Energy and environmental applications of ultrasonically sulfur doped copper-nickel hydroxides with heterostructures

Abstract

A series of sulfur doped copper-nickel hydroxides with heterojunctions were successfully fabricated on nickel foam by adjusting thiourea volume via a facile sonochemical pathway. The effect of volume of thiourea on the final morphology and chemical composition of the hybrids were also investigated by field-emission scanning electron microscopy, and X-ray photoelectron spectroscopy analyses. Furthermore, the electrochemical performance and catalytic activity of the as-obtained hybrids were also investigated. Among the tested electrode, the hybrid material fabricated using 6 ml of thiourea (TU-6) showed outstanding electrochemical properties comprising a high specific capacitance of about 2708 F g−1 at 5 A g−1. In addition, the TU-6 hybrid (catalyst) material displayed remarkable reductive degradation ability towards azo dyes viz., methyl orange (within 8 min) and congo red (within 20 min) in the presence of sodium borohydride (reducing agent) with fast kinetics and good reproducibility, respectively. The exceptional electrochemical performance and excellent catalytic activity of TU-6 hybrid electrode may be attributed to the formation of catalytically active sulfur doped copper-nickel hydroxides (CuS/Ni3S2/NiOOH) three-interface synergistic effect, and unique porous micro-rosette-like texture which increased the diffusion rate and adsorption capacity. The adopted strategy is a simple and generic way for material fabrication to solve the energy and environmental problems.