Ultrasonically derived WSe₂ nanostructure embedded MXene hybrid composites for supercapacitors and hydrogen evolution reactions

Two-dimensional (2D) transition metal chalcogenides (TMDCs) and carbide have validated boundless prospective as multi-functional constituents for high performance energy storing and/or conversion devices. However, pure TMDCs exhibit poor performance for electrochemical applications due to low electrical conductivity, scarce electrochemically active edges and inadequate cycling stability. Therefore, this paper fabricated MXene/WSe₂ hybrids with strong interfacial interactions and conductivities using a one-step chemical reaction as electrodes for supercapacitors and hydrogen evolution. Fabricated supercapacitors achieved high specific capacitance = 840 F g⁻¹ at 2 A g⁻¹, with symmetric capacitance = 246 F g⁻¹ at 2 A g⁻¹ for MXene/WSe₂ hybrids. Hydrogen evolution achieved low overpotentials = 76 and 62 mV to drive 10 mA cm⁻² current with small Tafel slopes = 78 and 84 mV.dec⁻¹ in acid and base media, respectively. 2D and 2D hybrid WSe₂ nanoparticle composite embedded MXene scaffolds achieved excellent electron/ion intercalation owing to its distinctive 2D-layered structure, increasing interlayer spacing and retaining large electrode/electrolyte contact to enhance efficiency. Two-dimensional TMDCs/MXene composites were verified as potentially efficient electrode materials for energy storing and exchange uses.