Room-temperature volatile organosulfurs for synthesis of hierarchical Cu7S4 hollow nanotubelets for photodegradation of organic pollutants

Abstract

Herein, a novel, eco-friendly and sustainable green approach has developed for synthesis of uniform hollow Cu₇S₄ nanotubes on Cu foam using volatile organosulfur compounds of Allium Sativum L for photocatalytic of organic pollutants. This novel method facilitates sulfurization of Cu-foam without the need for surfactants (i.e regent free) at room temperature, resulting in Cu₇S₄ with unique hollow nanotubelets surface. The scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were employed to analysis the morphology, composition, structural phase and chemical states of the obtained sample. The N₂ adsorption-desorption isotherm depicts the Brunauer-Emmett–Teller (BET) surface area of Cu₇S₄ hollow nanotubelets is about 7.2 m² g⁻¹ with a pore size distribution of 46.89 nm. The obtained Cu₇S₄@Cu-foam was applied for degradation of methylene blue (MB) and methyl orange (MO) pollutants under visible light irradiation and exhibited an enhanced photocatalytic activity. The pseudo first order degradation kinetics rates for MB and MO are found to be 0.012 and 0.0098 min⁻¹, respectively. The scavenger studies indicated that the hydroxyl radicals (^•OH) and holes (h⁺) active species are mainly responsible for the degradation of MB and MO dyes. The higher photocatalytic activities are attributed to the enhanced light absorption, increased adsorption capacity, and better charge separation in the Cu₇S₄ catalyst.