N-doped MoS₂@indium tin oxide (ITO) core–shell nanowires for high-performance ammonium ion micro-supercapacitor.

This article focuses on enhancing ammonium ion (NH4⁺) aqueous supercapacitors by developing nitrogen (N) plasma-doped molybdenum disulfide (MoS2) coated on indium tin oxide nanowires (MoS2@ITO NWs) as electrode materials. The N plasma doping expands the interlayer spacing of MoS2 and improves its electronic conductivity, facilitating reversible NH4⁺ ion insertion/extraction and significantly increasing areal capacitance from 78.6 to 161.8 mF cm⁻² at 1 mA cm⁻², with over 89% capacity retention after 10,000 cycles. Electrochemical tests demonstrate that these N-doped electrodes exhibit superior rate capability, lower charge transfer resistance, and enhanced energy density (43.8 μWh cm⁻² at 704.3 μW cm⁻²) compared to undoped counterparts, highlighting their potential for next-generation, cost-effective, safe, and environmentally friendly micro-supercapacitors.