Facile synthesis of Pd nanoparticles dispersed polypyrrole-carbon black/NiO nanocomposite with enhanced photocatalytic degradation of colored and colorless organic pollutants

Abstract

Creation and designing of efficient visible-light responsive photocatalysts requires highly precise and extremely determined efforts in order to obtain material with promising properties and efficient transfer of charge carriers. In this work, we aim to develop and manufacture a distinct visible light photocatalyst consisting of NiO nanostructures, polypyrrole doped carbon black (PPyC) and Pd nanoparticles for wastewater treatment. The Pd NPs and PPyC doped NiO trio photocatalyst was developed via simple ultrasonication and photoreduction methods. XRD analysis showed that NiO has crystalline face centered cubic structure while the successful development of ternary photocatalyst was smoothly confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FTIR) studies. Transmission electron microscopy (TEM) images showed that NiO possessed fine irregular shape particles with size ranging from 20 to 50 nm grown abundantly in huge density, while the PPyC exhibited beads shape structures interconnected with each other giving chain like appearance. The diffuse reflectance UV–vis spectra showed red shift and lowering in bandgap upon Pd and PPyC doping. The newly produced Pd-PPyC@NiO photocatalyst has been exploited for the photocatalytic removal of colorless insecticide imidacloprid and colored methylene blue (MB) dye under visible light irradiation. The newly created Pd-PPyC@NiO photocatalyst removed 96.0% of imidacloprid just in 20 min representing ⁓ 3 times more efficient than bare NiO. Furthermore, Pd-PPyC@NiO photocatalyst was exceptionally well towards the destruction of MB under same visible light source, indicating its potential use in photocatalysis.