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Abstract The development of efficient and economical electrocatalysts for oxygen evolution reaction (OER) is of paramount importance for the sustainable production of renewable fuels and energy storage systems; however, the sluggish OER kinetics involving multistep four proton‐coupled electron transfer hampers progress in these systems. Fortunately, surface reconstruction offers promising potential to improve OER catalyst design. Anion modulation plays a crucial role in controlling the extent of surface reconstruction and positively persuading the reconstructed species' performances. This review starts by providing a general explanation of how various types of anions can trigger dynamic surface reconstruction and create different combinations with pre‐catalysts. Next, the influences of anion modulation on manipulating the surface dynamic reconstruction process are discussed based on the in situ advanced characterization techniques. Furthermore, various effects of survived anionic groups in reconstructed species on water oxidation activity are further discussed. Finally, the challenges and prospects for the future development directions of anion modulation for redirecting dynamic surface reconstruction to construct highly efficient and practical catalysts for water oxidation are proposed.

Abstract The oxygen evolution reaction (OER) activity of single‐atom catalysts (SACs) is closely related to the coordination environment of the active site. Oxygen‐coordinated atomic metal species bring about unique features beyond nitrogen‐coordinated atomic metal species due to the fact that the M–O bond is weaker than the M–N bond. Herein, a series of metal–oxygen–carbon structured low‐nucleus clusters (LNCs) are successfully anchored on the surface of multiwalled carbon nanotubes (M‐MWCNTs, M = Ni, Co, or Fe) through a foolproof low‐temperature gas transfer (300°C) method without any further treatment. The morphology and coordination configuration of the LNCs at the atomic level were confirmed by comprehensive characterizations. The synthetic Ni‐MWCNTs electrocatalyst features excellent OER activity and stability under alkaline conditions, transcending the performances of Co‐MWCNTs, Fe‐MWCNTs and RuO2. Density functional theory calculations reveal that the moderate oxidation of low‐nucleus Ni clusters changes the unoccupied orbital of Ni atoms, thereby lowering the energy barrier of the OER rate‐limiting step and making the OER process more energy‐efficient. This study demonstrates a novel versatile platform for large‐scale manufacturing of oxygen‐coordinated LNC catalysts.

Abstract Efficient electrocatalysts for the oxygen evolution reaction (OER) are highly desirable because of the intrinsically sluggish kinetics of OER. Herein, core–shell structured nanospheres of NiFexSn@NiFe (oxy)hydroxide (denoted as NiFexSn‐A) are prepared as active OER catalysts by a facile electrochemical strategy, which includes electrodeposition of NiFexSn alloy nanospheres on carbon cloth (CC) and following anodization. The alloy core of NiFexSn could promote charge transfer, and the amorphous shell of NiFe (oxy)hydroxide is defect‐rich and nanoporous due to the selective electrochemical etching of Sn in alkaline medium. The optimized catalyst of NiFe0.5Sn‐A displays a remarkable OER performance with a low overpotential of 260 mV to reach the current density of 10 mA cm−2, a small Tafel slope of 50 mV dec−1, a high turnover frequency of 0.194 s−1 at an overpotential of 300 mV, and a robust durability. Further characterizations indicate that the superior OER performance of the core–shell structured NiFe0.5Sn‐A nanospheres might originate from abundant active sites and small charge transfer resistance. This work brings a new perspective to the design and synthesis of core–shell structured nanospheres for electrocatalysis through a facile electrochemical strategy.