Reconstructed Water Oxidation Electrocatalysts: The Impact of Surface Dynamics on Intrinsic Activities

Abstract

Electroreduction of small molecules such as H2O, CO2, and N2 for producing clean fuels or valuable chemicals provides a sustainable approach to meet the increasing global energy demands and to alleviate the concern on climate change resulting from fossil fuel consumption. On the path to implement this purpose, however, several scientific hurdles remain, one of which is the low energy efficiency due to the sluggish kinetics of the paired oxygen evolution reaction (OER). In response, it is highly desirable to synthesize high‐performance and cost‐effective OER electrocatalysts. Recent advances have witnessed surface reconstruction engineering as a salient tool to significantly improve the catalytic performance of OER electrocatalysts. In this review, recent progress on the reconstructed OER electrocatalysts and future opportunities are discussed. A brief introduction of the fundamentals of OER and the experimental approaches for generating and characterizing the reconstructed active sites in OER nanocatalysts are given first, followed by an expanded discussion of recent advances on the reconstructed OER electrocatalysts with improved activities, with a particular emphasis on understanding the correlation between surface dynamics and activities. Finally, a prospect for clean future energy communities harnessing surface reconstruction‐promoted electrochemical water oxidation will be provided.

Delivering the Full Potential of Oxygen Evolving Electrocatalyst by Conditioning Electrolytes at Near‐Neutral pH

“…In what follows, with the Tafel slope and the reaction order, the rate expression of the OER is elucidated. Regarding the reaction mechanism, previous literatures proposed two different OER mechanisms, that is, lattice‐oxygen‐mediated mechanism (LOM) and adsorbate evolution mechanism (AEM) [60,61] . In LOM, the lattice oxygen of electrocatalysts directly participates in the OER, and several reaction pathways involving different oxidation states of the metal site were proposed [62–64] .…”

“…Provided that many previous studies considered AEM to interpret the OER mechanism, [23,28,39,61] our present study herein also adopted the AEM. In this case, oxygen gas product is originated from absorbed H 2 O molecule, [60] and the oxidation of the H 2 O is considered to proceed via the following elementary steps [Eqs. (6)–]: [23,28,39,61] …”

Comprehensive Understandings into Complete Reconstruction of Precatalysts: Synthesis, Applications, and Characterizations

“…It should be noteworthy that a few reviews have been reported but mainly focus on surface reconstruction. [ 18–21 ] To the best of our knowledge, the summaries on complete reconstruction, especially its fundamental understandings, advantages and features of completely reconstructed catalysts, design principles/strategies, extensive electrocatalysis applications and establishment of reconstruction–performance correlation, as well as advanced characterizations, have not yet been reviewed comprehensively.…”

Tuning Reconstruction Level of Precatalysts to Design Advanced Oxygen Evolution Electrocatalysts

“…In addition, factors that affect the reaction conditions such as the concentration of the electrolyte, the applied potential, and the temperature will also affect the degree of surface change [ 56 , 85 ]. Thus, much effort has been devoted to exploring advanced OER electrocatalysts based on surface reconstruction [ 63 , 79 , 86 , 87 ].…”

“…The parameters of phase/electronic/geometrical structures, oxidation/spin states, and the morphology should be systemically considered [ 53 , 79 , 89 , 90 , 91 , 92 , 93 ]. Furthermore, in situ/operando spectroscopic techniques are crucial to identify the actual active species, providing greater insights into the relationship between the structure and activity of the studied catalysts [ 45 , 75 , 82 , 87 , 94 , 95 , 96 , 97 , 98 ].…”