Te4+ and Er3+ doped ZrO2 nanoparticles with enhanced photocatalytic, antibacterial activity and dielectric properties: A next generation of multifunctional material.

ABSTRACT

Amid rising water contamination from industrial sources, tackling toxic dyes and pathogens is critical. Photocatalysis offers a cost-effective and eco-friendly solution to this pressing challenges. Herein, we synthesized Te4+ and Er3+ doped ZrO2 photocatalysts through hydrothermal method and investigated their efficacy in degrading Congo red (CR) and pathogens under visible light. XRD and Raman Spectroscopy confirm monoclinic and tetragonal mixed-phases without any impurities. Doping-induced defects, reduced crystalline diameter, high surface area, modified bandgap (2.95 eV), photoluminescence quenching, coupled with interfacial polarization, contribute to EZO's excellent dielectric response (1.149 × 106), for achieving remarkable photocatalytic activity, verified by photoelectrochemical measurements, LC-MS and phytotoxicity analysis. Under optimal conditions, EZO achieves 99% CR degradation within 100 min (TOC 79.9%), surpassing ZO (77%) and TZO (84%). Catalyst dosages, dye concentrations, and solution pH effect on EZO's photocatalytic performance are systematically assessed. Scavenging experiment emphasized the pivotal role of · OH in CR degradation with 96.4% efficiency after 4 cycles, affirming its remarkable stability. Moreover, EZO demonstrates ROS-mediated antibacterial activity against E. faecalis and E. coli bacteria under visible light, achieving >97% and >94% inhibition rate with an inhibition zone > 3 mm. Hence, the nanoparticle's dual action offers a practical solution for treating contaminated wastewater, ensuring safe irrigation.