A solution-based oxidation–reduction approach for spontaneous construction of nanowire architectures on copper metals

Copper (Cu) is a critically important functional material with widespread applications in catalysis, battery technology, and sensing. The oxidation–reduction approach serves as an efficient means to modify Cu metals, enabling the creation of nanowire architectures that expand their specific surface area and facilitate the engineering of catalytic active sites. However, the crucial issue is that the reduction process typically requires high-temperature treatment in an H₂ atmosphere, which is laborious and demanding. Here using the dimethylamine methyl borane (C₂H₁₀BN) as an efficient reduction reagent, we report a facile solution-based oxidation–reduction approach at room temperature for the direct formation of the nanowire architectures on commercial Cu foams (CF), resulting in a unique three-dimensional (3D) hierarchically skeleton architecture. Moreover, as a typical application, cobalt hydroxide (Co(OH)₂) is electrodeposited on the CF with nanowires (CFNW) to form a CFNW/Co(OH)₂ electrode for oxygen evolution reaction (OER). The obtained results indicate the nanowire structure significantly increases the contact area between Co(OH)₂ and CFNW substrate, resulting in an outstanding OER performance with an overpotential of 175 mV at 10 mA cm⁻² in 1 M KOH. Importantly, this study presents a straightforward modification approach applicable to Cu metals, enabling large-scale production of advanced 3D skeleton Cu materials with diverse applications.