Abstract
Barium cerate BaCeO3, with the perovskite-like and 4f electronic structure of its conduction band, is a material that found applications in photocatalytic hydrogen production from water splitting and solid oxide fuel cells. In fine-tuning of the material, one needs to overcome the hurdle of fast recombination of photogenerated electron-hole pairs. This usually is achieved via metal and other atoms doping. In this paper, we report our attempts to increase the efficiency of the water-splitting reaction when using BaCeO3 by doping it with V, Ag, Au, and Pt. Pure BaCeO3 nanoneedles were synthesized employing a sol-gel method. The nanoneedles were then doped with the afore-mentioned elements. Characterization of the material was carried out via XRD, UV-Vis, TEM, PL, photocurrent intensity, and N-2-adsorption measurements. Photocatalytic water splitting was set up under conditions that simulate the natural sunlight with the utilization of glycerol as a scavenger. While pure BaCeO3 does not show appreciable activity towards water splitting, Pt-BaCeO3 produced the best results compared with the other three elements used as dopants. The rate of H-2 production using BaCeO3, V-BaCeO3, Ag-BaCeO3, Au-BaCeO3, and Pt-BaCeO3 was 28, 500, 900, 1800, and 2400molg(-1), respectively. The superior performance of Pt-doped and Au-doped BaCeO3 can be explained by the narrow bandgap (Pt: 2.16eV, Au: 2.36eV), high surface area (Pt: 36.0m(2)/g, Au: 38.0m(2)/g), and the compatible 4f electronic structure of BaCeO3 and Pt and Au.
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HighlightsBaCeO(3) nanoneedles and V, Ag, Au, and Pt-doped BaCeO3 nanoneedles have been prepared via sol-gel process.Heterogeneous the photocatalytic process was employed for hydrogen production.Pt-doped and Au-doped BaCeO3 nanoneedles have superior performance for hydrogen production.Rate of hydrogen evolved of Pt-doped BaCeO3 nanoneedles are higher than 85.7 for BaCeO3 nanoneedles.Reusability test demonstrated the photostability of Pt-doped BaCeO3 nanoneedles after five cycles.