Fabrication of high-performance ZIF-8/SnO₂@RuO₂ integrated electrode materials cooperative mechanisms for superior energy storage efficiency and hydrogen evolution reaction

This study presents the development of a unique 2D ZIF-8/SnO₂@RuO₂ composite utilizing the hydrothermal process, for dual applications in energy storage devices and HER. We explain a straightforward approach to change ZIF-8 and Tin (IV) oxide (SnO₂) utilizing Ruthenium (IV) oxide (RuO₂) through a regulated hydrothermal technique, devoid of a template, to produce ZIF-8/SnO₂@RuO₂ composites. Our approach prevents the accumulation of ZIF-8/SnO₂@RuO₂, enhances the usage of active materials, and increases the exposure of active sites, facilitating electron transmission. Due to its distinctive hierarchical architecture, ZIF-8/SnO₂@RuO₂ possesses a specific surface area (SSA) of 163.61 m²g^-¹, and the ZIF-8/SnO₂@RuO₂//AC electrode proved a Q_s of 280 C/g at 1 A/g, the highest value among MOF based combined. An asymmetric supercapacitor (ASC) constructed with ZIF-8/SnO₂@RuO₂ as the electrodes exhibited excellent capacitive performance a broad potential range of 0–0.7 V. ZIF-8 functions as a resilient framework with a substantial surface area, SnO₂ superior electrochemical stability. RuO₂, employed as a dopant, markedly improves the composite catalytic process and charge transport characteristics. The ASC displayed a high E_d of 74.6 Wh/kg, a P_d of 1600 W/kg, and commendable cycling stability and adaptability. The RuO₂-doped combined demonstrates an overpotential of 125 mV at 3 mA/cm² for HER applications, accompanied by a Tafel slope of 55.6 mV/dec, signifying very efficient hydrogen production. The material demonstrates exceptional cyclic stability, maintaining 90.2 % of its capacity after 1000 cycles, and exhibits a high coulombic efficiency above 95.6 %, underscoring its resilience for prolonged uses. The composite demonstrates consistent performance under an RHE of −3.5 V, underscoring its durability for HER. Integrating 2D architecture, RuO₂ doping, and enhanced electrochemical performance positions ZIF-8/SnO₂@RuO₂ as a distinctive and promising material for advanced energy storage and hydrogen production technologies.