TY - JOUR
T1 - Probing the charge separation process on In2S3/Pt-TiO2 nanocomposites for boosted visible-light photocatalytic hydrogen production
AU - Wang, Fenglong
AU - Jin, Zuanming
AU - Jiang, Yijiao
AU - Backus, Ellen H. G.
AU - Bonn, Mischa
AU - Lou, Shi Nee
AU - Turchinovich, Dmitry
AU - Amal, Rose
PY - 2016/12/5
Y1 - 2016/12/5
N2 - A simple refluxing wet-chemical approach is employed for fabricating In2S3/Pt-TiO2 heterogeneous catalysts for hydrogen generation under visible light irradiation. When the mass ratio between Pt-TiO2 and cubic-phased In2S3 (denoted as In2S3/Pt-TiO2) is two, the composite catalyst shows the highest hydrogen production, which exhibits an 82-fold enhancement over in-situ deposited Pt-In2S3. UV-vis diffuse reflectance and valence band X-ray photoelectron spectra elucidate that the conduction band of In2S3 is 0.3 eV more negative compared to that of TiO2, favouring charge separation in the nanocomposites. Photoelectrochemical transient photo-current measurements and optical pump - terahertz probe spectroscopic studies further corroborate the charge separation in In2S3/Pt-TiO2. The migration of photo induced electrons from the In2S3 conduction band to the TiO2 conduction band and subsequently into the Pt nanoparticles is found to occur within 5 ps. Based on the experimental evidence, a charge separation process is proposed which accounts for the enhanced activity exhibited by the In2S3/Pt-TiO2 composite catalysts.
AB - A simple refluxing wet-chemical approach is employed for fabricating In2S3/Pt-TiO2 heterogeneous catalysts for hydrogen generation under visible light irradiation. When the mass ratio between Pt-TiO2 and cubic-phased In2S3 (denoted as In2S3/Pt-TiO2) is two, the composite catalyst shows the highest hydrogen production, which exhibits an 82-fold enhancement over in-situ deposited Pt-In2S3. UV-vis diffuse reflectance and valence band X-ray photoelectron spectra elucidate that the conduction band of In2S3 is 0.3 eV more negative compared to that of TiO2, favouring charge separation in the nanocomposites. Photoelectrochemical transient photo-current measurements and optical pump - terahertz probe spectroscopic studies further corroborate the charge separation in In2S3/Pt-TiO2. The migration of photo induced electrons from the In2S3 conduction band to the TiO2 conduction band and subsequently into the Pt nanoparticles is found to occur within 5 ps. Based on the experimental evidence, a charge separation process is proposed which accounts for the enhanced activity exhibited by the In2S3/Pt-TiO2 composite catalysts.
KW - Hydrogen generation
KW - In2S3/Pt-TiO2
KW - Visible-light photocatalysis
KW - Charge transfer and separation
KW - Optical pump-terahertz probe spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=84995942125&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2016.05.048
DO - 10.1016/j.apcatb.2016.05.048
M3 - Article
SN - 0926-3373
VL - 198
SP - 25
EP - 31
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
ER -