Flexible And Recyclable PPy‐TiO2@WO3 Photocatalyst Supported By Cellulose Aerogel Beads

Abstract

AbstractPolypyrrole (PPy)‐TiO2@WO3 catalyst supposed by cellulose aerogel beads was synthesized using inverse suspension crosslinking approach. The resulting particles were small and well‐crystallized according to scanning and transmission electron microscopies. The efficiency of the resulting photocatalysis was tested relative to degradation of tetraethylated rhodamine (RhB), which was judged by solution discoloration and also by RhB content decrease. Excellent photocatalytic activity of cellulose aerogel (CE)‐PPy‐TiO2@WO3 beads was attributed to the synergy between TiO2 and WO3, which widened material absorption bandedge and improved migration efficiency of photogenerated electrons and holes. Presence of black PPy widened absorption band edge further promoting photogenerated electron and hole separation. More importantly, presence of macro‐porous CE increased optical absorption of this composite photocatalyst and helped photocatalyst to retain its structural integrity during repeated recycling. If needed, photocatalyst can be easily removed from the reaction solution to prevent secondary pollution. Our complex CE‐PPy‐TiO2@WO3 bead‐like photocatalyst also demonstrated good mechanical strength and excellent flexibility, which allowed it to be folded and bent. We proposed photocatalytic mechanisms responsible for processes involving CE‐PPy‐TiO2@WO3 beads, understanding of which will help to improve the photocatalytic performance of this material even further. Catalysts based on CE‐PPy‐TiO2@WO3 beads can be used in complex environments and small spaces because of their flexibility and recyclability. It might be especially useful for applications in difficult‐to‐reach places (for example sandy places or narrow openings), in which it is difficult to place or recover a catalyst.