Enhanced photocatalytic hydrogen production from water–methanol mixture using cerium and nonmetals (B/C/N/S) co-doped titanium dioxide

Abstract

In the present study, photocatalytic hydrogen production from water/methanol solution was investigated over cerium and nonmetal (B/C/N/S) co-doped titanium dioxide catalyst under visible light irradiation. The cerium and nonmetal co-doped titania photocatalysts were prepared by co-precipitation and characterized by surface area and pore size analysis, X-ray diffraction analysis, diffuse reflectance UV-Vis spectroscopy analysis, and photoluminescence analysis. The UV-Visible spectra showed that incorporation of cerium and nonmetals to TiO 2 resulted in narrow band gap and improved absorption of visible light. The band gap energy of co-doped samples depended on the properties of nonmetals. Photoluminescence studies showed that the radiative recombination rates of photogenerated electron-hole pairs were effectively suppressed by the addition of cerium and nonmetals and contributed to higher activity. The highest hydrogen production of 206 lmol/h was obtained for Ce-N-TiO 2 sample, which can be attributed to the higher surface area, higher absorption of visible light, and higher separation efficiency of electron-hole pairs in Ce-N-TiO 2 .

Highly crystalline anatase TiO2 nanocuboids as an efficient photocatalyst for hydrogen generation

“…15 However, the wide band gap of the anatase TiO 2 and the high recombination rate of photogenerated charge carriers have severely restricted the efficiency of TiO 2 . 16 Currently, several strategies such as metallic or nonmetallic ion doping 13,[16][17][18][19] noble metal deposition [20][21][22] and coupling with other semiconductors [23][24][25] are developed to extend its photoresponse to visible light or to improve the charge separation. Besides these methods, morphological modication is another adopted method.…”

A comparative study of 0D and 1D Ce-ZnO nanocatalysts in photocatalytic decomposition of organic pollutants

“…2,19,20 At this point, scientists are aware that ZnO NPs must be modied in order to increase photocatalytic activity. 21 The photocatalytic performance of semiconductor photocatalysts has been reported to be enhanced by doping specic atoms that serve as electron trapping agents to reduce electron-hole recombination rate. 2,20,22 This is due to the fact that dopants can serve as electron scavengers, preventing the recombination of electrons with holes.…”