Seamless architecture of porous carbon matrix decorated with Ta2O5 nanostructure-based recyclable photocatalytic cartridge for toxicity remediation of industrial dye effluents

Abstract

Dye waste management via renewable stratagem as well as understanding the nature of degraded products are highly essential for controlling the water purification process. Decoration of the photoactive heterostructure on top of a porous, chemically stable, nontoxic and rigid template is a real challenge for practical designing of low-cost cartridge for industrial waste management. Herein, the porous, high surface carbon-based Melamine Foam-Graphene-Carbon Nanotubes decorated Tantalum oxide (MF-Gr-CNTs-Ta2O5) heterostructure is successfully synthesized. The oxygen vacancies in Ta2O5lattice evident in X-ray Photoelectron Spectroscopy (XPS) analysis and facile interface in CNTs-Ta2O5observed in Transmission Electron Microscopy (TEM) imaging, promote the effective way of photogenerated charge carrier separation. The excellent photocatalytic performance is observed against Eriochrome Black T (EBT) with 95% of degradation efficiency within 100 min of photo exposure. The rate constant increases from 0.00624 to 0.03059 min-1for bare Ta2O5 to heterostructure, owing to faster kinetics involved in the generation of reactive oxygen species (ROS) for rapid photodegradation of dye. The effect of scavenger shows that superoxide radical participation is dominant in reaction kinetics with respect to other reactive species. The Total Organic Carbon (TOC) removal efficiency is achieved to be ∼ 93.45% which is remarkably high in photocatalytic degradation process. Liquid Chromatography-Mass Spectroscopy (LCMS) are performed to elucidate the non-toxic end-products evaluated via Toxicological analysis on glial cell line (C6) which shows cellular viability of 72% as compared to that of 38% for bare EBT (800 μg/ml).The photocatalyst has shown reusability till 8 cycles at a loss of ∼ 8% efficiency revealing the potential applicability towards developing cartridge technology. Knowing the porous and stable carbon-based heterostructure, a smart strategy has been adopted to demonstrate a filter-prototype setup. This study paves the way to design a cost-effective, reusable, cartridge material adopting an environmentally benign technique for waste-water purgation.