Integrating RuCo alloy in N-doped carbon nanofiber for efficient hydrogen evolution in alkaline media.

Ruthenium (Ru) is considered as a promising element for constructing alkaline hydrogen evolution (HER) catalysts due to its rapid water dissociation kinetics and low-cost advantages than Pt. Alloying can optimize the electrochemical performance of metals and reduce the usage of the noble metal. Herin, RuCo alloy nanoparticles were grown in-situ on N-doped carbon nanofibers (RuCo/NCNF) by electrospinning and graphitization. Under thermodynamic driving force, the Ru and Co elements formed RuCo alloys. It is worth noting that the Ru not only improved the catalytic performance, but also reduced the nanoparticle size and exposing more active sites. Moreover, N-doped carbon nanofiber was not only used to load RuCo alloy nanoparticle, but also as a good substrate for the HER reaction. Therefore, the RuCo/NCNF had fabulous catalytic activity in alkaline media. Furthermore, the in-situ growth also endowed the RuCo/NCNF with excellent stability, HER performance was not significantly reduced even after 40 h stability test. And when the Ru:Co = 1:8, RuCo/NCNF had the excellent HER catalytic performance. Only 41 mV was required to drive a current density of 10 mA cm−2, with Tafel Slope as low as 64.8 mV dec−1. • RuCo alloy nanocrystals were growing in-situ on N-doped carbon nanofibers. • The strong synergetic behavior between Ru and Co via alloying improved and optimized the electrochemical performance of catalysts. • RuCo alloy nanocrystals anchored on N-doping carbon nanofibers exhibit exceedingly low overpotentials and small Tafel slopes in alkalinemV. • It presents superb conductivity and durable stability with the existence and protection of carbon. [ABSTRACT FROM AUTHOR]