Scientific Reports
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2014
·Vol. 4
·期 1
·1-9
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IF 5.078
Zhong Jie,Xia Zhe,Luo Miao,Zhao Juan,Chen Jie,Wang Liang,Liu Xinsheng,Xue Ding-Jiang,Cheng Yi-Bing,Song Haisheng,Tang Jiang
To obtain high photovoltaic performances for the emerging copper zinc tin sulfide/selenide (CZTSSe) thin film solar cells, much effort has deservedly been placed on CZTSSe phase purification and CZTSSe grain size enhancement. Another highly crucial but less explored factor for device performance is the elemental constitution of CZTSSe surface, which is at the heart of p-n junction where major photogenerated carriers generate and separate. In this work we demonstrate that, despite the well-built phase and large grained films are observed by common phases and morphology characterization (XRD, Raman and SEM), prominent device efficiency variations from short circuited to 6.4% are obtained. Insight study highlights that the surface (0–250 nm) compositions variation results in different bulk defect depths and doping densities in the depletion zone. We propose that suitable sulfurization (at ~10 kPa sulfur pressure) drives optimization of surface constitution by managing the Cu, Zn and Sn diffusion and surface reaction. Therefore, our study reveals that the balance of elemental diffusion and interface reactions is the key to tuning the surface quality CZTSSe film and thus the performance of as resulted devices.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
·
2016
·
IF 9.407
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%).
研究领域:
材料科学
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光伏技术
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半导体物理
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2018
·
IF 8.097
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.
研究领域:
材料科学
·
能源科学
·
薄膜技术
✓ 已验证
产品关联
DOI
PubMed
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
SOLAR ENERGY MATERIALS AND SOLAR CELLS
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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
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半导体物理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 16
·5498-5504
·
IF 6.4
Haoyu Xu,Xuanyang Guo,Hui Yang,Qing Zhou,Shiyan Liu,Haifeng Gao,Chao Gao,Wei Yu
In this study, Cu2ZnSn(S,Se)4 (CZTSSe) films were prepared by a non-vacuum solution method. The efficiency of an as-fabricated CZTSSe solar cell was improved from 8.0% to 10.9% by adding NaTFSI (sodium bis(trifluoromethanesulfonyl)imide) in the precursor solution. It was found that the NaTFSI additive could facilitate the formation and grain-growth of CZTSSe during the selenization of the film. As a result, the size of the crystalline grains in the CZTSSe films increased. Besides, a shallow level acceptor rather than a deep level acceptor could be generated in the CZTSSe films by using the NaTFSI additive. The use of NaTFSI could also decrease the relative content of the low valence Sn2+, which was believed to be related with deep level defects in CZTSSe. In addition, the effect of the NaTFSI concentration on the properties of CZTSSe solar cells were investigated. We found that excess NaTFSI in the precursor solution would not influence the recombination of the carriers in the neutral region of the solar cell, but could enhance the recombination of the carriers in the depletion region of the solar cell. Therefore, the performances of CZTSSe solar cells were reduced when excess NaTFSI was added in the precursor solution.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
IF 6.371
Qing Zhou,Meinan Yan,Yuzhou Sun,Yujiao Ma,Zihan Zhang,Haoyu Xu,Xiaoyun Teng,Chao Gao,Wei Yu
In this paper, we reported a novel precursor solution for the preparation of Cu 2 ZnSn(S,Se) 4 (CZTSSe) film. Large-grain monolayer CZTSSe film can be obtained by using the precursor solution. The influence of selenization temperature on the properties of CZTSSe films and solar cells were investigated. We found the monolayer CZTSSe film can be prepared with the selenization temperature as low as 510 °C. While an increased selenization temperature was used, the size of the crystalline grains in CZTSSe film increased significantly, but the decomposition of CZTSSe material got more serious. As the increase of the selenization temperature, increased short-circuit current (J SC ) can be achieved for the fabricated solar cell, which could be caused by the improved crystallinity of CZTSSe layer and the enlarged depletion width of solar cell (as much as 391 nm). On the other hand, the open-circuit voltage (V OC) decreased as the increase of selenization temperature, which may relate with the decomposition of CZTSSe material. The best solar cell achieved the efficiency of 11.4% (active area), which was based on CZTSSe film with the selenization temperature of 510 °C.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2019
·
IF 5.162
Biwen Duan,Linbao Guo,Qing Yu,Jiangjian Shi,Huijue Wu,Yanhong Luo,Dongmei Li,Sixin Wu,Zhi Zheng,Qingbo Meng
In CZTSSe solar cells, a simple sodium-incorporation post-treatment method toward solution-processed Cu 2 ZnSnS 4 precursor films is presented in this work. An ultrathin NaCl film is deposited on Cu 2 ZnSnS 4 precursor films by spin-coating NaCl solution. In subsequent selenization process, the introduction of NaCl is found to be benefacial for the formation of Cu 2- x Se, which can further facilitate the element transportation, leading to dense and smooth CZTSSe films with large grains and less impurity Cu 2 Sn(S,Se) 3 phase. SIMS depth profiles confirm the gradient distribution of the sodium element in Na-doped absorbers. Photoluminescence spectra show that the introduction of appropriate sodium into the absorber can inhibit the band tail states. As high as 11.18% of power conversion efficiency (PCE) is achieved for the device treated with 5 mg mL −1 NaCl solution, and an average efficiency of Na-doped devices is 10.71%, 13% higher than that of the control groups (9.45%). Besides, the depletion width and the charge recombination lifetime can also have regular variation with sodium treatment. This work offers an easy modification method for high-quality Na-doped CZTSSe films and high-performance devices, in the meantime, it can also help to further understand the effects of sodium in CZTSSe solar cells.
