Copper Doping of CdS Nanoflakes and Nanoflowers for Efficient Photocatalytic Degradation of MB and MV Dyes

Abstract

Nanoflowers and flakes CdS films were produced on glass substrates using a hydrothermal technique for 2 h at 150 °C utilizing basic ingredients. The films' structural, morphological, optical, and photocatalytic characteristics were investigated at various concentrations of 1%, 2%, 3%, 4%, and 5% Cu-doping. X-Ray diffraction investigations reveal that un-doped and doping films are polycrystalline, having hexagonal and cubic crystal formations. The films have highly preferred orientation along H(002)/C(111). The crystallite size of the deposited samples decreased from 10.7 to 5.2 nm as the Cu-doping concentration increased. The films' atomic force microscope imagery revealed morphological changes and an increase in surface roughness from 4.58 to 18 nm. The field-emission scanning electron microscopy micrographs showed shape development of the nanoflakes in the presence of copper. The transmittance and energy gap were measured and estimated at various doping concentrations. The results demonstrate that increasing the concentration of Cu doping reduced the energy gap from 2.38 to 1.98 eV. The Cu-doped cadmium sulfide films have shown photocatalytic activity for the degradation of methyl blue (MB) and methyl violet (MV) dyes due to their enhanced size, reduced energy gap, and efficient separation of charging characteristics. Also, 5% Cu:CdS sample showed high degradation up to 89% of the MB and 97% of the MV were degraded in 260 min.