Synergy of the heterojunction and defects engineering in Zr-doped TbFeO3@g-C3N4 photo-nanocatalyst towards enhanced visible-light-driven antibiotics degradation and H2 production

Abstract

Environmental remediation and energy production are major concerns of the globe for sustainable development. Solar-driven photo nanocatalysts have shown great potential to be a suitable contender to solve these issues, however, their catalytic efficiency is the major concern which depends on the e⁻/h⁺ pair separation. The present study developed TbFe_0.95Zr_0.05O₃/g-C₃N₄ heterostructure employing facile hydrothermal methods to promote e⁻/h⁺ pair separation. Though, TbFe_0.95Zr_0.05O₃/g-C₃N₄ achieved the highest photo-degradation of 95.96 % for Norfloxacin (NOR) in 90 min, and 4864 μmol h⁻¹g⁻¹ of H₂ evolution in 4 h under simulated visible-light, with 3.3, 2.8 and 2.1 times higher efficiency than pristine and doped catalysts (TbFeO₃, g-C₃N₄ and TbFe_0.95Zr_0.05O₃). The creation of oxygen vacancies (OVs) by Zr⁴⁺ doping at Fe³⁺ sites through charge compensation may increase catalytic efficiency, confirmed through X-ray photoelectron spectroscopy (XPS), and optical properties through Raman, and photoluminescence spectroscopy (PL). The catalyst works well throughout four cycles (85.19 % for NOR in the 4^th cycle), demonstrating its chemical stability and cyclic potential. Thus, heterojunction and OVs synergistically enhance catalytic efficiency with higher activation in the visible solar spectrum and long e⁻/h⁺ charge separation lifetime.