Developing anodic oxygen evolution reaction (OER) electrocatalysts with high catalytic activities is of great importance for effective water splitting. Compared with the water‐oxidation electrocatalysts that are commonly utilized in alkaline conditions, the ones operating efficiently under neutral or near neutral conditions are more environmentally friendly with less corrosion issues. This review starts with a brief introduction of OER, the importance of OER in mild‐pH media, as well as the fundamentals and performance parameters of OER electrocatalysts. Then, recent progress of the rational design of electrocatalysts for OER in mild‐pH conditions is discussed. The chemical structures or components, synthetic approaches, and catalytic performances of the OER catalysts will be reviewed. Some interesting insights into the catalytic mechanism are also included and discussed. It concludes with a brief outlook on the possible remaining challenges and future trends of neutral or near‐neutral OER electrocatalysts. It hopefully provides the readers with a distinct perspective of the history, present, and future of OER electrocatalysts at mild conditions.

The Haber−Bosch process for industrial NH 3 production suffers from harsh reaction conditions and serious CO 2 emission. Electrochemical N 2 reduction offers a carbon-neutral alternative for more energy-saving NH 3 synthesis but requires active electrocatalysts for the N 2 reduction reaction (NRR). In this Letter, boron nanosheet (BNS) is proposed as an elemental two-dimensional (2D) material to effectively catalyze the NRR toward NH 3 synthesis with excellent selectivity. When tested in 0.1 M Na 2 SO 4 , such BNS catalyst attains a high Faradaic efficiency of 4.04% and a large NH 3 yield of 13.22 μg h −1 mg cat −1 at −0.80 V vs reversible hydrogen electrode, with strong electrochemical durability. Density functional theory calculations suggest that the B atoms of both oxidized and H-deactivated BNS can catalyze the NRR more effectively than clean BNS, and the rate-determining step is the desorption process of the second NH 3 gas.

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Electrochemical CO2 reduction under ambient conditions is a promising pathway for conversion of CO2 into value‐added products. In recent years, great achievements have been obtained in the understanding the mechanism and development of efficient and selective catalysts for electrochemical CO2 reduction. However, the electrochemical CO2 reduction is still far from practical applications. Based on the gap between current research and practical applications, the state‐of‐the‐art of the theoretical and experiment investigations on different electrocatalysts for the electrocatalysis of CO2 to CH4 is systematically and constructively reviewed. First of all, strategies for enhancing the catalytic activity and selectivity of electrochemical reduction of CO2 to CH4 are also examined in this review. The modulated strategies mainly involve the following aspects: i) tuning the applied potentials, ii) morphology engineering, iii) crystallographic facets engineering, iv) defect engineering, v) alloying. Furthermore, the influence of the electrolyte on the activity and selectivity for electrocatalysis of CO2 to CH4 is also reviewed. This review will build a systematic understanding in the electrochemical CO2 reduction to CH4 and may help to provide new insight for designing and optimizing the catalysts and/or electrolyte.

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