Monolithic Ag-Mt dispersed Z-scheme pCN-TiO2 heterojunction for dynamic photocatalytic H2 evolution using liquid and gas phase photoreactors

Fabricating montmorillonite (Mt) dispersed Ag/pCN-TiO2 heterojunction for stimulating photocatalytic H-2 evolution using two/three phases photo-reactor systems has been investigated. Using Ag-Mt/pCN-TiO2 composite in three-phase, H-2 rate of 667 mu molh(-1) was obtained, much greater than TiO2-based samples due to superior charges separation with Ag SPR and Mt mediated effect. Among parameters, 0.15 g catalyst loading at pH 7 gives highest H-2 yield with glycerol sacrificial reagents. More interestingly, liquid system with glycerol gave best H-2 rate while gas-phase with methanol encouraged H-2 productivity. Furthermore, H-2 rate increased to 8230 mu molh(-1) using two-phase monolith reactor, 9.01 and 12.34 times greater than two-phase fixed-bed and three-phase slurry systems. Comparatively, highest AQY and SY of 39.85% and 54.86 mu molh(-1)cm(-3) were obtained using monolith. This superior efficiency was due to efficient photon-flux consumption, effective mass-transfer and large light-fluxed. These findings would be fruitful for further development for clean hydrogen production through photocatalytic water splitting. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.