太阳电池用CuInSe_2薄膜的电化学可控沉积

采用恒电位电沉积法制备了CuInSe_2薄膜材料,通过循环伏安分析探讨了Cu~(2+)、In~(3+)和H_2SeO_3单独沉积和共沉积的电化学行为,并研究了沉积电位对薄膜化学计量组成、形貌和物相组成的影响规律。研究表明:柠檬酸根离子对Cu~(2+)和H_2SeO_3具有络合作用,而对In~(3+)的络合不明显。共沉积时,Cu最先还原,然后诱导Se的沉积,两者反应形成的铜硒化合物Cu_xSe又诱导In的欠电位沉积,并与之反应生成CuInSe_2。在阴极电位为-0.58～-0.90Vvs.SCE时出现了不随电位变化的极限还原电流,在该电位范围内进行电沉积获得了化学计量组成稳定可控且相对致密平整的CuInSe_2薄膜。

CONTROLLABLE ELECTRODEPOSITION OF CuInSe_2 THIN FILMS FOR SOLAR CELLS

CuInSe_2 thin films were prepared by potentiostatic electrodeposition. Electrochemical behaviors of Cu~(2+) , In~(3+)and H_2SeO_3 in idividual electrodeposition and co-electrodeposition were studied by cyclic voltammetry. The influence of deposition potential on film stoichiometry, morphology and structure were also investigated. The results showed that cit-rate ions presents the complexing effect on Cu~(2+) and H_2SeO_3 but no effect on In~(3+). When co-ectrodeposition, Cu reduces first, then the Se reduction which leads to Cu_x Se formation. Cu_x Se finally induces In~(3+) reduction and CuInSe_2 (CIS) for-mation. A limiting current was abserved at potentials between - 0.58 ～ - 0.90V vs the saturated calomel electrode (SCE) at which smooth and dense CIS thin films with controllable stoichiometry have been obtained.