Synthesis of Cu-WO3-CNT nanocomposite and its electrochemical and photocatalytic properties: Application for Cr(VI) removal from aqueous solution

The goal of this study was to create a potent photocatalyst for the removal of hexavalent chromium (Cr(VI)) from water and wastewater. This was done by synthesizing a Cu nanoparticle-WO3-CNT nanocomposite (Cu-WO3-CNTs). The Cu-WO3-CNTs were made using the precipitation and calcination processes. Cu and WO3 nanoparticles were successfully anchored to the surface of CNTs, according to morphological and structural studies of photocatalysts conducted using FE-SEM, XRD, and EDS analysis. The optical band gap energies of WO3, WO3-CNTs, and Cu-WO3-CNTs nanocomposite were found to be 2.91, 2.79, and 2.62 eV, respectively. Based on research using UV–vis absorption spectroscopy. According to EIS investigations, Cu-WO3 had a synergistic impact on the surface of CNTs, accelerating the electron transport path and helpfully inhibiting the recombination of electron-hole pairs in the Cu-WO3-CNTs sample. The entire removal of Cr(VI) was achieved for WO3, WO3-CNTs, and Cu-WO3-CNT nanocomposites, respectively, after 110, 60, and 48 min of sunshine exposure, according to the results of the investigation on the photocatalytic activity for the removal of 50 mg/L Cr(VI) solution. The ability of Cu-WO3-CNTs nanocomposite structures for reducing Cr(VI) in industrial wastewater was investigated in a Cr(VI) solution that was made using industrial wastewater, and the results showed that Cr(VI) could be reduced effectively by photocatalysis in the presence of Cu-WO3-CNTs nanocomposite photocatalyst.