Designing of High-Performance MnNiS@MXene Hybrid Electrode for Energy Storage and Photoelectrochemical Applications

The overconsumption of fossil fuels is leading to worsening environmental damage, making the generation of clean, renewable energy an absolute necessity. Two common components of electrochemical energy storage (EES) devices are batteries and supercapacitors (SCs), which are among the most promising answers to the worldwide energy issue. In this study, we introduce an exceptionally efficient electrode material for supercapacitors, composed of a hydrothermally synthesized composite known as MnNiS@MXene. We utilized XRD, SEM, and BET to analyze the material’s crystallinity, morphology, and surface area. The Qs of MnNiS@MXene was a remarkable 1189.98 C/g or 1983.3 F/g at 2 A/g under three electrode assemblies in 1 M KOH electrolyte solution. Activated carbon was used as the negative electrode, while MnNiS@MXene served as the positive electrode in the assembled supercapattery device (MnNiS@MXene//AC). This device showed exceptional performance, a specific capacity of 307.18 C/g, a power density of 1142.61 W/kg, and an energy density of 34.79 Wh/kg. Additionally, cyclic durability was evaluated through 7000 cycles of charging/discharging, demonstrating that it maintained approximately 87.57% of its original capacity. The successful integration of these materials can lead to electrodes with superior energy storage capabilities and efficient photoelectrochemical performance. The aforementioned findings suggest that MnNiS@MXene exhibits promising potential as an electrode material for forthcoming energy storage systems.