查找使用阿拉丁产品的科研文献

Enhancing the efficiency of Cu2ZnSn(S,Se)4 solar cells by variable-temperature sulfoselenization

Yonggang Zhao,Congyan Xu,Zhineng Zhou,Yufei Chen,Ying Zhang,Lang Wu,Xu Su,Xinghuan Hu,Shurong Wang

High-temperature sulfoselenization is essential in producing Cu2ZnSn (S,Se)4 (CZTSSe) thin-film solar cells. At high temperature, the Cu2ZnSn(S,Se)4 phase-transition speed is fast, which causes grain transition to mature quickly, followed by grain decomposition. Although grain surfaces are relatively flat at low temperatures, the small grain and more grain boundaries lead to low efficiency. In this study, a dynamic-temperature sulfoselenization process was adopted to utilize both the advantages of high and low temperatures comprehensively. Different constant- and variable-temperature sulfoselenization processes were developed for annealing Cu–Zn–Sn–S precursor films prepared in the air using dimethyl sulfoxide (DMSO) and 2-methoxyethanol (MOE) dual solvent systems. As a result, CZTSSe films with a flat, holeless, and dense surface, and a single-layer large grain penetrating the whole cross-section were fabricated by a proper variable-temperature sulfoselenization process. Finally, 11.11% total-area power conversion efficiency (12.22% active area efficiency) of CZTSSe solar cells (without antireflection coating) based on the variable-temperature sulfoselenization process was achieved successfully. Compared with the highest efficiency of 9.10% of CZTSSe film solar cells fabricated from the stable-temperature sulfoselenization annealing process, the efficiency was improved by 22%. The variable-temperature annealing processes in this study can also be applied to the preparation of other multi-element thin-film semiconductor materials.

Phase-Separation-Induced Crystal Growth for Large-Grained Cu2ZnSn(S,Se)4 Thin Film

Lijian Huang,Song Wei,Daocheng Pan

Large-grained Cu2ZnSn(S,Se)4 (CZTSSe) absorber layers are highly desirable for high-performance CZTSSe thin film solar cells. However, solution-deposited CZTSSe thin films usually consist of a large-grained top layer and a smaller-grained bottom layer. In this work, we adopt a phase-separation strategy to promote the crystal growth of the CZTSSe thin film. By choosing ZnCl2, SnCl2, CuCl (instead of CuCl2), and thiourea as the starting materials, a Cu2S/SnS/ZnS hybrid precursor thin film can be prepared, the composition of which has been testified by X-ray diffraction, X-ray photoelectron spectroscopy, Raman, and scanning electron microscopy-energy-dispersive spectrometry characterization. Owing to the volume expansion caused by Se incorporation and the high migration abilities of Cu(I) and Sn(II) ions during selenization, large-grained and compact CZTSSe films with a thickness up to 5 μm can be obtained. The corresponding thin film solar cell devices have achieved active power conversion efficiencies above 10% (8.78% for total area), much higher than those of CuCl2-based CZTSSe devices in our lab.

Above 10% efficient electrodeposited Cu2ZnSn(S,Se)4 solar cell achieved by modifying precursor

Xiatong Qin,Bin Xu,Jianjun Lin,Jiaqi Chen,Hanyu Tong,Ye Chen,Pingxiong Yang,Junhao Chu,Lin Sun

Electrodeposition is a promising method to fabricate Cu 2 ZnSn(S,Se) 4 (i.e., CZTSSe) absorber layer thanks to its many advantages such as low-cost and large-scale. However, the secondary phases and intrinsic defects in electrodeposited CZTSSe solar cells inevitably limit the photoelectric performance. Herein, two different kind of precursor films (binary-ternary selenide vs. quaternary selenide) are deliberately fabricated and the effect of these precursors on the secondary phases and intrinsic defects of CZTSSe absorber layer are investigated comprehensively. The absorber layer obtained from binary-ternary selenide precursor has a small amount of ZnSe secondary phases and Cu Sn deep defects , whereas that obtained from the quaternary selenide precursor exhibits the favorable V Cu shallow defects, which is beneficial to the efficiency improvement in CZTSSe. Based on the quaternary selenide precursor film, the CZTSSe solar cell with 10.03% total area efficiency (the active area efficiency is 10.9%) was obtained. This is the highest efficiency of CZTSSe solar cells prepared by the electrodeposition method.

