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

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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Photosensitization of Ruthenium(II) Complex on Titania for Photocatalytic H2 Evolution Under Visible-Light Irradiation

Volume 12: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2008-69172 ◽

2008 ◽

Author(s):

Tianyou Peng ◽

Ke Dai ◽

Huabing Yi ◽

Dingning Ke ◽

Ping Cai

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Dynamic Equilibrium ◽

Irradiation Time ◽

Light Irradiation ◽

H2 Evolution ◽

Conjugation System ◽

Antenna Effect ◽

Dye Sensitized ◽

Photocatalytic H2 Evolution

Hydrogen production over dye-sensitized Pt/P25 under visible-light irradiation was investigated by using methanol or TEOA as an electron donor. The binuclear Ru(II) dye (Ru2(bpy)4L1-PF6) shows the best photosensitization in both sacrificial reagent solutions due to its larger conjugation system and “antenna effect”, which is loosely linked with TiO2 and exhibits more steady and higher increases in H2 evolution upon prolonging the irradiation time in comparison with the tightly linked N719. The dynamic equilibrium between the linkage of ground dye and divorce of oxidized dye from TiO2 can enhance the electron injection and hinder the backward transfer, and then improve the H2 evolution efficiency.

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Enhancing H2 evolution and molecular oxygen activation via dye sensitized BiOBr0.9I0.1 under visible light

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2020.07.014 ◽

2020 ◽

Vol 580 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Liping Han ◽

Yuewei Lv ◽

Bo Li ◽

Hao Wen ◽

Hongwei Huang ◽

...

Keyword(s):

Visible Light ◽

Molecular Oxygen ◽

Oxygen Activation ◽

H2 Evolution ◽

Dye Sensitized

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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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Dye-Sensitized Photocatalyst System for Water Splitting Into H2 and O2 Under Visible Light Irradiation

Solar Energy ◽

10.1115/isec2004-65070 ◽

2004 ◽

Author(s):

Ryu Abe ◽

Kazuhiro Sayama ◽

Hironori Arakawa

Keyword(s):

Visible Light ◽

Water Splitting ◽

Visible Light Irradiation ◽

Energy Gap ◽

H2 Production ◽

Light Irradiation ◽

Mixed Solution ◽

Tio2 Photocatalysts ◽

Dye Sensitized ◽

Splitting System

H2 production from a water-acetonitrile mixed solution containing iodide electron donor was investigated over dye-sensitized Pt/TiO2 photocatalysts under visible light irradiation, as a part of water splitting system using iodide redox mediator. The rates of H2 evolution were decreased with the increase of the water ratio in the mixed solutions, because of the decrease in energy gap between the redox potential of I3−/I− and the HOMO levels of the dyes, which lowing the efficiency of electron transfer from I− to dye.

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Construction of K+ ions gradient in crystalline carbon nitride to accelerate charge separation for efficient visible light H2 production

10.21203/rs.3.rs-145087/v1 ◽

2021 ◽

Author(s):

Guoqiang Zhang ◽

Yangsen Xu ◽

Chuan-Xin He ◽

Yongliang Li ◽

Xiangzhong Ren ◽

...

Keyword(s):

Visible Light ◽

Driving Force ◽

Carbon Nitride ◽

Photocatalytic Performance ◽

H2 Production ◽

H2 Evolution ◽

Concentration Gradients ◽

Diffusion Controlled ◽

Activity Enhancement ◽

First Time

Abstract Like most of the recent reported semiconductor photocatalysts, the sluggish dynamic charges transfer and separation caused by weak driving force still restricts the further improvement of photocatalytic performance in crystalline carbon nitride (CCN). Here, we successfully prepared a series of heptazine-based K+ implanted CCN (KCN) for the first time, where the K+ ions concentration was gradiently inserted through controlling its diffusion from the surface to bulk in carbon nitride (CN). As a powerful driving force, the built-in electric field (BIEF) induced by this concentration gradient, greatly accelerates the drift movement and the transport from bulk to the surface, as well as the separation of photogenerated carriers. Consequently, the KCN with optimized BIEF displays a ～34 times promotion than original CN for visible-light H2 evolution. Such a high activity enhancement factor is at a relatively good level in reported CCN. Our proposed strategy to induce BIEF production by constructing concentration gradients through thermodynamically feasible diffusion controlled solid-state reaction, can be adopted to build other efficient photocatalytic systems.

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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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