Hierarchical PtCuMnP Nanoalloy for Efficient Hydrogen Evolution and Methanol Oxidation

Abstract

AbstractThe higher amount of Pt usage and its poisoning in methanol oxidation reaction in acidic media is a major setback for methanol fuel cells. Herein, a promising dual application high‐performance electrocatalyst has been developed for hydrogen evolution and methanol oxidation. A low Pt‐content nanoalloy co‐doped with Cu, Mn, and P is synthesized using a modified solvothermal process. Initially, ultrasmall ≈2.9 nm PtCuMnP nanoalloy is prepared on N‐doped graphene‐oxide support and subsequently, it is characterized using several analytical techniques and examined through electrochemical tests. Electrochemical results show that PtCuMnP/N‐rGO has a low overpotential of 6.5 mV at 10 mA cm−2 in 0.3 m H2SO4 and high mass activity for the hydrogen evolution reaction. For the methanol oxidation reaction, the PtCuMnP/N‐rGO electrocatalyst exhibits robust performance. The mass activity of PtCuMnP/N‐rGO is 6.790 mA mg−1Pt, which is 7.43 times higher than that of commercial Pt/C (20% Pt). Moreover, in the chronoamperometry test, PtCuMnP/N‐rGO shows exceptionally good stability and retains 72% of the initial current density even after 20,000 cycles. Furthermore, the PtCuMnP/N‐rGO electrocatalyst exhibits outstanding performance for hydrogen evolution and methanol oxidation along with excellent anti‐poisoning ability. Hence, the developed bifunctional electrocatalyst can be used efficiently for hydrogen evolution and methanol oxidation.