P-doped TiO2 Nanofibers Decorated with Ag Nanoparticles for Enhanced Photocatalytic Activity under Simulated Solar Light

Abstract

We report the synthesis of titania nanofibers (TNF) of ?195 nm mean diameter doped with phosphorus through one-pot electrospinning followed by decoration of Ag nanoparticles (NPs). The Ag NPs of ?8 nm size on 2 % P-doped TNFs (Ag-PTNFs) showed excellent photocatalytic activity for the reduction of Cr(VI), under simulated solar light, with ?100 % conversion to Cr(III) in 90 min at pH 3 with a pseudo-first order rate constant of 0.085 min?1 that is 96.5 % higher than TNFs. The Ag-PTNFs also exhibited excellent photodegradation of methylene blue with pseudo-first order rate constant of 0.052 min?1 which is 82.7 % better than TNFs. The enhanced photocatalytic performance of Ag-PTNFs is attributed to the reduced band-gap, increased charge separation and reduced recombination rates. A proposed photocatalytic mechanism based on the synergistic effect of both Ag and P doping is presented which highlights the potential of these composite materials for water remediation. © 2020 Wiley-VCH GmbH