Aprotic lithium-oxygen batteries (LOBs) with high theoretical energy density have received considerable attention over the past years. However, the oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) at cathodes suffer from slow kinetics for large overvoltages in LOBs. Significant advances on catalysts have been achieved to accelerate cathode kinetics, but understanding on the formation/decomposition processes of Li₂O₂ is limited. Herein, this review highlights the fundamental understanding of the correlation between catalysts and formation/decomposition of Li₂O₂. Various types of cathode catalysts are discussed to reveal the mechanism of formation/decomposition of Li₂O₂, aiming to present the prerequisites for the design of highly efficient cathode catalysts. Future prospects of comprehensive consideration on introduction of light or magnetism, protection of Li metal anode, and electrolyte engineering are presented for the further development of LOBs.

Electrolytic hydrogen production is heavily restricted by high-energy consumption majorly due to the relatively high potential of anodic oxygen evolution reaction (OER). Development of OER-alternative reaction at the anode has been recently proposed as a promising pathway to address the associated issues. In this work, we report a hybrid acid/alkali dual-electrolyte electrolyzer by coupling acidic hydrogen evolution reaction (HER) using commercial Pt/C cathode with alkaline electrocatalytic glycerol oxidation (GOR) which is implemented by developing a nickel foam (NF) supporting Co₃O₄ nanosheets anode that shows low overpotential and high selectivity toward GOR for formate production. The hybrid acid/alkali electrolyzer only requires an applied voltage of 0.55 V to achieve the electrolytic current density of 10 mA·cm^-2 for glycerol conversion into formate at the anode and H₂ production at the cathode with the Faraday efficiency of about 100%. The present work may open a new avenue to maximize the electron utilization efficiency and implement the energy-saving green route for H₂ generation.

Solid oxide electrolysis cell (SOEC) as an electrochemical energy conversion device has attracted increasing attention due to its large current density, high Faradaic efficiency and energy efficiency. Oxygen evolution reaction at the anode, a four-electron transfer process, is an important half-reaction for SOEC, which contributes to the main polarization resistance and consumes most electric energy during the electrolysis process. Hence, designing anode materials with high activity and stability is crucial for the performance improvement and practical application of SOEC. Recently, some advances have been made in the development of high-performance anode. In the current review, the mechanisms for CO₂ and/or H₂O electrolysis are highlighted. The physicochemical and electrochemical properties of different types of anodes are summarized. Various efficient strategies for anode optimization are introduced. Furthermore, the outlook for the future research of SOEC is included. This review might be helpful for the development of anode materials and the practical application of SOEC.

Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell, which has already attracted growing popularities. However, current methanol oxidation electrocatalysts fall far short of expectations and suffer from excessive use of noble metal, mediocre activity, and rapid decay. Here we report the Pt anchored on NiFe-LDHs surface hybrid for stable methanol oxidation in alkaline media. Based on the high intrinsic methanol oxidation activity of Pt nanoparticles, the substrates NiFe-LDHs further enhanced anti-poisoning ability and maintained unaffected stability after 200,000 s cycle test compared to commercial Pt/C catalyst. The use of NiFe-LDHs is believed to play the decisive role to evenly disperse Pt nanoparticles on their surface using single atomic dispersed Fe as anchoring sites, making full use of abundant OH groups and subsequent facilitating the oxidative removal of carbonaceous poison on neighboring Pt sites. This work highlights the specialty of NiFe-LDHs in improving the overall efficiency of methanol oxidation reaction.