Bimetallic cobalt-rich Co_0.63Ru_0.37 nanoalloys encapsulated in carbon nanofibers expediting oxygen evolution reaction under acidic solution

Electrochemical water splitting holds great promise as a sustainable method for oxygen production through energy conversion. However, the scarcity and limited durability of noble metals like Pt, Ru, and Ir, which exhibit excellent electrochemical activity, impede their practical and large-scale application in electrochemical devices. In order to tackle this issue, we prepared bimetallic single-phase Co_0.63Ru_0.37 nanoalloys encapsulated in carbon nanofibers (Co_0.63Ru_0.37/CNFs) for highly efficient water oxidation electrocatalysis. This was achieved through a single-step electrospinning process followed by thermal annealing under an inert atmosphere. Co_0.63Ru_0.37/CNFs demonstrated exceptional electrocatalytic performance for the oxygen evolution reaction (OER), with an overpotential of only 206 mV at 10 mA cm⁻² and a Tafel slope of 46.4 mV dec⁻¹, indicating a high level of activity and long-term stability in acidic solutions. Additionally, Co_0.63Ru_0.37/CNFs exhibited superior OER performance compared to a commercial benchmark catalyst (cIr, 20 wt% metal loading on Vulcan XC-72) in acidic solutions, highlighting their potential as an efficient OER electrocatalyst for acidic water electrolysis. Furthermore, Co_0.63Ru_0.37/CNFs offer cost-effectiveness due to their primarily carbon composition, with noble Ru accounting for only half of the total metal content.