电解液pH值对电化学法制备的CIGS薄膜光电性能的影响

Influence of pH Value in Electrolyte on Photovoltaic Performance of CIGS Thin-films Prepared by Electrochemical Method

以F掺杂透明导电玻璃(FTO)为基底,利用一步电化学沉积法制备了Cu(In1-x,Gax)Se2(CIGS)薄膜,系统地研究了电解液pH值对CIGS薄膜的化学组分、结构及其光电性能的影响。结果显示通过改变电解液pH值可以有效调控薄膜中In和Ga的化学计量比。X射线衍射(XRD)分析和扫描电子显微镜(SEM)结果表明,pH值为2.0时制备的CIGS薄膜结晶性较好,颗粒尺寸分布均匀。并且利用表面光伏技术研究了不同化学计量比对CIGS薄膜中光电荷动力学过程的影响,结果表明n(Ga)/n(In+Ga)约为0.3时,CIGS薄膜的光电性能最好。

Cu（In1-x,Gax）Se2 （CIGS） films were prepared by one-step electrodeposition method on FTO glass substrates, and the influence of electrolytic pH on the chemical composition, structure and photovoltaic performance of CIGS thin-films were studied in detail. The results showed that the stoichiometry of In and Ga in the film could be effectively regulated by changing the pH value of the electrolyte. The X-ray diffraction （XRD） analysis and scanning electron microscopy （SEM） results showed that the CIGS thin-films had good crystallinity and uniform particle size distribution when the pH value was 2.0. The effect of different stoichiometries of the CIGS thin-films on the kinetics of photo-charges was also studied. The CIGS thin film with a stoichiometric ratio of 0.3 for Ga/（In ＋ Ga） presented the strongest surface photovoltaic effect.