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Recently, Ni‐based chalcogenides havedemonstrated remarkable activity and selectivity for alcohol electrooxidation, but the mechanisms remain debated. This study synthesizes Ni‐based electrodeswith different chalcogen anion coordination on nickel nanorod arrays (NiOx/Ni,NiSx/Ni, and NiSex/Ni NRAs). NiSex/Ni NRAsshowcases superior performance (Faradaic efficiency 92.9%) in glycerolelectrooxidation reaction (GOR). In situ spectroscopy reveals that NiSecoordination inhibits deep oxidative reconstruction of the Ni‐based interface, preventingNiOOH phase formation during GOR, enhancing activity and stability of NiSex/NiNRAs. Conversely, NiS and NiO coordination lead to deep reconstruction with NiOOHphase formation, limiting GOR performance. Differently, during competingreaction of GOR, the oxygen evolution reaction (OER) leads to deepreconstruction of NiSex interface due to the instability of Ni‐Sebonds, inducing performance degradation and dissolution of Se components. Furthermechanism investigation elucidates that the rate‐determining step (RDS) ofGOR at the NiSex interface involves oxidation of *C2H3O3 intermediatesthrough H2O adsorption, favoring stable formate production.Contrarily, the RDS at the NiSx, NiOx, and NiOOHinterfaces predominantly focus on the decarboxylation of multi‐carbon intermediates, raisingenergy barriers and over‐oxidizing formate to CO2. These results providenew insights for designing Ni‐based non‐oxide catalysts forefficient and stable electrocatalytic oxidation. [ABSTRACT FROM AUTHOR]

Large‐scale production of hydrogen from water‐alkali electrolyzers is impeded by the sluggish kinetics of hydrogen evolution reaction (HER) electrocatalysts. The hybridization of an acid‐active HER catalyst with a cocatalyst at the nanoscale helps boost HER kinetics in alkaline media. Here, it is demonstrated that 1T–MoS2 nanosheet edges (instead of basal planes) decorated by metal hydroxides form highly active edge1T‐MoS2/edgeNi(OH)2 heterostructures, which significantly enhance HER performance in alkaline media. Featured with rich edge1T‐MoS2/edgeNi(OH)2 sites, the fabricated 1T–MoS2 QS/Ni(OH)2 hybrid (quantum sized 1T–MoS2 sheets decorated with Ni(OH)2 via interface engineering) only requires overpotentials of 57 and 112 mV to drive HER current densities of 10 and 100 mA cm−2, respectively, and has a low Tafel slope of 30 mV dec−1 in 1 m KOH. So far, this is the best performance for MoS2‐based electrocatalysts and the 1T–MoS2 QS/Ni(OH)2 hybrid is among the best‐performing non‐Pt alkaline HER electrocatalysts known. The HER process is durable for 100 h at current densities up to 500 mA cm−2. This work not only provides an active, cost‐effective, and robust alkaline HER electrocatalyst, but also demonstrates a design strategy for preparing high‐performance catalysts based on edge‐rich 2D quantum sheets for other catalytic reactions. [ABSTRACT FROM AUTHOR]