RuO2 as promoter in Pt-RuO2-nanostructures/carbon composite, a pH-universal catalyst for hydrogen evolution/oxidation reactions

The development of new catalysts for Hydrogen evolution reaction/Hydrogen oxidation reaction (HER/HOR) is of crucial importance for the commercialization of Proton-exchange membrane/Anion-exchange membrane-based renewable technologies. The sluggish HER/HOR kinetic (in base) and poor HER/HOR stability (in acid) of commercial Pt/C are the main obstacles. Interface engineering in multi-component nanostructures is a method for enhanced electrochemical performances. We report interfaces-engineered RuO2-Pt/C as a pH-independent catalyst for Hydrogen oxidation reaction/Hydrogen evolution reaction applications. The Hydrogen oxidation reaction/Hydrogen evolution reaction activity of RuO2-Pt/C is one order magnitude higher than commercial Pt/C in base and 2.5-fold higher in acid. It shows excellent stability in acid and base. It exhibits excellent pH tolerant HOR behavior. The i(o,m) of RuO2-Pt/C in the base is similar to 1833 A.g(Rupt)(-1) which is 8-fold higher than commercial Pt/C. The RuO2 in RuO2-Pt/C makes it more active toward HER/HOR in base. Although it has similar activity in acid, its basic activity is 29-fold higher than Ru-Pt-NPs/ C. Hydrogen binding energy and OH binding energy are two equivalent descriptors for HOR/HER in base. HOR/HER activity of this catalyst in different 0.1 M electrolyte decreases in the sequence of Li+ > Na+ > K+ but improved HER and decreased HOR is observed with increasing Li(+ )ions. The [(H2O)(x)-( AM(+)-(OH)(ad)] in double-layer influences HOR/HER performance of RuO2-Pt/C. This catalyst has great potential for application in PEM/AEM-based devices.

Automated summary

Interfaces-engineered RuO2-Pt/C, as a pH-independent catalyst, shows superior activity and stability for Hydrogen oxidation reaction/Hydrogen evolution reaction applications compared to commercial Pt/C.