Enhanced photocatalytic degradation of norfloxacin under visible light by immobilized and modified In2O3/TiO2 photocatalyst facilely synthesized by a novel polymeric precursor method

Ion co-doped photocatalysts with In 2 O 3 /TiO 2 heterostructure (In 2 O 3 /TiO 2 (m)) were prepared through a new polymeric precursor method. The In 2 O 3 /TiO 2 (m) precursor solution is of salient advantage in coating photocatalysts on various substrates and multiple modifications. The photocatalysts were facilely obtained after the calcination of precursors. Mass ratio of In/Ti was optimized according to their photocatalytic performances, and IT(m)-3 ( w In/Ti  = 3%, modified by N, B co-doping) showed the best photocatalytic activity. The band gap was successfully narrowed to 2.37 eV, and In 2 O 3 /TiO 2 heterostructure was successfully constructed in the photocatalysts. Visible light absorption and separation of photoexcited carriers were significantly enhanced. Under visible light, NOX (20 mg/L in the water) was 100% photodegraded in 10 min, with 100% TOC removed in 25 min. The IT(m)-3-loaded quartz fabrics (ITQ) also showed excellent photocatalytic performance. The photocatalytic activity of ITQ was repeatable and stable in 45 rounds of recycle without centrifugation. Synergetic effect of heterostructure and element doping was considered contributing to the outstanding photocatalysis performance. The polymeric precursor method proposed in this work showed great potential in large-scale preparation and application of immobilized photocatalysts. The synergetic improvement through co-modifications showed its proper compatibility with modifications.