TY - JOUR
T1 - Organic dye-sensitized TiO 2 as a versatile photocatalyst for solar hydrogen and environmental remediation
AU - Choi, Sung Kyu
AU - Yang, Hyun Sik
AU - Kim, Jae Hong
AU - Park, Hyunwoong
PY - 2012/6/13
Y1 - 2012/6/13
N2 - This study explores the applicability of organic dye-sensitized TiO 2 particles in the production of molecular hydrogen and remediation of environmental pollutants (4-chlorophenol and Cr(VI)) under visible light (λ>420nm). In order to examine the effect of number of anchoring groups, Ru-free organic dyes of donor-π-acceptor configuration are prepared with different numbers (n) of carboxylate anchoring groups (n=1, 2, and 3; referred to as D1, D2, and D3, respectively). All the three dyes are found to be effective at producing H 2 in the presence of electron donors (triethanolamine (TEOA) and ethylenediaminetetra-acetic acid (EDTA)) with the following orders: D3-D2>D1 (TEOA) and D3>D2-D1 (EDTA). FTIR studies reveal that D1 and D3 are anchored to the TiO 2 surface primarily via bidentate modes with a single carboxylate and two carboxylates, respectively. D2, in contrast, is anchored with one or two carboxylates, depending on the competing electron donors. The number of carboxylates is less important in the sensitized remediation of pollutants likely due to different photochemical conditions (oxic vs. anoxic) and various reaction pathways. A detailed systematic study is performed, including the UV-vis absorption characterization of free dyes and dye/TiO 2 samples, the photoelectrochemical behaviors of dye/TiO 2 electrodes, and the effects of dye concentrations, solution pH, and TiO 2 kind (Degussa P25 vs. Hombikat UV-100).
AB - This study explores the applicability of organic dye-sensitized TiO 2 particles in the production of molecular hydrogen and remediation of environmental pollutants (4-chlorophenol and Cr(VI)) under visible light (λ>420nm). In order to examine the effect of number of anchoring groups, Ru-free organic dyes of donor-π-acceptor configuration are prepared with different numbers (n) of carboxylate anchoring groups (n=1, 2, and 3; referred to as D1, D2, and D3, respectively). All the three dyes are found to be effective at producing H 2 in the presence of electron donors (triethanolamine (TEOA) and ethylenediaminetetra-acetic acid (EDTA)) with the following orders: D3-D2>D1 (TEOA) and D3>D2-D1 (EDTA). FTIR studies reveal that D1 and D3 are anchored to the TiO 2 surface primarily via bidentate modes with a single carboxylate and two carboxylates, respectively. D2, in contrast, is anchored with one or two carboxylates, depending on the competing electron donors. The number of carboxylates is less important in the sensitized remediation of pollutants likely due to different photochemical conditions (oxic vs. anoxic) and various reaction pathways. A detailed systematic study is performed, including the UV-vis absorption characterization of free dyes and dye/TiO 2 samples, the photoelectrochemical behaviors of dye/TiO 2 electrodes, and the effects of dye concentrations, solution pH, and TiO 2 kind (Degussa P25 vs. Hombikat UV-100).
KW - Artificial photosynthesis
KW - Cr reduction
KW - Dye structure
KW - Electron donors
KW - Water splitting
UR - http://www.scopus.com/inward/record.url?scp=84860295651&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2012.04.011
DO - 10.1016/j.apcatb.2012.04.011
M3 - Article
AN - SCOPUS:84860295651
SN - 0926-3373
VL - 121-122
SP - 206
EP - 213
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
ER -