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The state-of-the-art transition-based electrocatalysts in alkaline media generally suffer from unavoidable surface reconstruction during oxygen evolution reaction measurements, leading to the collapse and loss of the crystalline matrix. Low potential discharge offers a gentle way for surface reconstruction and thus realizes the manipulation of the real active site. Nevertheless, the absence of a fundamental understanding focus on this discharge region renders the functional phase, either the crystalline or amorphous matrix, for the controllable reconstruction still undecidable. Herein, we report a scenario to employ different crystalline matrices as electrocatalysts for discharge region reconstruction. The representative low crystalline Ni 2 P (LC-Ni 2 P) possesses a relatively weak surface structure compared with highly crystalline or amorphous Ni 2 P (HC-Ni 2 P or A-Ni 2 P), which contributes abundant oxygen vacancies after the discharge process. The fast discharge behavior of LC-Ni 2 P leads to the uniform distribution of these vacancies and thus endows the inner interface with reactant activating functionality. A high increase in current density of 36.7% is achieved at 2.32 V (vs RHE) for the LC-Ni 2 P electrode. The understanding of the discharge behavior in this study, on different crystalline matrices, presents insights into the establishment of controllable surface reconstruction for an effective oxygen evolution reaction.

Regulating the composition of the electrolyte by cation additions remarkably promotes the oxygen evolution reaction kinetics of electrocatalysts. However, the correlation between the catalytic behavior and cation additions, a necessary requirement for the fundamental understanding of the mechanism, is particularly elusive. Here, we identify how Co2+ and Zn2+ cation additions affect the electrocatalyst structural stability and the oxygen evolution reaction (OER) kinetics. We show that tuning the composition of the electrolyte by controlling the cation additions can alter the transport ability of the electrolyte. This cation transport effect, acting on a combination of electron and active species, activates the inner metal site and facilitates the reaction paths. These findings are meaningful in that the experimental results are theoretically verified through finite element method calculations. The Co2+ cation addition endows the OER of NiFeO x H y at 2.2 V (vs reversible hydrogen electrode (RHE)) with a current density increase of 32.7%. The present study highlights the significance of the cation transport effect and proposes an advanced strategy for electrode engineering.