This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentr...This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentrations of absorber-layer material and operating temperature. Our aims focused to identify the most optimal thin-film solar cell structure that offers high efficiency and lower toxicity which are desirable for sustainable and eco-friendly energy sources globally. SCAPS-1D, widely used software for modeling and simulating solar cells, has been used and solar cell fundamental performance parameters such as open-circuited voltage (), short-circuited current density (), fill-factor() and efficiency() have been optimized in this study. Based on our simulation results, it was found that CZTS solar cell with Cd<sub>0.4</sub>Zn<sub>0.6</sub>S as buffer-layer offers the most optimal combination of high efficiency and lower toxicity in comparison to other structure investigated in our study. Although the efficiency of Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS are comparable, Cd<sub>0.4</sub>Zn<sub>0.6</sub>S is preferable to use as buffer-layer for its non-toxic property. In addition, evaluation of performance as a function of buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS showed that optimum buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S was in the range from 50 to 150nm while ZnS offered only 50 – 75 nm. Furthermore, the temperature dependence performance parameters evaluation revealed that it is better to operate solar cell at temperature 290K for stable operation with optimum performances. This study would provide valuable insights into design and optimization of nanotechnology-based solar energy technology for minimizing global energy crisis and developing eco-friendly energy sources sustainable and simultaneously.展开更多
The low temperature phase transformation in the Cu_2ZnSnS_4(CZTS) films was investigated by laser annealing and low temperature thermal annealing.The Raman measurements show that a-high-power laser annealing could c...The low temperature phase transformation in the Cu_2ZnSnS_4(CZTS) films was investigated by laser annealing and low temperature thermal annealing.The Raman measurements show that a-high-power laser annealing could cause a red shift of the Raman scattering peaks of the kesterite(KS) structure and promotes the formation of the partially disordered kesterite(PD-KS) structure in the CZTS films,and the low-temperature thermal annealing only shifts the Raman scattering peak of KS phase by several wavenumber to low frequency and the broads Raman peaks in the low frequency region.Moreover,the above two processes were reversible.The Raman analyses of the CZTS samples prepared under different process show that the PD-KS structure tends to be found at low temperatures and low sulfur vapor pressures.Our results reveal that the control of the phase structure in CZTS films is feasible by adjusting the preparation process of the films.展开更多
Electrodeposition of CZTS thin films on ZnS was carried using a 2-electrode method to fabricate superstrate structure solar cells. A comprehensive study was performed on the effects of trisodium citrate on the CZTS el...Electrodeposition of CZTS thin films on ZnS was carried using a 2-electrode method to fabricate superstrate structure solar cells. A comprehensive study was performed on the effects of trisodium citrate on the CZTS electrolyte bath. In the present investigation, it is demonstrated that using a CZTS electrolyte with a concentration of 0.2 M trisodium citrate yields CZTS thin films with an electronic bandgap of 1.52 eV, a p-type nature, and good uniformity, which are all results desired for the fabrication of thin film solar cells. Characterization was performed using UV-Vi-IR optical absorption, SEM imaging, Raman spectrometry, and photoelectrochemical cells conducted for electronic bandgap, morphology, chemical composition, and semiconductor conductivity, respectively.展开更多
采用磁控溅射后硫化的方法制备Cu_2ZnSnS_4(CZTS)薄膜,分别用Zn和Zn S作为锌源,在镀钼的钠钙玻璃衬底上以Zn(或Zn S)/Sn/Cu的顺序制备出不同的CZTS薄膜预制层。首先对预制层进行低温合金,然后以硫粉作为硫源进行高温硫化,得到CZTS薄膜...采用磁控溅射后硫化的方法制备Cu_2ZnSnS_4(CZTS)薄膜,分别用Zn和Zn S作为锌源,在镀钼的钠钙玻璃衬底上以Zn(或Zn S)/Sn/Cu的顺序制备出不同的CZTS薄膜预制层。首先对预制层进行低温合金,然后以硫粉作为硫源进行高温硫化,得到CZTS薄膜。通过X射线衍射仪(XRD)、扫描电镜(SEM)及能谱仪(EDS)分别对所制备薄膜的晶体结构、表面形貌和薄膜组分进行分析表征;并用拉曼光谱表征了CZTS相的纯度。最后用CZTS薄膜制备了太阳电池,发现在预制层中以Zn S作为锌源得到的太阳电池有较高的性能参数,其开路电压:Voc=651 m V,短路电流密度:Jsc=11.4 m A/cm2,光电转换效率达到2.8%。展开更多
Zn/Sn/Cu (CZT) stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures (200℃, 300 ℃, 350 ℃, and 400 ℃) for 0.5 h and then followed by sulfurization at 500℃ for ...Zn/Sn/Cu (CZT) stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures (200℃, 300 ℃, 350 ℃, and 400 ℃) for 0.5 h and then followed by sulfurization at 500℃ for 2 h. Then, the structures, morphologies, and optical properties of the as-obtained Cu2ZnSnS4 (CZTS) films were studied by x-ray diffraction (XRD), Raman spectroscopy, UV-Vis-NIR, scanning electron microscope (SEM), and energy-dispersive x-ray spectroscopy (EDX). The XRD and Raman spectroscopy results indicated that the sample pretreated at 350℃ had no secondary phase and good crystallization. At the same time, SEM confirmed that it had large and dense grains. According to the UV-Vis-NIR spectrum, the sample had an absorption coefficient larger than 10^4 cm-1 in the visible light range and a band gap close to 1.5 eV.展开更多
文摘This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentrations of absorber-layer material and operating temperature. Our aims focused to identify the most optimal thin-film solar cell structure that offers high efficiency and lower toxicity which are desirable for sustainable and eco-friendly energy sources globally. SCAPS-1D, widely used software for modeling and simulating solar cells, has been used and solar cell fundamental performance parameters such as open-circuited voltage (), short-circuited current density (), fill-factor() and efficiency() have been optimized in this study. Based on our simulation results, it was found that CZTS solar cell with Cd<sub>0.4</sub>Zn<sub>0.6</sub>S as buffer-layer offers the most optimal combination of high efficiency and lower toxicity in comparison to other structure investigated in our study. Although the efficiency of Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS are comparable, Cd<sub>0.4</sub>Zn<sub>0.6</sub>S is preferable to use as buffer-layer for its non-toxic property. In addition, evaluation of performance as a function of buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS showed that optimum buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S was in the range from 50 to 150nm while ZnS offered only 50 – 75 nm. Furthermore, the temperature dependence performance parameters evaluation revealed that it is better to operate solar cell at temperature 290K for stable operation with optimum performances. This study would provide valuable insights into design and optimization of nanotechnology-based solar energy technology for minimizing global energy crisis and developing eco-friendly energy sources sustainable and simultaneously.
