One-pot combustion fabrication of grain-like mesoporous intra-heterostructure BixOyClz nanophotocatalyst with substantial solar-light-driven degradation of antibiotic ofloxacin: influence of various fuels

Abstract

In the present study, a Bi_xO_yCl_z nanophotocatalyst was synthesized via one-pot solution combustion synthesis using various fuels such as glycine, urea, citric acid and sorbitol. Characterization of the photocatalyst was carried out by XRD, FESEM, TEM, PSD, EDX, BET–BJH, UV-vis DRS, PL and pH_pzc techniques. The results revealed that a grain-like mesoporous Bi_xO_yCl_z nanophotocatalyst consisting of BiOCl and Bi₂₄O₃₁Cl₁₀ was successfully synthesized using sorbitol. The fabricated nanophotocatalyst was used in the degradation of the antibiotic ofloxacin under simulated solar light. The highest efficiency (82.5%) and reaction rate (k = 0.017 min⁻¹) in the photodegradation of the antibiotic ofloxacin were achieved with the grain-like mesoporous nanophotocatalyst synthesized using sorbitol. Studies of the effects of operational parameters such as the pH, catalyst loading and antibiotic concentration showed an increase in the photocatalytic performance of Bi_xO_yCl_z (sorbitol) at a low concentration of the pollutant, at the optimal catalyst dosage (5 g L⁻¹) and in acidic media. High stability after five reaction cycles was observed for the Bi_xO_yCl_z (sorbitol) nanophotocatalyst. Moreover, a reaction mechanism was suggested for the photodegradation of the antibiotic ofloxacin over Bi_xO_yCl_z (sorbitol).