MoO2 Sacrificial Layer for Optimizing Back Contact Interface of Cu2ZnSn(S,Se)4 Solar Cells

Bin Xu,Xiaoshuang Lu,Chuanhe Ma,Yulin Liu,Ruijuan Qi,Rong Huang,Ye Chen,Pingxiong Yang,Junhao Chu,Lin Sun

Efficient flexible Mo foil-based Cu2ZnSn(S, Se)4 solar cells from In-doping technique

Xue Yu,Shuying Cheng,Qiong Yan,Junjie Fu,Hongjie Jia,Quanzhen Sun,Zhiyuan Yang,Sixin Wu

Cation substitution has an important impact on the power conversion efficiency (PCE) of Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells. Herein, a significant PCE enhancement of flexible indium-doped CZTSSe solar cells has been achieved by partially substituting Sn 4+ with In 3+ . Systematic measurements indicate that In doping in CZTSSe film effectively improves the crystallinity and carrier concentration of the absorber layer . Meanwhile, the treatment reduces interface recombination and band tailing by passivating deep defects and increases the open-circuit voltage ( V oc ) of the solar cells. By physical analysis, the key parameters for the solar cell diode such as A , J 0 , R s and R sh are significantly improved after In-doping, indicating better PN junction quality. Under the optimal In-doping (x = In/(Sn + In) = 9%), the flexible Cu 2 ZnSn 1- x In x (S,Se) 4 solar cell has been successfully obtained with the best efficiency of 7.19% and the V oc enhancement of 62 mV due to reduced V oc deficit and band tailing.

Optimizing the window layer for achieving over 10% efficient Cu2ZnSn(S,Se)4 solar cells

Yu He,Chenxi Zhao,Zecheng Lu,Ning Guo,Hongmei Luan,Yanchun Yang,Ruijian Liu,Chengjun Zhu

Indium tin oxide (ITO) and intrinsic ZnO (i-ZnO) are usually used as the window layer of Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells within a typical structure. The optoelectronic properties of the window layer play a crucial role in determining the efficiency of solar cells. In this work, two types of CZTSSe solar cells with and without i-ZnO layers were fabricated using dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) as solvents, respectively. The impact of the window layer on the performance of CZTSSe solar cells was investigated. The results suggest that the device without i-ZnO still exhibits a high power conversion efficiency (PCE) compared to conventional bilayer i-ZnO/ITO structures. By removing i-ZnO and optimizing the thickness of ITO, the highest power conversion efficiency (PCE) of DMSO and DMF-based CZTSSe solar cells has been up to 10.17% and 10.27%, respectively, with an increase in open-circuit voltage (V OC ) of 15 mV (in DMSO system) and 10 mV (in DMF system), as well as an enhancement in fill factor (FF) by ∼5 percentage points. These performance improvements are mainly attributed to the reduction of series resistance (R s ) of the window layer due to the removal of i-ZnO layer. Further analysis shows that the generation and collection of photon-generated carriers in CZTSSe solar cells can be affected by the optimized window layer due to optical interference effects and its resistance. Our research may provide insights for the preparation of high efficient CZTSSe solar cells with new structures of the i-ZnO free window layer.

Improving the Performance of Solution-Processed Cu2ZnSn(S,Se)4 Photovoltaic Materials by Cd2+ Substitution

Jie Fu,Qingwen Tian,Zhengji Zhou,Dongxing Kou,Yuena Meng,Wenhui Zhou,Sixin Wu

Additional elements in the Cu2ZnSn(S,Se)4 (CZTSSe) absorber layers can play a crucial role in improving the performance of thin film solar cells. In this paper, a significant performance enhancement of CZTSSe thin film solar cells was achieved by the partial substitution of the Zn2+ cation with Cd2+. A small amount of Cd2+ can be successfully incorporated into the host lattice of CZTSSe to form a homogeneous Cu2Zn1–xCdxSn(S,Se)4 (CZCTSSe) alloy material. We demonstrated that the crystal growth and the band gap of CZCTSSe thin films are affected by the Cd doping level. Additionally, the impact of Cd content on the space-charge density (Nc-v) and the depletion width (Wd) of CZCTSSe solar cells was systematically investigated. By this cation substitution approach, the power conversion efficiency of the solar cells based on the CZCTSSe absorber was successfully increased from 5.41 to 8.11% for the optimal composition (x = 5%).

Solution-processed kesterite solar module with 10.1% certified efficiency

Xiang Chunxu,Yuan Mingjun,Ding Chuan’an,Zheng Yuanyuan,Li Yize,Hu Xiaole,Zhang Jie,Li Xinyu,Ma Chengfeng,Wang Shaoying,Yan Weibo,Yang Chunlei,Huang Wei,Xin Hao

Solution processing has great advantages for emerging thin-film solar cells but remains a big challenge for multielemental inorganic films due to complicated phase evolution and grain growth during crystallization. Here we report the fabrication of uniform, large-area Cu 2 ZnSn(S,Se) 4 (CZTSSe) films and solar modules from solution. By tuning the thiourea/metal ratio to increase film porosity—thereby promoting more uniform vertical reaction and lateral grain growth—we improved the uniformity of CZTSSe films and achieved a single-cell efficiency of 13.4% and a solar module efficiency of 8.91%. We further optimized the module structure to reduce non-ideal contact and patterning-induced shunt and resistive losses, resulting in a champion CZTSSe module with a National Renewable Energy Laboratory-certified efficiency of 10.1%. This module also exhibits the lowest cell-to-module loss in open circuit voltage and current density among state-of-the-art emerging thin-film solar modules. Our work demonstrates the viability of solution processing to deposit uniform, large-area CZTSSe film and efficient solar modules, advancing the development of the technology.