基金Project supported by the Natural Science Foundation for Youth Fund of Hebei Province,China(Grant No.A2016201087)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20131301120003)the National Natural Science Foundation of China(Grant Nos.11504078and 61504054)
文摘The low temperature phase transformation in the Cu_2ZnSnS_4(CZTS) films was investigated by laser annealing and low temperature thermal annealing.The Raman measurements show that a-high-power laser annealing could cause a red shift of the Raman scattering peaks of the kesterite(KS) structure and promotes the formation of the partially disordered kesterite(PD-KS) structure in the CZTS films,and the low-temperature thermal annealing only shifts the Raman scattering peak of KS phase by several wavenumber to low frequency and the broads Raman peaks in the low frequency region.Moreover,the above two processes were reversible.The Raman analyses of the CZTS samples prepared under different process show that the PD-KS structure tends to be found at low temperatures and low sulfur vapor pressures.Our results reveal that the control of the phase structure in CZTS films is feasible by adjusting the preparation process of the films.
文摘Electrodeposition of CZTS thin films on ZnS was carried using a 2-electrode method to fabricate superstrate structure solar cells. A comprehensive study was performed on the effects of trisodium citrate on the CZTS electrolyte bath. In the present investigation, it is demonstrated that using a CZTS electrolyte with a concentration of 0.2 M trisodium citrate yields CZTS thin films with an electronic bandgap of 1.52 eV, a p-type nature, and good uniformity, which are all results desired for the fabrication of thin film solar cells. Characterization was performed using UV-Vi-IR optical absorption, SEM imaging, Raman spectrometry, and photoelectrochemical cells conducted for electronic bandgap, morphology, chemical composition, and semiconductor conductivity, respectively.
文摘采用磁控溅射后硫化的方法制备Cu_2ZnSnS_4(CZTS)薄膜,分别用Zn和Zn S作为锌源,在镀钼的钠钙玻璃衬底上以Zn(或Zn S)/Sn/Cu的顺序制备出不同的CZTS薄膜预制层。首先对预制层进行低温合金,然后以硫粉作为硫源进行高温硫化,得到CZTS薄膜。通过X射线衍射仪(XRD)、扫描电镜(SEM)及能谱仪(EDS)分别对所制备薄膜的晶体结构、表面形貌和薄膜组分进行分析表征;并用拉曼光谱表征了CZTS相的纯度。最后用CZTS薄膜制备了太阳电池,发现在预制层中以Zn S作为锌源得到的太阳电池有较高的性能参数,其开路电压:Voc=651 m V,短路电流密度:Jsc=11.4 m A/cm2,光电转换效率达到2.8%。
基金supported by Funding for Outstanding Doctoral Dissertation in NUAA,China(Grant No.BCXJ13-12)the Jiangsu Innovation Program for Graduate Education,China(Grant No.CXLX13 150)+2 种基金the Fundamental Research Funds for the Central Universities,China(Grant No.61176062)the Science and Technology Supporting Project of Jiangsu Province,China(Grant No.BE2012103)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Zn/Sn/Cu (CZT) stacks were prepared by RF magnetron sputtering. The stacks were pretreated at different tem- peratures (200℃, 300 ℃, 350 ℃, and 400 ℃) for 0.5 h and then followed by sulfurization at 500℃ for 2 h. Then, the structures, morphologies, and optical properties of the as-obtained Cu2ZnSnS4 (CZTS) films were studied by x-ray diffraction (XRD), Raman spectroscopy, UV-Vis-NIR, scanning electron microscope (SEM), and energy-dispersive x-ray spectroscopy (EDX). The XRD and Raman spectroscopy results indicated that the sample pretreated at 350℃ had no secondary phase and good crystallization. At the same time, SEM confirmed that it had large and dense grains. According to the UV-Vis-NIR spectrum, the sample had an absorption coefficient larger than 10^4 cm-1 in the visible light range and a band gap close to 1.5 eV.