Bioinspired trimesic acid anchored electrocatalysts with unique static and dynamic compatibility for enhanced water oxidation

Abstract

Layered double hydroxides are promising candidates for the electrocatalytic oxygen evolution reaction. Unfortunately, their catalytic kinetics and long-term stabilities are far from satisfactory compared to those of rare metals. Here, we investigate the durability of nickel-iron layered double hydroxides and show that ablation of the lamellar structure due to metal dissolution is the cause of the decreased stability. Inspired by the amino acid residues in photosystem II, we report a strategy using trimesic acid anchors to prepare the subsize nickel-iron layered double hydroxides with kinetics, activity and stability superior to those of commercial catalysts. Fundamental investigations through operando spectroscopy and theoretical calculations reveal that the superaerophobic surface facilitates prompt release of the generated O2 bubbles, and protects the structure of the catalyst. Coupling between the metals and coordinated carboxylates via C‒O‒Fe bonding prevents dissolution of the metal species, which stabilizes the electronic structure by static coordination. In addition, the uncoordinated carboxylates formed by dynamic evolution during oxygen evolution reaction serve as proton ferries to accelerate the oxygen evolution reaction kinetics. This work offers a promising way to achieve breakthroughs in oxygen evolution reaction stability and dynamic performance by introducing functional ligands with static and dynamic compatibilities.

Bubbles Management for Enhanced Catalytic Water Splitting Performance

“…The smaller nanoplatelet surfaces of su-nfe-ldh(TA)@cp were much rougher and exhibited superhydrophilicity. These apparent changes suggest that the insertion layer formed by cyanuric acid increases the rate of electrolyte diffusion on the surface and between the layers [124]. In addition, the cavitation effect due to bubble rupture can severely damage the nanostructures, and the evolution of bubbles on the electrode surface affects the stability of the structure [125].…”

“…(d-f) In situ dete tion of precipitation behavior of O2 on NiFe LDH@cp, NiFe-LDH(TA)@cp, and SU-NiF LDH(TA)@cp at 10 mAcm −2 , respectively. Reproduced with permission from[124], © 2023 Natu Publishing Group.…”

Accelerated Proton Transfer in Asymmetric Active Units for Sustainable Acidic Oxygen Evolution Reaction

“…18−20 It has been demonstrated that the OER activity of metal oxides can be significantly enhanced by accelerating proton transfer, thereby facilitating the CPET process. 21,22 Expediting the deprotonation of oxo-intermediates is a promising direction that improves the OER kinetics of Rubased catalysts in acidic electrolytes. 23−25 However, in low pH environments, the deprotonation process of intermediates is influenced by the proton-rich conditions, leading to proton accumulation on the catalyst surface and the corrosion of active sites.…”