7.267
Hai-Qin Xiao,Wen-Hui Zhou,Dong-Xing Kou,Zheng-Ji Zhou,Yue-Na Meng,Ya-Fang Qi,Sheng-Jie Yuan,Li-Tao Han,Zhi Zheng,Si-Xin Wu
Se-rich selenization offers remarkable benefits for grain growth of Cu 2 ZnSn(S,Se) 4 (CZTSSe) absorber layers , which is critical for solar cells fabrication. However, low-activity selenium often forms Se-clusters and trapped in CZTSSe absorber layers. These trapped Se-clusters increase carrier recombination in CZTSSe absorber layers, thus decreasing efficiency of CZTSSe solar cells. Herein, supercritical carbon dioxide (SCCO 2 ) treatment was demonstrated to regulate selenium composition of CZTSSe absorber layers for solar cells efficiency improvement. Compared with untreated CZTSSe absorber layers, selenium composition of CZTSSe absorber layers were significantly reduced by SCCO 2 treatment. The open circuit voltage ( V OC ) and fill factor (FF) of CZTSSe solar cells improved pronouncedly due to carrier recombination reduction and carrier transport enhancement. As a consequence, the power conversion efficiency (PCE) was increased from 9.26 % (ref device) to 11.43 % (SCCO 2 device). This unique SCCO 2 treatment may offer new ideas for other selenization-based optoelectronic devices performance improvement.
研究领域:
材料科学
·
光伏技术
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2024
·
IF 6.3
Yutian Wang,Jingyuan Guo,Letu Siqin,Chenjun Yang,Lei Wang,Shuyu Li,Ruijian Liu,Hongmei Luan,Chengjun Zhu
Defect modulation is one of the key factors in determining the performance of solar cells, and the presence of defects tends to adversely affect carrier recombination and transport, thus having a direct impact on both cell stability and efficiency. Ag doping can modulate the defects, but in-depth studies on the mechanism of the effect are needed. Therefore, an in-depth study of the effect of Ag incorporation on the defect modulation mechanism of Kesterite Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells is of great practical significance for understanding the mechanism of action of Ag doping and further optimising the cell performance. In this study, (Ag x Cu 1-x ) 2 ZnSn(S,Se) 4 (0 ≤ x ≤ 1) (ACZTSSe) solar cells were successfully prepared by N, N-dimethylformamide (DMF) solution, which have the characteristics of reducing defects and enhancing photovoltaic performance. After the introduction of Ag, the absorber formed a crystal structure with few holes and penetrating top and bottom. And the electrical performance of the solar cell is significantly improved, J 0 is reduced from 4.6 × 10 −5 A/cm 2 to 2.7 × 10 −6 A/cm 2 , and its contribution to the photovoltaic conversion efficiency (PCE) improvement reaches 142%. This indicates that the introduction of Ag helps to optimize the quality of the absorber, thereby reducing the concentration of interfacial and bulk defects. It also reduces carrier recombination and improves carrier lifetime from 0.86 ms to 1.75 ms. Ultimately increasing our cell efficiency from 7.55% to 10.64% when the Ag content reached 5%. These results clearly show that we have successfully achieved the modulation of defects in CZTSSe solar cells by Ag doping.
研究领域:
材料科学
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可再生能源
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光伏技术
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·
IF 13
Wentong Yang,Yixiong Ji,Wangxian Chen,Yining Pan,Zifei Chen,Shaoyang Wu,Salvy P. Russo,Yang Xu,Trevor A. Smith,Anthony Chesman,Paul Mulvaney,Fangyang Liu
Sodium (Na) doping is a well-established technique employed in chalcopyrite and kesterite solar cells. While various improvements can be achieved in crystalline quality, electrical properties, or defect passivation of the absorber materials by incorporating Na, a comprehensive demonstration of the desired Na distribution in CZTSSe is still lacking. Herein, a straightforward Na doping approach by dissolving NaCl into the CZTS precursor solution is proposed. It is demonstrated that a favorable Na ion distribution should comprise a precisely controlled Na + concentration at the front surface and an enhanced distribution within the bottom region of the absorber layer. These findings demonstrated that Na ions play several positive roles within the device, leading to an overall power conversion efficiency of 12.51%.
研究领域:
材料科学
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可再生能源
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光伏技术
✓ 已验证
DOI
高影响因子
Solar RRL
·
2023
·Vol. 7
·期 9
·2300006
·
IF 7.9
Yue Jian,Tianliang Xie,Litao Han,Lei Cao,Lijing Wang,Wenhui Zhou,Zhengji Zhou,Dongxing Kou,Yuena Meng,Yafang Qi,Shengjie Yuan,Sixin Wu
Thermally evaporated Se, including the molecules of Se 2 , Se 5 , Se 6 , Se 7 , and Se 8 in the vapor at 550–600 °C, is widely used for the selenization of CZTSSe films. However, active small-molecule Se 2 tends to form large clusters of Se atoms at saturation vapor pressure, resulting in the large Se deficiency and poor crystallization of CZTSSe films. To regulate the time for Se to reach saturation vapor pressure and promote the role of active small-molecule Se, the evaporation area of Se is controlled. Then the corresponding grain growth mechanism of CZTSSe films and device efficiency are systematically investigated. The results demonstrate that the appropriate evaporation area of Se can not only optimize the time for Se vapor to reach saturation, promote the rapid reaction crystallization between the precursor films and active Se 2 , but also inhibit the nucleation at the CZTSSe/Mo interface, thus making the CZTSSe films show a perfect top-down grain growth mode. By preliminary optimization, when the evaporation area of Se is 245 mm 2 , a large-grain spanning monolayer CZTSSe thin film is obtained; meanwhile, a device with a high efficiency of 12.39% is achieved. This study provides a new selenization strategy for improving the crystallinity of CZTSSe thin films.