研究领域:
材料科学
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太阳能电池技术
✓ 已验证
产品关联
DOI
高影响因子
AIP Advances
·
2021
·Vol. 11
·期 7
·
IF 1.548
Lv Xiaogong,Zhu Chengjun,Yang Yanchun,Liu Ruijian,Fan Wenliang,Wang Yiming
In this work, Cu 2 ZnSnS 4 (CZTS) precursor films were deposited using a water-based solution approach. Subsequently, selenization was performed at different temperatures in the range of 480–610 °C to prepare Cu 2 ZnSn(S,Se) 4 (CZTSSe) absorber-layer films. The effects of the selenization temperature on the crystallinity, structure, morphology, and photoelectric properties of CZTSSe thin films, as well as the performance of solar cells constructed using these films, were systematically studied. The absorber-layer films selenized at different temperatures all formed pure-phase CZTSSe and had basically the same film thickness. It was found that application of an optimal selenization temperature can enhance the crystallinity, crystal grain size, and mobility and reduce the resistivity of CZTSSe films. Selenization at 550 °C resulted in the largest grain size (∼ μ m), the highest crystallinity, the highest mobility (4.29 cm 2 V −1 s −1 ), the lowest resistivity (3.13 × 10 2 Ω cm), the thinner fine-grained layer, a bandgap value of 1.21 eV, and a Cu-poor, Zn-rich elemental composition [Cu/(Zn + Sn) = 0.85 and Zn/Sn = 1.16]. The power-conversion efficiency was improved from 3.04% in a CZTSSe cell device with an absorber layer selenized at 480 °C to 4.69% in a film selenized at 550 °C. This was mainly due to the improvement of the crystallinity, crystal grain growth, and reduction of the fine-grained layer of the CZTSSe film. These results show that optimizing the selenization temperature is essential for enhancing the performance and the ultimate device efficiency of CZTSSe absorber layers prepared using a water-based solution approach.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
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
JOURNAL OF ELECTRONIC MATERIALS
·
2023
·Vol. 52
·期 8
·5422-5429
·
IF 2.1
Xu Jiaxiong,Wu Xiaoshuai
Chalcogenide Cu 2 ZnSn(S,Se) 4 (CZTSSe) is a promising absorber material for photovoltaic applications. When CZTSSe thin film is deposited on an Mo substrate, a Mo(S,Se) 2 layer easily forms between the CZTSSe and the Mo, which is detrimental to the back contact property of the CZTSSe. This work proposes a useful way to inhibit the formation of Mo(S,Se) 2 by sputtering a CuCrO 2 layer on a Mo-foil substrate before the deposition of the CZTSSe. The effects of CuCrO 2 thickness on the crystalline structures, morphologies, and electrical properties of the fabricated samples were studied. The results showed that the insertion of the CuCrO 2 layer prevented the formation of Mo(S,Se) 2 . As the thickness of the CuCrO 2 increased, the thickness of the Mo(S,Se) 2 layer decreased. The Mo(S,Se) 2 layer was absent from the cross-sectional scanning electron microscopy image when the CuCrO 2 thickness exceeded 85 nm. The back contact resistance of CZTSSe decreased monotonously as the CuCrO 2 layer thickened due to the reduction in the Mo(S,Se) 2 layer thickness. Therefore, by inserting a CuCrO 2 layer to separate the CZTSSe and the Mo-foil, the formation of the Mo(S,Se) 2 layer between them was effectively suppressed, and the back contact properties of the CZTSSe thin film were significantly enhanced.
研究领域:
材料科学
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光伏技术
·
薄膜太阳能电池
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2016
·
IF 4.732
Jing Guo,Wen-Hui Zhou,Ying-Li Pei,Qing-Wen Tian,Dong-Xing Kou,Zheng-Ji Zhou,Yue-Na Meng,Si-Xin Wu
CZTSSe based thin film solar cells have received considerable interests due to low material cost, suitable band gaps and high absorption coefficient of CZTSSe materials. Achieving high efficiency CZTSSe based thin film solar cells often need a high temperature selenization process that always causes Sn loss in the form of gaseous SnSe 2 . Additional Sn complement may decrease the loss of Sn during selenization process and improve the performance of fabricated CZTSSe based thin film solar cells. Here, we investigate the effect of additional Sn complement on the performance of CZTSSe based thin film solar cells fabricated from pure element solution. XRD and Raman characterizations indicate that additional Sn complement could reduce the secondary phase that may cause the voltage loss and decrease of efficiency. The solar cell fabricated with 15% additional Sn complement shows the best conversion efficiency of 8.71% (V OC =0.42 V, J SC =32.73 mA cm −2 , FF=63.19%). To the best of our knowledge, it is the highest efficiency of CZTSSe based thin film solar cells fabricated from pure element solution.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）