Advancing extreme-temperature-tolerant zinc–air batteries through photothermal transition metal sulfide heterostructures†

The development of cost-effective, high-performance bifunctional oxygen catalysts shows significant potential for the commercialization of zinc–air batteries (ZABs). In this study, photothermal electrocatalysts consisting of NiCo₂S₄@NiFe layered double hydroxides on a graphene oxide (NiCo₂S₄@NiFe LDH/N-rGO) were crafted. The NiCo₂S₄@NiFe LDH/N-rGO electrocatalyst displayed remarkable bifunctional activity with an impressive ΔE value of 0.636 V under the influence of photothermal effects, far exceeding most advanced systems (generally >0.68 V). At a high current density of 25 mA cm⁻², the NiCo₂S₄@NiFe LDH/N-rGO-based ZAB exhibited an impressive cycling performance, reaching 3410 cycles and extending further to an extraordinary 8285 cycles under illumination conditions. Moreover, when considering flexible all-solid-state ZABs, photothermally-assisted rechargeable batteries displayed outstanding attributes, including exceptional maximum power density (e.g., 151.7 mW cm⁻² at 25 °C), remarkable cycle stability (e.g., over 3480 cycles at −40 °C), and remarkable flexibility, spanning from high temperature (60 °C) to extremely low temperature (−40 °C). Through operando Raman and simulation investigation, it was revealed that the photothermal effect facilitates the generation of oxyhydroxide, underscoring the beneficial impact of light on the electrocatalysis.