Green Atmospheric Aqueous Solution Deposition for High Performance Cu2ZnSn(S,Se)4 Thin Film Solar Cells

Qingwen Tian,Haiyang Lu,Yachao Du,Junjie Fu,Xiangyun Zhao,Sixin Wu,Shengzhong (Frank) Liu

Environment-friendly process, low production cost, and simple operation are regarded as key factors for scalable kesterite photovoltaic applications. Herein a green ammonium thioglycolate (TGAm)-based aqueous solution route has been developed to deposit Cu 2 ZnSnS 4 films. It is found that sinstering in ambient air is as good as in argon, making the production process more affordable and reproducible. TGAm is more active than other alkylthiols with longer alkyl chains and has a strong coordination capability toward metal ions, which is a key factor in the dissolution of a series of metal oxides. Meanwhile, TGAm is widely used in biopharmaceuticals and hairspray, demonstrating good biological compatibility. Moreover, a low level of Ag doping can be successfully incorporated into the host lattice of the CZTSSe to form a homogeneous (Cu 1−x ,Ag x ) 2 ZnSn(S,Se) 4 (CAZTSSe) alloy material by this aqueous process. Benefiting from the effect of Ag doping, the initial power conversion efficiency is successfully enhanced from 5.86% ( x = 0) to 7.38% ( x = 2%).

Influence of extra trace Mn-doping on the properties of Cu2ZnSn(S,Se)4 absorber layer

Guonan Cui,Yanchun Yang,Ruilan Chen,Chengjun Zhu

Cations substitutions are known to make much significant contribution on achieving the high-quality kesterite Cu 2 ZnSn(S,Se) 4 thin films . And the optimal ratios of Mn, Ni and Co substitutions are reported to be ~0.05, belong to the low doping to reduce their defect density , which looks like to some extent the effect of Na doping. In this study, learning the research experience of alkali metal doping, we introduced the extra trace Mn 2+ ion into the precursor solution without affecting the compositions of other elements (i.e. Cu, Zn, and Sn), and the effect of trace addition on properties of the absorber layer was also studied. It was discovered that crystalline, electrical properties, and hole carrier concentration of Cu 2 ZnSn(S,Se) 4 thin films increased with an increase of Mn incorporation, and the best doping ratio of Mn/(Cu + Zn + Sn) was considered to be 0.03. In addition, the effect of extra trace Mn-doping on the film thickness and elemental compositions of Cu 2 ZnSn(S,Se) 4 absorber layer were studied in detail.

Fabrication of a Cu2ZnSn(S,Se)4 Photovoltaic Device by a Low-Toxicity Ethanol Solution Process

Gang Wang,Wangen Zhao,Yong Cui,Qingwen Tian,Shang Gao,Lijian Huang,Daocheng Pan

Homogeneous molecular precursor solutions are excellent choices for obtaining smooth absorber layers, and they offer the potential to significantly lower the manufacturing cost of solar cells. Here, we present a thermally degradable metal butyldithiocarbamate-based solution approach to fabricate Cu2ZnSn(S,Se)4 solar cells. Low-cost Cu2O, ZnO, and SnO were used as the starting materials and were dissolved in the ethanol solution of butyldithiocarbamic acid. By tuning the composition of the Cu2ZnSn(S,Se)4 thin film, a power conversion efficiency of 6.03% on the basis of the active area has been achieved.

Crown Ether-Assisted ZnO for Low-Cost and High-Efficiency Cu2ZnSn(S, Se)4 Solar Cells

Yingjun Zhou,Chuanhe Ma,Shulei Liang,Yujun Li,Hailong Wang

In Cu 2 ZnSn(S, Se) 4 (CZTSSe) solar cells, the conventional magnetron-sputtered ZnO (ZnO-SP) suffers from high cost, low efficiency, and interface damage. This study systematically compares sol–gel ZnO (ZnO-SG) and 18C6 crown ether-modified sol–gel ZnO (ZnO-SG-18C6) as interfacial layers. X-ray diffraction (XRD), scanning electron microscope (SEM), AFM, and X-ray photoelectron spectroscopy (XPS) show ZnO-SP has a uniform hexagonal wurtzite structure, whereas ZnO-SG displays an amorphous fibrous morphology with bright/dark striations. Both exhibit similar UV absorption peaks, but ZnO-SG shows broader absorption and double-exponential decay. Density–voltage ( J – V ) tests reveal that ZnO-SG-18C6 increases PCE from 8.5% to 10.6%, surpassing the 9.5% achieved with ZnO-SP. Electrochemical impedance spectroscopy (EIS) analysis shows that the ZnO-SG-18C6 layer reduces carrier recombination, with the charge transfer resistance ( R ct ) increasing by 30%. Transient photocurrent measurements further reveal that it enhances the photocurrent response, achieving a 1.8-fold increase in the peak, which rises to four times under a 70% high duty cycle.This work demonstrates ZnO-SG-18C6 as a low-cost, high-efficiency alternative to ZnO-SP in CZTSSe solar cells.