The study on producing copper-zinc-tin-sulfur (Cu2ZnSnS4, CZTS) powders by using high pressure hydrothermal method

• Main Authors: Zih-Chun Dai, 戴子淳
• Other Authors: King-Leung Wong
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/99194965302175929705

碩士 === 崑山科技大學 === 機械工程研究所 === 100 === Owing to the limited hidden volume of In and Ga material which are used to fabricate the CIGS, the shortage of those materials may occur. Meanwhile, H2Se used in selenide process (one of CIGS processes) is toxic gas. Therefore, in recent years there are some alternative absorption layer materials substituting CIGS, such as copper-zinc-tin-sulfur compounds (Cu2ZnSnS4, referred to CZTS), copper-zinc-tin-selenium compounds (Cu2ZnSnSe4, referred to CZTSe) and other like quaternary compound semiconductors in the chalcopyrite structure. In this study, high pressure hydrothermal method is used to produce Cu2ZnSnS4 (CZTS) powder. From the different conditions for different species of reactants, reaction time of the high-pressure hydrothermal method and the reactant concentration, the optimal synthesis conditions can be found out. The characteristics of prepared powders are analyzed by XRD, SEM, UV-Vis analysis. Metal elements of Cu2ZnSnS4 are obtained from the reactive species CuCl, CuCl2, SnCl2.2H2O, SnSO4.2H2O and ZnCl2. And the sulfur element is obtained from thiourea. In this study, the most appropriate synthesis reactants CuCl, SnCl2.2H2O, ZnCl2, and thiourea are adopted. The suitable high-pressure hydrothermal reaction time is found out from experiments should be more than 48 hours, the binary phase or ternary phase product formation then can be reduced. In order to avoid the complexes are produced in the thiourea and copper ions in the reaction solution, thiourea concentration should be four times greater than copper ions. The single crystal phase of Cu2ZnSnS4 powder with about 1.45eV energy gap in accordance with the JCPDS Card can be obtained from the above conditions.