Wiley, Journal of Chemical Technology and Biotechnology, p. n/a-n/a
DOI: 10.1002/jctb.4979
Full text: Unavailable
BACKGROUND: Hydrogen, as a clean and renewable energy source has become very attractive due to the deterioration of the global environment. In this way photocatalytic water-splitting for H2 production using light energy in the presence of semiconductors capable of absorbing such irradiation has become a promising approach for generation of H2. The intensity of incident solar energy on the earth's surface is 1000Wm-2 and only 4% of the total solar energy corresponds to UV light (40Wm-2), but this could be sufficient for H2 production from water splitting with very efficient semiconductors using the UV solar energy radiation. RESULTS: The synthesis of Bi2S3-TiO2 composites using TiO2 sol-gel (3, 6 and 9 Bi2S3 wt%) was performed by a solvothermal method and these materials were evaluated under UV light irradiation (254nm, 2W) for photocatalytic hydrogen production from a water/methanol solution. The optimal loading was obtained for the Bi2S3-TiO2 composite at 6wt% showing a production of 2460μmolh-1 g-1 of hydrogen, increasing by a factor of 4 the production of bare TiO2 at 564μmolh-1 g-1. The Bi2S3-TiO2 composite presented good stability after three complete cycles of reaction, proving resistance to corrosion effects. CONCLUSION: Bi2S3-TiO2 presented a higher photocatalytic activity than bare TiO2 for an optimal content of 6wt% Bi2S3-TiO2 .This improvement is attributed to enhanced absorption in the UV-Vis region of the Bi2S3-TiO2 composite, and a higher transference of the charge carriers in the Bi2S3-TiO2 heterojunctions with a hindered recombination e-/h+.