Origin of the superior oxygen reduction activity of zirconium nitride in alkaline media

Abstract

The anion exchange membrane fuel cell (AEMFC), which can operate in alkaline media, paves a promising avenue for the broad application of earth-abundant element based catalysts. Recent pioneering studies found...

Reversible Hydrogen Electrode (RHE) Scale Dependent Surface Pourbaix Diagram at Different pH

“…Additionally, solvation corrections were applied to the HO* species to account for the substantial stabilization effects arising from strong hydrogen bonding. The values for these solvation corrections were referenced from previous reports. , The water dissociation equilibrium over the course of electrocatalysis can be represented by H n O m * + false( 2 m − n ) * false( H + + e − false) ⇄ * + m H 2 normalO in which, m and n represent the quantities of O and H atoms, respectively, that are adsorbed onto a pristine surface. The free energies of each surface state represented in the surface Pourbaix diagram ( G SP ) can be derived by the following equation: G SP = G bare + m G H 2 normalO − G tot − false( 2 m − n false) ( 1 2 G H 2 − U SHE − k B T ln false( 10 false) × pH ) in which, G bare , G H 2 O , G tot , and G H 2 represent the total energies of a pristine surface, a water molecule, the surface with adsorbates, and a hydrogen molecule.…”

“…The values for these solvation corrections were referenced from previous reports. 58,59 The water dissociation equilibrium over the course of electrocatalysis can be represented by 26…”

Origin of electrocatalytic nitrogen reduction activity over transition metal disulfides: critical role of in situ generation of S vacancy

“…33 Very recently, we found that only when we consider a more realistic surface coverage of ZrN can we fully understand its superior electrocatalytic oxygen reduction performance with good agreement with experiments. 34 Therefore, for ENRR analysis, it is reasonable to hypothesize that in the presence of a low potential, anion vacancies may be directly formed on some TMXs ( e.g ., TMS 2 ) because protons and electrons can easily combine with the surface and lead to the leaching out of the anions of the material. This may lead to the formation of vacancies, which would significantly change the type of active sites and electronic structures of an ENRR catalyst.…”

Identifying Stable Electrocatalysts Initialized by Data Mining: Sb2WO6 for Oxygen Reduction

“…Moreover, considering the electrochemical surface states of MOs under operating conditions is essential because a surface can be pre-covered by the adsorbates (e.g., HO*, O*, and H*) generated by the electrochemistry-driven water activation, [31][32][33] leading to deviations from their pristine surface, ultimately impacting the stability and activity of MOs. [34,35] The phenomenon of surface coverage has been observed in dual-atom catalysts [32] and various X-ides (e.g., oxides, nitrides, carbides, and hydroxides) catalysts. [31,34] Additionally, the pH of the surrounding environment significantly influences the catalyst's performance.…”

“…[34,35] The phenomenon of surface coverage has been observed in dual-atom catalysts [32] and various X-ides (e.g., oxides, nitrides, carbides, and hydroxides) catalysts. [31,34] Additionally, the pH of the surrounding environment significantly influences the catalyst's performance. Therefore, a comprehensive analysis considering both the electrochemical surface states and pH effects is indispensable to unravel the intricate origin of MOs' catalytic activity.…”