Synergic Reaction Kinetics over Adjacent Ruthenium Sites for Superb Hydrogen Generation in Alkaline Media

Abstract

Ruthenium (Ru)‐based electrocatalysts as platinum (Pt) alternatives in catalyzing hydrogen evolution reaction (HER) are promising. However, achieving efficient reaction processes on Ru catalysts is still a challenge, especially in alkaline media. Here, the well‐dispersed Ru nanoparticles with adjacent Ru single atoms on carbon substrate (Ru1,n‐NC) is demonstrated to be a superb electrocatalyst for alkaline HER. The obtained Ru1,n‐NC exhibits ultralow overpotential (14.8 mV) and high turnover frequency (1.25 H2 s‐1 at −0.025 V vs reversible hydrogen electrode), much better than the commercial 40 wt.% Pt/C. The analyses reveal that Ru nanoparticles and single sites can promote each other to deliver electrons to the carbon substrate. Eventually, the electronic regulations bring accelerated water dissociation and reduced energy barriers of hydroxide/hydrogen desorption on adjacent Ru sites, then an optimized reaction kinetics for Ru1,n‐NC is obtained to achieve superb hydrogen generation in alkaline media. This work provides a new insight into the catalyst design in simultaneous optimizations of the elementary steps to obtain ideal HER performance in alkaline media.

Convenient Synthesis of a Ru Catalyst Containing Single Atoms and Nanoparticles on Nitrogen-Doped Carbon with Superior Hydrogen Evolution Reaction Activity in a Wide pH Range

“…Zhang et al synthesized an electrocatalyst containing both Ru single atoms and nanoparticles anchored on defective carbon via a Ru–alginate metal-organic supramolecules conversion method . Song et al synthesized well-dispersed Ru nanoparticles with adjacent Ru single atoms on a carbon substrate (Ru 1, n -NC) through the pyrolysis of Ru-anchoring polypyrrole at high temperature . The atomic dispersed Ru in the substrate can significantly reduce the adsorption capacity of active hydrogen, , while Ru nanoparticles can reduce the dissociation energy of water.…”

The Progress and Outlook of Metal Single-Atom-Site Catalysis

“…CC BY 4.0. Panels (c–e) are adapted with permission from (c) ref and (d, e) ref . Copyright 2021 and 2022, respectively, Wiley-VCH.…”

“…Song et al reported an NSASC with Ru NPs and Ru single atoms on a carbon substrate (Ru 1,n -NC) that exhibited excellent activity in alkaline HER. 113 The electron interaction between Ru NPs and Ru 1 sites endowed Ru-NSASCs with stronger H 2 O dissociation ability and weaker OH adsorption energy than Ru 1 sites and Ru NPs, which was beneficial to the desorption of OH to release active sites. The energy barriers of water activation were 0.05 and 0.30 eV on the Ru 1 site and Ru NPs in Ru-NSASCs, respectively, which are much lower than those on single Ru 1 sites and Ru NPs (0.40 and 0.95 eV, respectively) (Figure 11d,e).…”

“…Such electronic synergy endowed Ni SA/NP with a high CO current density of 346 mA cm –2 at −0.5 V vs RHE in an alkaline flow cell. Song et al reported an NSASC with Ru NPs and Ru single atoms on a carbon substrate (Ru 1, n -NC) that exhibited excellent activity in alkaline HER . The electron interaction between Ru NPs and Ru 1 sites endowed Ru-NSASCs with stronger H 2 O dissociation ability and weaker OH adsorption energy than Ru 1 sites and Ru NPs, which was beneficial to the desorption of OH to release active sites.…”

Embedded Ruthenium Nanoparticles within Exfoliated Nanosheets of Ti3C2Tx for Hydrogen Evolution

“…The higher initial potential for CO oxidation represented a weaker hydroxide adsorption on Ru@M-OH and thus implied an enhanced water activation capability for improved HER in alkaline media. 30 In addition, the electrochemical surface area was evaluated by double-layercapacitance (DLC) measurement. Figures 3d and S6 illustrate the enlarged area obtained on Ru@M-OH, suggesting that more active sites were activated and generated by the OH −modified Ru intercalation approach.…”