Photoelectrochemical performance of Zn-doped n-type CuInS2 thin film prepared by spray pyrolysis method

• Main Authors: Kai-Chun Yang, 楊凱鈞
• Other Authors: Tai-Chou Lee
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/81122088556971001614

碩士 === 國立中央大學 === 化學工程與材料工程學系 === 105 === n-type CuInS2 thin films were fabricated with different [Cu]/[In] ratio in precursor by spray pyrolysis method on a transparent indium-doped tin oxide (ITO) substrate followed by calcination in the Ar at 500 oC. Further we investigated the structural and optical properties of Zn-doped n-type CuInS2. As the XRD patterns, shows the chalcopyrite CuInS2 structure with the increase of the amount of Cu, the higher the crystallinity of CuInS2. The optical study show the absorption coefficient (α) in the UV-visible region is found to be in the order of 104~105 cm-1 which is the optimum value for an efficient absorber. The synthesized n-type CuInS2 thin film has an optical bandgap of 1.5~1.55 eV. CuInS2 thin film yielded a photocurrent density of 2.24 mA cm-2 at 1.23 V vs. RHE in 0.25 M Na2S and 0.35 M Na2SO3 under 300 W xenon lamp. Zn-doped CuInS2 has the same optical bandgap of 1.5~1.6 eV as the n-type CuInS2. Zn-doped CuInS2 didn’t facilitate photocurrent density, but photocurrent density didn’t drop too much as well. For this characteristic, we will determine energy band position of n-type CuInS2 and Zn-doped CuInS2 to be band position design of the p-n junction material.