Mesoporous-mixed-phase of hierarchical bismuth oxychlorides nanophotocatalyst with enhanced photocatalytic application in treatment of antibiotic effluents

Abstract

The mesoporous-mixed-phase of hierarchical bismuth rich-bismuth oxychlorides nanophotocatalysts were synthesized using a facile one-pot sorbitol-nitrate solution auto-combustion synthesis and without additional heat and other post-treatments. The efficacies of the sorbitol as fuel to oxidizer ratio which is called the fuel to oxidizer ratio were studied on the behaviour of combustion, type and weighted quantity of phases and other remarkable features via X-ray diffraction, field-emission scanning electron microscopy, particle size distribution, Energy-dispersive X-ray spectroscopy-Dot mapping, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda and Ultraviolet–Visible diffuse reflectance spectroscopy analyses. Moreover, the solar-light-driven heterogeneous photocatalytic performance of nanophotocatalysts fabricated was evaluated in the antibiotic ofloxacin degradation as an emerging contaminant. The bismuth rich-bismuth oxychlorides synthesized with fuel ratio of 1, as the grain-like mixed-phase with an intra-heterojunction between 59% BiOCl and 41% Bi24O31Cl10 indicated the higher activity (at about 80% after 120 min irradiation) and degradation rate (0.018 min−1) as well as substantial stability after five cycles with high total open pore volume of 0.189 cm3/g, specific surface area of 93 m2/g, meso-structure of pores with average pore width of 11 nm, absorption of much light, appropriate band gap (2.69 eV), and the diminution of incorporation rate of electrons and holes. The mesoporous-mixed-phase bismuth rich-bismuth oxychlorides is a promising solar-light-driven nanophotocatalyst for organics photo-destruction.