Solution Plasma‐Assisted Multivariate Metal Nanoalloys Encapsulated with Carbon Dots for Efficient Oxygen Evolution Reaction

Abstract To accelerate the reaction kinetics of electrocatalytic oxygen evolution reaction (OER), a multicomponent CDs@(PdFeNiCo)Nb x nanohybrid comprising multiple metal nanoalloys and carbon quantum dots (CDs) was in situ generated by treating the mixture of Nb 2 C quantum dots (Nb 2 C QDs) and a variety of metal ions (M 2+ =Pd 2+ , Fe 2+ , Co 2+ , Ni 2+ ) through the solution plasma (SP) modification technique. The CDs@(PdFeNiCo)Nbx catalyst was further explored as an electrocatalyst for OER in alkaline solution. Under nitrogen plasma irradiation with high input power (200 W), diverse bimetallic nanoalloy particles, including NbPd 3 , FeNb, NbNi 3 , and CoNbO 4 nanoalloys, were generated, accompanied with the decomposition of Nb 2 C QDs into CDs. In view of the synergic effect between multivariate metal active sites and highly conjugated CD network, the developed CDs@(PdFeNiCo)Nb x electrocatalyst showed a small overpotential of 240 mV for achieving the current density of 10 mA cm −2 , together with a very low Tafel slope of 62 mV dec −1 , which substantially outperformed those of the state‐of‐the‐art metal electrocatalysts and was competitive with most metal oxides. The CDs@(PdFeNiCo)Nb x electrocatalyst also showed a negligible overpotential change during 30 h chronopotentiometry measurement. The present work can provide a feasible alternative strategy for the development of an excellent OER electrocatalyst using the SP modification method.