Influence of co-existing alcohol on charge transfer of H2 evolution under visible light with dye-sensitized nanocrystalline TiO2

The improvement of photocatalytic activity of TiO2-based nanomaterials is widely investigated due to the tentative of their industrialization as environmental photocatalysts and their inherently low solar spectrum sensitivity and rapid recombination of charge carriers. Coupling of oxygen-based bidentate diketone to nanocrystalline TiO2 represents a potential alternative for improving the holdbacks. Formation of TiO2-acetylacetone charge transfer complex (CTC) by sol-gel route results in a hybrid semiconductor material with photodegradation activity against toxic NOx gas. In this research, the influence of the chelating agent acetylacetone (ACAC) content on the CTC photocatalytic efficiency under visible light was evaluated. A high content of ACAC in the CTC is not a decisive factor for efficiency of photocatalytic reactions. In fact, the highest efficiency for NOx degradation (close to 100%, during 1 h of visible light exposure) was reported for the material calcined in air at 300 °C with the content of strongly bonded acetylacetone not higher than 3 wt.%. Higher calcination temperature (400 °C) left TiO2 almost completely depleted in ACAC, while at the highest applied temperature (550 °C) a portion of anatase was transformed into rutile and the sample is free of ACAC. The analyses pointed out that superoxide anion radical (O2−) plays an active role in photo-oxidation of NOx. Our findings indicate that this CTC has both high visible light spectral sensitivity and photocatalytic efficiency.

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Effect of Water/Acetonitrile Ratio on Dye-Sensitized Photocatalytic H2 Evolution under Visible Light Irradiation

Journal of Solar Energy Engineering ◽

10.1115/1.1878854 ◽

2004 ◽

Vol 127 (3) ◽

pp. 413-416 ◽

Cited By ~ 15

Author(s):

Ryu Abe ◽

Kazuhiro Sayama ◽

Hideki Sugihara

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Energy Gap ◽

Light Irradiation ◽

Acetonitrile Solution ◽

H2 Evolution ◽

Tio2 Photocatalysts ◽

Dye Sensitized ◽

Highest Occupied Molecular Orbital ◽

Splitting System

H 2 production in a water-acetonitrile solution containing iodide as an electron donor was investigated over dye-sensitized Pt∕TiO2 photocatalysts under visible light irradiation, as a potential water-splitting system based on an iodide redox mediator. The rates of H2 evolution decreased with increasing proportion of water in the solutions, because of a decrease in the energy gap between the redox potential of I3−∕I− and the highest occupied molecular orbital levels of the dyes, which decreases the efficiency of electron transfer from I− to dye.

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Influence of Ru(II) Bipyridyl Complex on the Photocatalytic H2 Evolution over TiO2 Nanoparticles with Mesostructures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.825 ◽

2008 ◽

Vol 47-50 ◽

pp. 825-828 ◽

Cited By ~ 1

Author(s):

Tian You Peng ◽

Ding Ning Ke ◽

Chun Wu ◽

Cai Ping ◽

Liang Ma ◽

...

Keyword(s):

Visible Light ◽

Dynamic Equilibrium ◽

H2 Production ◽

Electron Donors ◽

H2 Evolution ◽

Conjugation System ◽

Antenna Effect ◽

Dye Sensitized ◽

Sensitization Process ◽

Bipyridyl Complex

H2 production over dye-sensitized Pt/TiO2 nanoparticles with mesostructures under visible light was investigated by using methanol as electron donors. Three types of Ru(II) bipyridyl complexes, which can be attached to Pt/m-TiO2 with different linkage modes, show different photosensitization. The dye tightly linked with m-TiO2 has better durability but the lowest H2 evolution efficiency, whereas the loosely attached dyes possess higher H2 evolution efficiency and preferable durability. It seems that the dynamic equilibrium between the linkage of ground state dye with TiO2 and the divorce of oxidization state dye from the surfaces plays a crucial role in the photochemical behavior during photocatalyst sensitization process. The binuclear Ru(II) shows a better photosensitization in comparison with mono- nuclear Ru(II) dyes due to its large conjugation system and “antenna effect”, which, in turn, improve the visible light harvesting and electron transfer between the dye and TiO2.

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CdSe quantum dots modified thiol functionalized g-C3N4: Intimate interfacial charge transfer between 0D/2D nanostructure for visible light H2 evolution

Renewable Energy ◽

10.1016/j.renene.2020.05.140 ◽

2020 ◽

Vol 158 ◽

pp. 431-443 ◽

Cited By ~ 2

Author(s):

Shakeelur Raheman AR ◽

Higgins M. Wilson ◽

Bilal M. Momin ◽

Uday S. Annapure ◽

Neetu Jha

Keyword(s):

Quantum Dots ◽

Charge Transfer ◽

Visible Light ◽

Cdse Quantum Dots ◽

H2 Evolution ◽

Interfacial Charge Transfer ◽

Interfacial Charge

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An efficient visible-light-responsive surface charge transfer complex AA-TiO2 based dye-sensitized solar cell

Optik ◽

10.1016/j.ijleo.2020.164407 ◽

2020 ◽

Vol 207 ◽

pp. 164407 ◽

Cited By ~ 1

Author(s):

Tingxin Peng ◽

Jinlei Xu

Keyword(s):

Charge Transfer ◽

Solar Cell ◽

Visible Light ◽

Surface Charge ◽

Charge Transfer Complex ◽

Dye Sensitized Solar Cell ◽

Dye Sensitized

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Highly active dye-sensitized photocatalytic H2 evolution catalyzed by a single-atom Pt cocatalyst anchored onto g-C3N4 nanosheets under long-wavelength visible light irradiation

New Journal of Chemistry ◽

10.1039/c8nj02933d ◽

2018 ◽

Vol 42 (17) ◽

pp. 14083-14086 ◽

Cited By ~ 19

Author(s):

Yuan Xue ◽

Yonggang Lei ◽

Xiangyu Liu ◽

Yanan Li ◽

Wanan Deng ◽

...

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Light Irradiation ◽

Single Atom ◽

Eosin Y ◽

H2 Evolution ◽

Long Wavelength ◽

Dye Sensitized ◽

Highly Active ◽

Photocatalytic H2 Evolution

A single-atom Pt cocatalyst anchored onto g-C3N4 nanosheets could efficiently catalyze H2 evolution from an Eosin Y-sensitized system under 520 nm irradiation.

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