Reductive debromination of tetrabromobisphenol A by tailored carbon nitride Fe/Cu nanocomposites under an oxic condition

Abstract

Supple exfoliated graphitic carbon nitride (C3N4) with high electron transport and photoactive properties are utilized as catalyst supports for environmental remediation. This study synthesized Fe/Cu bimetallic catalyst decorated on to the C3N4 matrix as an excellent support for complete debromination of tetrabromobisphenol A (TBBPA), one emerging contaminant and also one brominated flame retardant, under oxic conditions. Fe/Cu bimetallic nanoparticles are deposited on few layered thick C3N4 (CN) matrices. XRD, SEM-EDS, EPMA and surface area analysis show that as synthesized Fe/Cu@CN nanocomposites contain well distributed zerovalent iron (ZVI) and Cu nanoparticles (NPs) with enhanced surface area. Fe/Cu@CN nanocomposites showed catalytic degradation of TBBPA under ambient conditions and byproducts were analyzed and identified by HPLC and GC-MS respectively. Various factors such as catalyst dose, initial TBBPA concentration, and initial pH condition were executed to optimize the best conditions for the rapid and complete degradation of TBBPA. The highest degradation rate of 0.191 min−1 was recorded by Fe/Cu@CN nanocomposites under neutral pH and ambient conditions. Furthermore, the electrochemical impedance spectroscopic analysis revealed that C3N4 matrix plays a crucial role during the degradation process by providing large surface area, excellent electron transportability for wrapped Fe/Cu bimetallic NPs, resulting in reduced inherent iron corrosion. This study discloses that C3N4 is a promising catalyst support with restricted iron corrosion paving the way to tailor the Fe0 based nanocomposites in elucidation of wide variety of catalytic and photocatalytic reduction applications.