BN/Cs2CO3/TiO2 composite nanofibers to improve hydrogen generation

This study describes the synthesis of cesium carbonate-titanium dioxide (Cs2CO3/TiO2) and boron nitride-cesium carbonate-titanium dioxide (BN/Cs2CO3/TiO2) nanofiber photocatalysts by electrospinning. The nanofiber properties were modulated by varying Cs2CO3 mole percentage. In all prepared nanofibers, the anatase TiO2 structure was the main phase. Cs2CO3 addition in the electrospinning mixture led to the formation of small amounts of rutile phase and decreased the anatase phase crystallinity. The highest photocatalytic activity was observed with the Cs2CO3/TiO2 photocatalyst that included 1.5 mol% of Cs2CO3. Indeed, the hydrogen production rate (9853 mu mol center dot g-1 center dot after 6 h under visible light) was 89.6 times higher than with pure TiO2 nanofibers. Modification of the 1.5% Cs2CO3/TiO2 photocatalyst with hexagonal BN further increased hydrogen production up to 15823 mu mol/g (6 h under visible light). This improvement could be explained by the presence of BN sheets in the BN/Cs2CO3/TiO2 catalyst that improve the separation of the photoinduced electron-hole pairs in TiO2 and increase the specific surface area compared with pure TiO2 and Cs2CO3/TiO2 nanofibers.(c) 2023 Elsevier B.V. All rights reserved.