Nanocomposites based on Cu2O coated silver nanowire networks for high-performance oxygen evolution reaction†

The development of highly active, low-cost, and robust electrocatalysts for the oxygen evolution reaction (OER) is a crucial endeavor for the clean and economically viable production of hydrogen via electrochemical water splitting. Herein, cuprous oxide (Cu₂O) thin films are deposited on silver nanowire (AgNW) networks by atmospheric-pressure spatial atomic layer deposition (AP-SALD). AgNW@Cu₂O nanocomposites supported on conductive copper electrodes exhibited superior OER activity as compared to bare copper substrate and bare AgNWs. Moreover, a relationship between Cu₂O thickness and OER activity was established. Notably, the most effective catalyst (AgNW@50nm-thick Cu₂O) demonstrated very high OER activity with a low overpotential of 409 mV to deliver a current density of 10 mA cm⁻² (η₁₀), a Tafel slope of 47 mV dec⁻¹, a turnover frequency (TOF) of 4.2 s⁻¹ at 350 mV, and good durability in alkaline media (1 M KOH). This highlights the potential of AgNWs as a powerful platform for the formation of highly efficient copper oxide catalysts towards OER. This work provides a foundation for the development of nanostructured Cu-based electrocatalysts for future clean energy conversion and storage systems.