Scalable NixSy@diatomite core-shell architectures with thermodynamic stability for bifunctional microwave absorption and oxygen evolution catalysis

Scalable synthesis of hierarchical architectures with targeted interface engineering enables dual-functional materials for efficient microwave absorption and oxygen evolution reaction (OER). A bio-template-directed sulfurization strategy constructs Ni x S y @diatomite core-shell hybrids. Sulfur-modulated interfaces enhance both electromagnetic dissipation and electrocatalytic kinetics. The porous diatomite/Ni-S gradient structure achieves ideal impedance matching and multi-phase polarization, yielding outstanding microwave absorption: 93.5 dB minimum reflection loss at 15.86 GHz and an ultra-wide 6.66 GHz bandwidth (covering C/Ku bands). Moreover, it exhibits superior OER performance with a low overpotential (258 mV@10 mA cm −2 ) and Tafel slope of 82.62 mV dec −1 in alkaline solution, outperforming the commercial RuO 2 . High electrochemical surface area further supports enhanced kinetics. Crucially, bio-inspired design ensures thermodynamic stability (<1 % mass loss, 20–400 °C) and durability for high performance of microwave adsorption, also bionic architecture improves the active sites density of the electrode to enhance water splitting. This work bridges scalable synthesis, interfacial optimization, and dual functionality for next-generation electromagnetic protection and energy conversion systems.