本研究利用噴塗法，改變不同[Cu]/[In]比例之前驅物濃度，在S 充 足的情況下，沉積在ITO 導電玻璃上，之後經由熱處理500 oC 製備 出n-type CuInS2 薄膜，並且摻雜不同濃度之Zn，希望能提升光電流 表現及調整能階位置來做為p-n junction 能階設計的材料。結構分析 顯示為正方晶系黃銅礦結構的CuInS2，且隨著Cu 的量增加，結晶性 越高，另外無雜相的生成。在紫外光可見光波段，吸收係數大約在104 ~ 105 之間，是很理想的光吸收材料，而各比例之能隙值變化不大，大 約介於1.5 ~ 1.55 eV 之間。而光電化學性質中，在電壓= 1.23 V vs. RHE 時，電解質為犧牲試劑的情況下，n 型光電流表現能達到2.24 mA/cm2。n-type CuInS2 摻雜Zn 後，由XRD 觀察結晶相並沒有改變， 也無雜相生成。在光電流表現上，沒有達到提升光電流的效果。由UVvis 分析，隨著Zn 摻雜量的上升，能隙值有稍微變大的趨勢，不過能 隙值都位在1.5~1.6 eV 之間。摻雜Zn 後光電流表現並沒有下降特別 多，可以利用此特性，我們會進一步量測能階位置來判斷摻雜n-type CuInS2 及Zn 之n-type CuInS2 是否能做為p-n junction 能階設計的材 料之一。;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.
