Enhanced adsorption-photocatalysis synergy and stability of polypropylene photocatalytic floating ball benefitted from click chemistry connection

Floating photocatalytic materials provide an effective way for the practical application of photocatalytic technology. In this study, a highly efficient and stable polypropylene photocatalytic floating ball (CC-P25/BC@PP) was designed and synthesized via firstly coupling Degussa P25 with biochar (BC) through click chemical reaction, followed by loading the composites on PP hollow ball with help of titanate coupling agent. Statistical analysis found that, compared to the PP ball decorated with simple P25/BC mixture (denoted as Mix-P25/BC@PP), click chemistry connection not only significantly increased the effective loading limit of P25/BC composites on PP ball, but also enhanced the adsorption-photocatalysis synergy between TiO 2 and biochar. As a result, the degradation rate constant of ciprofloxacin (CIP) was nearly doubled. Moreover, due to the strengthened connection between P25/BC composite with PP ball, stability of CC-P25/BC@PP was improved significantly, and the shedding rate of active ingredients from PP ball during cycling experiment, acid/alkali soak and ultrasonic oscillation were suppressed 3.80–6.71 times compared to Mix-P25/BC@PP. Therefore, the highly efficient and stable PP photocatalytic floating ball based on click chemistry reaction showed strong practical application potentials.