Core-shell structure of reduced graphene oxide@Ag–TiO2 for photocatalytic H2O splitting and CH3OH dehydrogenation under UV light irradiation.

The H 2 production from water-splitting and dehydrogenation of waste alcohols is widely investigated in current years to find out greener, and more efficient photocatalyst materials. Reduced graphene oxide (rGO; 1-10 wt%) coated TiO 2 and Ag(1 wt%)-TiO 2 core-shell nanocomposites are fabricated for enhanced photocatalytic H 2 production from H 2 O-splitting and CH 3 OH-dehydrogenation under UV irradiation. These rGO@TiO 2 and rGO@Ag–TiO 2 catalysts are characterized by XRD, Raman, FE-SEM, HR-TEM, XPS, BET, CV, EDS-mapping, PL, and UV–vis DRS for morphological, structural, and optical properties. After rGO(1-3 wt%) coating over TiO 2 , the H 2 amount is increased from 5 to 14 mmol for H 2 O-splitting and 13–83 mmol via CH 3 OH-dehydrogenation during 5 h UV irradiation, respectively. Due to the synergetic effect of rGO and Ag, core-shell rGO(2-4 wt%) coated Ag–TiO 2 produced the highest amount of 108–133 mmol of H 2 from water-splitting and 440–450 mmol from CH 3 OH-dehydrogenation during 7 and 5 h UV irradiation, respectively. The work illustrates the potential of Ag-deposition and rGO-coating over TiO 2 for efficient H 2 production. This paper reports the high photocatalytic activity of core-shell rGO@Ag–TiO 2 nanostructure for improved H 2 production (∼14 mmol/h) via water splitting and (∼90 mmol/h) via dehydrogenation of methanol under 5 h UV light irradiation. [Display omitted] • Core-shell nanostructure of rGO@TiO 2 and rGO@Ag–TiO 2 are fabricated. • rGO coating and Ag deposition highly improved the photocatalytic activity of TiO 2. • rGO@Ag–TiO 2 displayed superior photoactivity than rGO@TiO 2 nanocatalyst. • Highest amount of H 2 gas is photogenerated by rGO@Ag–TiO 2 photocatalysts. • Efficient H 2 O splitting and CH 3 OH dehydrogenation by rGO@Ag–TiO 2 composite. [ABSTRACT FROM AUTHOR]