Dye-sensitized photocatalysts with molecular dyes and widegap semiconductors have attracted attention because of their design flexibility, for example, tunable light absorption for visible-light water splitting. Although organic dyes are promising candidates as metal-free photosensitizers in dye-sensitized photocatalysts, their efficiency in H2 production has far been unsatisfactory compared to that of metal-complex photosensitizers, such as Ru(II) tris-diimine-type complexes. Here, we demonstrate the substantial improvement of carbazole–thiophene-based dyes used for dye-sensitized photocatalysts through systematic molecular design of the number of thiophene rings, substituents in the thiophene moiety, and the anchoring group. The optimized carbazole–thiophene dye-sensitized layered niobate exhibited a quantum efficiency of 0.3% at 460 nm for H2 evolution using a redox-reversible I− electron donor, which is six-times higher than that of the best coumarin-based metal-free dye reported to date. The dye-sensitized photocatalyst also facilitated overall water splitting when combined with a WO3-based O2-evolving photocatalyst and an I3−/I− redox shuttle mediator. The present metal-free dye provided a high dye-based turnover frequency for water splitting, comparable to that of the state-of-the-art Ru(II) tris-diimine-type photosensitizer, by simple adsorption onto a layered niobate. Thus, this study highlights the potential of metal-free organic dyes with appropriate molecular designs for the development of efficient water splitting.
Skip Nav Destination
,
,
,
,
,
,
,
Article navigation
28 January 2024
Research Article|
January 31 2024
Metal-free carbazole–thiophene photosensitizers designed for a dye-sensitized H2-evolving photocatalyst in Z-scheme water splitting Available to Purchase
Special Collection:
The Physical Chemistry of Solar Fuels Catalysis
Akinobu Nakada
;
Akinobu Nakada
(Data curation, Formal analysis, Investigation, Visualization, Writing – original draft)
1
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University
, Nishikyo-ku, Kyoto 615-8510, Japan
2
PRESTO, Japan Science and Technology Agency (JST)
, Kawaguchi, Saitama 332-0012, Japan
Search for other works by this author on:
Takayuki Yokota;
Takayuki Yokota
(Data curation, Formal analysis, Investigation)
1
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University
, Nishikyo-ku, Kyoto 615-8510, Japan
Search for other works by this author on:
Morihiko Ogura
;
Morihiko Ogura
(Data curation)
3
Catalysis Research Center and Graduate School of Life Science, Hokkaido University
, Kita-ku, Sapporo 001-0021, Japan
Search for other works by this author on:
Ninghui Chang
;
Ninghui Chang
(Data curation)
3
Catalysis Research Center and Graduate School of Life Science, Hokkaido University
, Kita-ku, Sapporo 001-0021, Japan
Search for other works by this author on:
Osamu Tomita;
Osamu Tomita
(Investigation, Writing – review & editing)
1
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University
, Nishikyo-ku, Kyoto 615-8510, Japan
Search for other works by this author on:
Akinori Saeki
;
Akinori Saeki
(Data curation, Writing – review & editing)
4
Department of Applied Chemistry, Graduate School of Engineering, Osaka University
, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
Search for other works by this author on:
Masamichi Ogasawara
;
Masamichi Ogasawara
(Data curation, Writing – review & editing)
5
Department of Natural Science, Graduate School of Science and Technology, Tokushima University
, Tokushima 770-8506, Japan
Search for other works by this author on:
Ryu Abe
Ryu Abe
a)
(Conceptualization, Funding acquisition, Project administration, Supervision, Writing – review & editing)
1
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University
, Nishikyo-ku, Kyoto 615-8510, Japan
a)Author to whom correspondence should be addressed: [email protected]
Search for other works by this author on:
Akinobu Nakada
1,2
Takayuki Yokota
1
Morihiko Ogura
3
Ninghui Chang
3
Osamu Tomita
1
Akinori Saeki
4
Masamichi Ogasawara
5
Ryu Abe
1,a)
1
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University
, Nishikyo-ku, Kyoto 615-8510, Japan
2
PRESTO, Japan Science and Technology Agency (JST)
, Kawaguchi, Saitama 332-0012, Japan
3
Catalysis Research Center and Graduate School of Life Science, Hokkaido University
, Kita-ku, Sapporo 001-0021, Japan
4
Department of Applied Chemistry, Graduate School of Engineering, Osaka University
, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
5
Department of Natural Science, Graduate School of Science and Technology, Tokushima University
, Tokushima 770-8506, Japan
a)Author to whom correspondence should be addressed: [email protected]
J. Chem. Phys. 160, 044710 (2024)
Article history
Received:
September 30 2023
Accepted:
January 09 2024
Citation
Akinobu Nakada, Takayuki Yokota, Morihiko Ogura, Ninghui Chang, Osamu Tomita, Akinori Saeki, Masamichi Ogasawara, Ryu Abe; Metal-free carbazole–thiophene photosensitizers designed for a dye-sensitized H2-evolving photocatalyst in Z-scheme water splitting. J. Chem. Phys. 28 January 2024; 160 (4): 044710. https://doi.org/10.1063/5.0179225
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
CREST—A program for the exploration of low-energy molecular chemical space
Philipp Pracht, Stefan Grimme, et al.
DeePMD-kit v2: A software package for deep potential models
Jinzhe Zeng, Duo Zhang, et al.
Related Content
Factors determining formation efficiencies of one-electron-reduced species of redox photosensitizers
J. Chem. Phys. (October 2020)
The physical chemistry of solar fuels catalysis
J. Chem. Phys. (September 2024)
Strategies for accessing photosensitizers with extreme redox potentials
Chem. Phys. Rev. (May 2022)
Exploring the light-induced dynamics in solvated metallogrid complexes with femtosecond pulses across the electromagnetic spectrum
J. Chem. Phys. (June 2020)
Perspective: Mechanistic investigations of photocatalytic processes with time-resolved optical spectroscopy
J. Chem. Phys. (October 2022)