Frustrated Lewis Pair Mediated f-p-d Orbital Coupling: Achieving Selective Seawater Oxidation and Breaking *OH and *OOH Scaling Relationship

Angew Chem Int Ed Engl. 2024 Oct 11:e202414721. doi: 10.1002/anie.202414721. Online ahead of print.

Abstract

The development of oxygen evolution reaction (OER) electrocatalyst for seawater electrolysis plays a crucial role in producing renewable hydrogen energy. However, during the seawater electrolysis process, the anode inevitably undergoes chloride oxidation reaction (ClOR) due to Cl- adsorption, making the seawater electrolysis process difficult to sustain. Inspired by the selective permeability of cell membranes, we propose a biomimetic design of frustrated Lewis pairs (FLPs) layers for selective seawater oxidation. Combining experimental results and molecular dynamics simulations, it has been demonstrated that cerium dioxide layers with FLPs sites can decompose water molecules, capture hydroxyl anions, and repel chloride ions simultaneously. DFT theoretical analysis indicates that the FLP sites regulate the Ce 4 f-O 2p-Ni 3d gradient orbital coupling, providing additional oxygen non-bonding (ONB) to stabilize the Ni-O bond and optimize the adsorption strength of intermediates, thereby breaking the *OH and *OOH scaling relationship. The assembled anion exchange membrane electrolyzers exhibit an efficiency of 95.7 % at a current density of 0.1 A cm-2 and can stably operate for 250 hours at a current density of 0.2 A cm-2.

Keywords: Cl− resistance; Frustrated Lewis pairs; Orbital coupling; Seawater electrolysis.