硫代硫酸钠诱导CoS多孔薄膜在铜表面的浸镀沉积

Sodium thiosulfate assisted immersion deposition of CoS porous film on copper

浸镀沉积是指利用化学置换反应将金属薄膜沉积到另外一种具有更低电位金属表面的方法,具有高效性和简便性等特点。钴具有较铜更低的标准电位,为了使钴能在铜表面直接沉积,采用了一种改进的浸镀沉积方法,实现了在铜表面直接浸镀沉积钴基薄膜。由于硫代硫酸钠具有较强的铜配位能力而较弱的钴配位能力,开路电位测试表明硫代硫酸钠能够显著降低铜的电位,使之低于钴的电位,使钴在铜表面的浸镀沉积成为可能。此外,由于硫代硫酸钠易分解产生硫,因此在钴浸镀沉积的同时,硫可以掺入钴薄膜,从而获得CoS薄膜。经SEM、EDS、XPS和XRD表征验证,CoS薄膜主要由CoS相组成,具有多孔结构的形貌特征。所制备的CoS多孔薄膜在1.0mol/L KOH溶液中呈现出较好的水分解析氧电催化性能。

Immersion deposition is an effective and versatile approach to synthesize metallic films on less noble metal substrate via galvanic replacement reaction.However,in this work,a modified immersion deposition route is developed to achieve facile synthesis of cobalt-based films on copper,which has a higher standard electrode potential than cobalt.The open circuit potential tests demonstrate that sodium thiosulfate plays an important role in decreasing the potential of copper to be lower than cobalt for its strong complexation ability to copper but weak complexation ability to cobalt,which thus makes the spontaneous replacement deposition of cobalt on copper a reality.Meanwhile,because sodium thiosulfate is prone to decompose into sulfur,sulfur can be codeposited with cobalt and the Co S nanostructured film is finally obtained.As verified by the SEM,EDS,XPS and XRD characterization,the Co S nanostructured film shows porous and crude morphology and is mainly composed of Co S phase.The as-prepared Co S nanostructured film possesses good electrocatalytic performance for oxygen evolution reaction in 1.0 M KOH solution.