研究领域:
材料科学
·
太阳能电池研究
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Biwen Duan,Licheng Lou,Fanqi Meng,Jiazheng Zhou,Jinlin Wang,Jiangjian Shi,Huijue Wu,Yanhong Luo,Dongmei Li,Qingbo Meng
The post-heating treatment of the CZTSSe/CdS heterojunction can enhance the interfacial properties of kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. In this regard, a two-step annealing method was developed to enhance the heterojunction quality for the first time. That is, a low-temperature (90 °C) process was introduced before the high-temperature treatment, and 12.3% efficiency of CZTSSe solar cells was achieved. Further investigation revealed that the CZTSSe/CdS heterojunction band alignment with a smaller spike barrier can be realized by the two-step annealing treatment, which assisted in carrier transportation and reduced the charge recombination loss, thus enhancing the open-circuit voltage (VOC) and fill factor (FF) of the devices. In addition, the two-step annealing could effectively avoid the disadvantages of direct high-temperature treatment (such as more pinholes on CdS films and excess element diffusion), improve the CdS crystallization, and decrease the defect densities within the device, especially interfacial defects. This work provides an effective method to improve the CZTSSe/CdS heterojunction properties for efficient kesterite solar cells.
研究领域:
材料科学
·
光伏技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Lixin Zhang,Junfeng Zhang,Yasong Cui,Yankun Lan,Jing Yu
Alkali metal doping is considered as an effective strategy in the pathway of improving the efficiency of Cu 2 ZnSn(S,Se) 4 (CZTSSe) photovoltaic materials. In this paper, Li is successfully doped into CZTSSe films in air and high efficiency devices are obtained. By X-ray diffraction and scanning electron microscopy, it can be found that the crystalline quality of CZTSSe films after Li doping is effectively improved and full and dense absorber layer crystals are obtained. In addition, TRPL also shows that the carrier lifetime of CZTSSe by doping with Li is significantly enhanced. Lithium-doped CZTSSe thin-film solar cells finally achieve a high efficiency of 9.84%. This Li doping route with simple process and superior device performance obtained provides a new idea for further development of element-rich and non-toxic CZTSSe thin film materials.
研究领域:
材料科学
·
太阳能技术
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2022
·
IF 7.305
Chao Gao,Wenbo Li,Xiaowei Zhou,Haoyu Xu,Qing Zhou,Haifeng Gao,Shumin Qin,Zeran Gao,Wei Yu
Multi-layer crystallization and uncontrollable defects were the main factors that limiting the quality of Cu 2 ZnSn(S,Se) 4 (CZTSSe) films. Here a hybrid crystallization strategy was proposed to simultaneously improve the morphology and defect properties of CZTSSe film. Firstly, we found the variation of the microstructures (constitution, chemical environment of the elements, etc.) in precursor films can greatly alter the grain-growths of CZTSSe films. Detailed characterizations revealed that the chemical environment of S in the precursor film may influence the S-to-Se substitution of the film during the selenization process. This can further affect the grain-growth mechanism and the properties of CZTSSe film. While the S-to-Se substitution of the film mainly occurred below 500°C, the NaSe x on the surface of the film could dominate the grain-growth (Na-mechanism). For this mechanism, the CZTSSe film exhibited bi-layer morphology and relatively high band-tail energy, but shallow-acceptor was detected in the film. The solar cells based on the CZTSSe films reached the efficiency of 10.6%. As a comparison, liquid phase could be generated when the S-to-Se substitution of the film shifted to higher temperature (>500°C). In this condition, the grain-growth would be dominated by the liquid phase (LP-mechanism). Such mechanism can eliminate the multi-layer crystallization and reduce the band-tail energy, but the surface properties of the CZTSSe film was deteriorated and the formation of shallow-acceptor in CZTSSe was inhibited. The fabricated solar cells achieved the efficiency of 10.3%. Based on the results above, a bi-layer precursor film contained sub-layers with different microstructures was proposed to regulate the crystallization of CZTSSe. The co-existence of different microstructures in the precursor film could induce a hybrid grain-growth mechanism for the CZTSSe film (e.g., the Na-mechanism worked on the surface while the LP-mechanism worked in the bottom simultaneously). Such grain-growth mechanism can yield CZTSSe film with uniform morphology and favorable defect properties. The CZTSSe solar cells based on the hybrid grain-growth mechanism achieved the best efficiency of 12.6%. The investigation in this paper would provide new solutions for the crystallization regulation on CZTSSe photovoltaic material.
研究领域:
材料科学
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光伏技术
·
半导体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）