Polycrystalline Cu(In,Ga)S₂ (CIGS) nanowire arrays (NWAs) are synthesized for the first time via a solvothermal method using Cu₂S NWAs as self-sacrificial templates. The average diameter and length of the as-synthesized CIGS nanowires are 350 nm and 5 μm, respectively. Based on the experimental results, a novel cation-exchange growth mechanism is proposed. The In³⁺ and Ga³⁺ ions diffuse inward while the Cu⁺ ions outward during the solvothermal reaction, resulting in the formation of CIGS with keeping the original nanowire morphology. We have also investigated the photoelectrochemical performance of CIGS NWAs compared with the pristine Cu₂S templates. The photocurrent density and optimal incident photon to current efficiency of CIGS NWAs are 0.39 mA cm⁻² and 6% at 450 nm, respectively, which are much higher than those of the Cu₂S templates. The reported method will lay a foundation for the synthesis of other multi-compound (ternary and above) metal chalcogenides for PEC applications.

以Cu ₂ S NWAs为自牺牲模板，通过溶剂热法首次合成了多晶Cu（In，Ga）S ₂（CIGS）纳米线阵列（NWAs）。合成后的CIGS纳米线的平均直径和长度分别为350 nm和5μm。基于实验结果，提出了一种新型的阳离子交换生长机理。在溶剂热反应中，In ³⁺和Ga ³⁺离子向内扩散，而Cu ⁺离子向外扩散，从而形成了CIGS，并保持了原始的纳米线形态。我们还研究了CIGS NWA与原始Cu ₂相比的光电化学性能S个模板。CIGS NWA的光电流密度和最佳入射光子对电流效率在450 nm处分别为0.39 mA cm ^-2和6％，远高于Cu ₂ S模板。报道的方法将为合成其他用于PEC应用的多化合物（三元及以上）金属硫属化合物奠定基础。