Recent Development and Future Perspectives of Amorphous Transition Metal‐Based Electrocatalysts for Oxygen Evolution Reaction

Abstract

Oxygen evolution reaction (OER), as a relevant half reaction for water splitting to address the energy crisis, has captured a great deal of attention. However, this technology has always been impeded by the lack of a highly efficient and stable electrocatalyst. Amorphous materials, which possess long‐range disorder and only short‐range order over a few atoms, are often superior to their crystalline counterparts in electrocatalysis owing to their more active sites, broader chemical composition range, and more structural flexibility. This review first introduces some assessment criteria for the OER and then presents theoretical modeling of the OER mechanisms and the state‐of‐the‐art amorphous transition metal‐based OER electrocatalysts, involving oxides, hydroxides, sulfides, phosphides, borides, and their composites, as well as their practical applications in the OER. Finally, recent development, existing challenges, and future perspectives for amorphous transition metal‐based OER electrocatalysts are discussed. This paper offers valuable guidance in designing highly efficient and stable amorphous OER electrocatalysts for future energy applications.

Anodization of a NiFe Foam: An Efficient and Stable Electrode for Oxygen-Evolution Reaction

“…This shows that after the anodization under a high potential of 60 V, the metallic structure of the surface immediately converts to metal-oxide-based compounds with low crystallinity. Indeed, such amorphous metal oxides with no long-range disorder and only short-range order over a few atoms are efficient catalysts for the OER, given their large surface, high active sites, broader chemical composition range, more dangling bonds and unsaturated atoms, more defects, structural disorder, and more flexibility during the OER …”

“…Indeed, such amorphous metal oxides with no long-range disorder and only short-range order over a few atoms are efficient catalysts for the OER, given their large surface, high active sites, broader chemical composition range, more dangling bonds and unsaturated atoms, more defects, structural disorder, and more flexibility during the OER. 54 Based on the Scherrer equation (eq 2), 55…”

Recent advances in amorphous electrocatalysts for oxygen evolution reaction

“…The water electrolysis consists of two coupled half-reactions, which are the hydrogen evolution reaction (HER) in the cathode and the oxygen evolution reaction (OER) in the anode. Between the reactions, OER requires a higher overpotential than HER due to the sluggish kinetics of the complicated reaction mechanism, and significantly lowers the efficiency of the overall water electrolysis system ( Guo et al, 2022 ). Therefore, the development of highly active OER electrocatalysts is one of the most important steps to improve the efficiency of the water electrolysis system and replace fossil fuels with hydrogen.…”

FeP-CoP Nanocubes In Situ Grown on Ti3C2Tx MXene as Efficient Electrocatalysts for the Oxygen Evolution Reaction

“…71-2262) emerge, despite their low crystallinity (Figure b) . According to previous reports, low crystallinity resulting from the low-temperature phosphorization process provides abundant dangling bonds and coordinately unsaturated atoms, which may increase the amount of active sites to promote the OER process. − Note that the characteristic peak of Ti 3 C 2 T x MXene at 7° is unobservable in the XRD patterns of Fe-Co PBA/Ti 3 C 2 T x - y and FeP-CoP/Ti 3 C 2 T x - y (Figure S2). Amounts of in situ grown PBA cubes prevent the stacking of Ti 3 C 2 T x MXene, and thus the characteristic peak stemming from the stacking structure of Ti 3 C 2 T x MXene layers disappears. , …”