Ru Coordinated ZnIn2S4 Triggers Local Lattice-Strain Engineering to Endow High-Efficiency Electrocatalyst for Advanced Zn-Air Batteries

Developing bifunctional electrocatalysts is the primary challenge to improve the reaction efficiency of zinc-air batteries. Lattice-strain engineering constructs high-efficiency oxygen redox catalysts by tuning the physicochemical properties of nanomaterials. However, the randomness and complexity of lattice mismatch make it difficult to effectively identify the structure-activity relationship between the strain and catalyst. Herein, a strategy of Ru triggered partial coordination environment mutation of ZnIn2S4 (R(0.1)ZIS) to regulate the d-band center of catalytic sites is provided, which dramatically activates intrinsic activity and accelerates electron transfer. Density functional theory calculations and system characterizations reveal that local lattice strain causes anti-bonding orbital to occupy more electrons and narrower bandwidth, reduce the migration energy barrier of *OH deprotonation and optimize the adsorption/desorption process of oxygen-containing intermediates, thus demonstrating extraordinary catalytic performance in oxygen reduction reaction and oxygen evolution reaction. Expectedly, the R(0.1)ZIS-based cell delivers the open circuit potential of 1.587 V almost identical to the theoretical voltage, and an ultralow voltage gap of 0.71 V after undergoing 262 h operation. This work offers a promising avenue for building lattice-strain engineering to realize robust bifunctional electrocatalysts.

Automated summary

By regulating the partial coordination environment mutation of catalytic sites, the intrinsic activity of the catalyst can be activated and electron transfer can be accelerated, achieving efficient oxygen reduction reaction. This research provides a promising avenue for constructing lattice-strain engineering.