OPTICAL MATERIALS
·
2020
·
IF 2.779
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.
研究领域:
材料科学
·
半导体物理
·
薄膜制备
·
光伏材料
·
固体化学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2022
·Vol. 51
·期 45
·17328-17337
·
IF 4.569
Yan Zhu,Hongmei Qing,Wenbo Dong,Mingrong Dong,Tao Shen,Jian Cui
Copper zinc tin sulfide (Cu2ZnSnS4, CZTS) is attracting interest in photovoltaic applications due to its proper band gap, low cost and low toxicity. It has been found that two phases can be fabricated, i.e. kesterite and wurtzite CZTS structures. Though kesterite CZTS is proven to be thermodynamically stable, the free energy difference between kesterite and wurtzite CZTS is rather small. So, wurtzite CZTS can also stably exist under ambient conditions. Controlling the phase formation can expand the dimensions to optimize the performance of applications based on CZTS. In this study, we found that phase control can be achieved by simply using a mixed solvent of ethylene glycol and triethylenetetramine (TETA) in a two-stage heating process. It is found that the incorporation of the reductive solvent of TETA during the 1st heating process converts the phase of the precipitates from CuS (TETA poor) to Cu7S4 (TETA rich). In the subsequent 2nd heating stage, the phase of the final products is determined to be kesterite CZTS originating from CuS and wurtzite CZTS from Cu7S4, respectively. Thus, the key to control the phases of the final products is to control the chemical environment of Cu under Cu1+-rich or Cu2+-rich conditions in the fabrication process, which corresponds to the phase of the final products of wurtzite CZTS or kesterite CZTS, respectively. This summarized principle can not only be used to explain the previous versatile experimental results but also to guide the controlled synthesis of various phases of CZTS and CZTS-like materials in applications.
研究领域:
材料科学
·
无机化学
·
半导体材料
·
纳米科技
·
光伏材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Hui Chen,Jinfeng Wang,Chenchen Jia,Junpeng Mou,Lei Zhu
For the purpose of increasing the power conversion efficiency (PCE) meanwhile decreasing the cost of dye-sensitized solar cell (DSSC), Cu 2 ZnSnS 4 - multiwall carbon nanotubes (CZTS-MWCNTs) nanohybrid Pt-free counter electrode (CE) was prepared via a facile fabricating route. In brief, CZTS nanoparticles were synthesized by a solvothermal method and the composite film was fabricated by spin coating the aqueous solution of the composite. The short-circuit current density and PCE of the DSSC with CZTS-MWCNTs CE were found to be 16.62 mA cm −2 and 9.04%, respectively. But the corresponding values were 15.42 mA cm −2 and 8.74% for a DSSC with a pure Pt-CE. This is owing to the synergistic effect of the intrinsic superior electrocatalytic activity of the CZTS nanoparticles and highly specific surface area and high electrical conductivity of the MWCNTs . The presence and distribution of CZTS-MWCNTs on the CE were characterized by X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), respectively. Cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were examined for confirming the high electrocatalytic efficiency of this nanohybrid system.
研究领域:
材料科学
·
能源化学
·
纳米技术
·
电化学
·
光伏器件
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
·
IF 6.333
Yanchun Yang,Xiaojiao Kang,Lijian Huang,Song Wei,Daocheng Pan
Earth abundant Cu 2 ZnSn(S,Se) 4 (CZTSSe) has been considered as one of the most promising thin film solar cell absorber candidates. Here, we develop a facile water-based precursor solution approach for depositing high-efficiency Cu 2 ZnSn(S,Se) 4 thin film solar cells. In this environmentally friendly approach, inexpensive elemental Cu, Zn, Sn and S powders are used as the starting materials and are dissolved in the aqueous solution of thioglycolic acid and methylamine, forming a homogeneous precursor solution for depositing Cu 2 ZnSnS 4 nanocrystal thin film . As-deposited CZTS nanocrystal thin films are selenized to form the large-grain CZTSSe absorber layers . It was found that Na doping plays an important role in the formation of the extremely dense and flat CZTSSe absorber layer, and fill factor can be significantly improved for Na-doped CZTSSe solar cells, which lead to a photoelectric conversion efficiency of 6.96% with an open-circuit voltage of 378 mV, a short current density of 28.17 mA cm −2 , and a fill factor of 65.4%.
研究领域:
材料科学
·
新能源材料
·
半导体薄膜
·
光伏技术
·
无机功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）