Synthesis of an Ag3PO4/Nb2O5 Photocatalyst for the Degradation of Dye

Defect and Heterostructure engineering assisted S-scheme Nb2O5 nanosystems-based solutions for environmental pollution and energy conversion

This review explores the crystallographic versatility of niobium pentoxide (Nb2O5) at the nanoscale, showcasing enhanced catalytic efficiency for cutting-edge sustainable energy and environmental applications. The synthesis strategies explored encompass defect engineering, doping engineering, s-scheme formation, and heterojunction engineering to fine-tune the physicochemical attributes of diverse dimensional (0-D, 1-D, 2-D, and 3-D) Nb2O5 nanosystems as per targeted application. In addressing escalating environmental challenges, Nb2O5 emerges as a semiconductor photocatalyst with transformative potential, spanning applications from dye degradation to antibiotic and metal removal. Beyond its environmental impact, Nb2O5 is pivotal in sustainable energy applications, specifically in carbon dioxide and hydrogen conversion. However, challenges such as limited light absorption efficiency and scalability in production methods prompt the need for targeted research endeavors. The review details the state-of-the-art Nb2O5 nanosystems engineering, tuning their physicochemical properties employing material engineering, and their high catalytic performance in environment remediation and energy generation. It outlines challenges, potential mitigation strategies, and prospects, urging for developing greener synthesis routes, advanced charge transfer techniques, targeted optimization for specific pollutants, and application for micro/nano plastics photocatalytic reduction. As researchers and environmental stewards collaborate, Nb2O5 stands poised at the intersection of environmental remediation, energy harvesting, and nanomaterial advancements, offering a beacon of progress toward a cleaner, more sustainable future.

Perovskite LaNiO3/Ag3PO4 heterojunction photocatalyst for the degradation of dyes

Pristine lanthanum nickelate (LaNiO₃), silver phosphate (Ag₃PO₄) and perovskite lanthanum nickelate silver phosphate composites (LaNiO₃/Ag₃PO₄) were prepared using the facile hydrothermal method. Three composites were synthesized by varying the percentage of LaNiO₃ in Ag₃PO₄. The physical properties of as-prepared samples were studied by powder X-ray diffraction (pXRD), Fourier-transform infrared (FT-IR), Scanning electron microscopy (SEM) and Energy-dispersive X-ray (EDX). Among all synthesized photocatalysts, 5%LaNiO₃/Ag₃PO₄ composite has been proved to be an excellent visible light photocatalyst for the degradation of dyes i.e., rhodamine B (RhB) and methyl orange (MO). The photocatalytic activity and stability of Ag₃PO₄ were also enhanced by introducing LaNiO₃ in Ag₃PO₄ heterojunction formation. Complete photodegradation of 50 mg/L of RhB and MO solutions using 25 mg of 5%LaNiO₃/Ag₃PO₄ photocatalyst was observed in just 20 min. Photodegradation of RhB and MO using 5%LaNiO₃/Ag₃PO₄ catalyst follows first-order kinetics with rate constants of 0.213 and 0.1804 min^-1, respectively. Perovskite LaNiO₃/Ag₃PO₄ photocatalyst showed the highest stability up to five cycles. The photodegradation mechanism suggests that the holes ( h ⁺) and superoxide anion radicals O 2   • - plays a main role in the dye degradation of RhB and MO.