Facet-Dependent Interfacial Charge Transfer in TiO2/Nitrogen-Doped Graphene Quantum Dots Heterojunctions for Visible-Light Driven Photocatalysis

Interfacial charge transfer is crucial in the efficient conversion of solar energy into fuels and electricity. In this paper, heterojunction composites were fabricated, comprised of anatase TiO2 with different percentages of exposed {101} and {001} facets and nitrogen-doped quantum dots (NGQDs) to enhance the transfer efficiency of photo-excited charge carriers. The photocatalytic performances of all samples were evaluated for RhB degradation under visible light irradiation, and the hybrid containing TiO2 with 56% {001} facets demonstrated the best photocatalytic activity. The excellent photoactivity of TiO2/NGQDs was owed to the synergistic effects of the following factors: (i) The unique chemical features of NGQDs endowed NGQDs with high electronic conductivities and provided its direct contact with the TiO2 surface via forming Ti–O–C chemical bonds. (ii) The co-exposed {101} and {001} facets were beneficial for the separation and transfer of charge carriers in anatase TiO2. (iii) The donor-acceptor interaction between NGQDs and electron-rich {101} facets of TiO2 could remarkably enhance the photocurrent, thus hindering the charge carriers recombination rate. Extensive characterization of their physiochemical properties further showed the synergistic effect of facet-manipulated electron-hole separation in TiO2 and donor-acceptor interaction in graphene quantum dots (GQDs)/TiO2 on photocatalytic activity.

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Amino-Functionalized Nitrogen-Doped Graphene Quantum Dots and Silver-Graphene Based Nanocomposites: Ultrafast Charge Transfer and a proof-of-concept study for bioimaging applications

Journal of Photochemistry and Photobiology A Chemistry ◽

10.1016/j.jphotochem.2021.113741 ◽

2021 ◽

pp. 113741

Author(s):

Ahmet Karatay ◽

Diğdem Erdener ◽

Cansu Gürcan ◽

Elif Akhuseyin Yildiz ◽

Açelya Yilmazer ◽

...

Keyword(s):

Quantum Dots ◽

Charge Transfer ◽

Graphene Quantum Dots ◽

Proof Of Concept ◽

Nitrogen Doped ◽

Concept Study ◽

Nitrogen Doped Graphene ◽

Doped Graphene ◽

Ultrafast Charge Transfer

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Self-assembled nitrogen-doped graphene quantum dots (N-GQDs) over graphene sheets for superb electro-photocatalytic activity

Applied Surface Science ◽

10.1016/j.apsusc.2019.02.228 ◽

2019 ◽

Vol 480 ◽

pp. 1035-1046 ◽

Cited By ~ 16

Author(s):

Rabia Riaz ◽

Mumtaz Ali ◽

Iftikhar Ali Sahito ◽

Alvira Ayoub Arbab ◽

T. Maiyalagan ◽

...

Keyword(s):

Quantum Dots ◽

Photocatalytic Activity ◽

Graphene Quantum Dots ◽

Graphene Sheets ◽

Nitrogen Doped ◽

Nitrogen Doped Graphene ◽

Doped Graphene ◽

Self Assembled

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Ultrathin BiOCl/nitrogen-doped graphene quantum dots composites with strong adsorption and effective photocatalytic activity for the degradation of antibiotic ciprofloxacin

Applied Surface Science ◽

10.1016/j.apsusc.2019.143655 ◽

2019 ◽

Vol 496 ◽

pp. 143655 ◽

Cited By ~ 15

Author(s):

Zhigang Mou ◽

Hui Zhang ◽

Zeman Liu ◽

Jianhua Sun ◽

Mingshan Zhu

Keyword(s):

Quantum Dots ◽

Photocatalytic Activity ◽

Graphene Quantum Dots ◽

Nitrogen Doped ◽

Strong Adsorption ◽

Nitrogen Doped Graphene ◽

Doped Graphene

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Enhanced photocurrent of a ZnO nanorod array sensitized with graphene quantum dots

RSC Advances ◽

10.1039/c5ra07836a ◽

2015 ◽

Vol 5 (73) ◽

pp. 59204-59207 ◽

Cited By ~ 22

Author(s):

Bingjun Yang ◽

Jiangtao Chen ◽

Linfan Cui ◽

Wenwen Liu

Keyword(s):

Quantum Dots ◽

Charge Transfer ◽

Graphene Quantum Dots ◽

Nanorod Array ◽

Zno Nanorod ◽

Interfacial Charge Transfer ◽

Zno Nanorod Array ◽

Interfacial Charge ◽

Sensitization Effect

GQDs have a remarkable sensitization effect on the photocurrent of ZNRA, which is due to the interfacial charge transfer.

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Construction of Plasmonic Ag and Nitrogen-Doped Graphene Quantum Dots Codecorated Ultrathin Graphitic Carbon Nitride Nanosheet Composites with Enhanced Photocatalytic Activity: Full-Spectrum Response Ability and Mechanism Insight

ACS Applied Materials & Interfaces ◽

10.1021/acsami.7b14541 ◽

2017 ◽

Vol 9 (49) ◽

pp. 42816-42828 ◽

Cited By ~ 82

Author(s):

Yaocheng Deng ◽

Lin Tang ◽

Chengyang Feng ◽

Guangming Zeng ◽

Jiajia Wang ◽

...

Keyword(s):

Quantum Dots ◽

Photocatalytic Activity ◽

Carbon Nitride ◽

Graphene Quantum Dots ◽

Graphitic Carbon Nitride ◽

Full Spectrum ◽

Nitrogen Doped ◽

Nitrogen Doped Graphene ◽

Doped Graphene ◽

Spectrum Response

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Donor–Acceptor Interaction Determines the Mechanism of Photoinduced Electron Injection from Graphene Quantum Dots into TiO2: π-Stacking Supersedes Covalent Bonding

Journal of the American Chemical Society ◽

10.1021/jacs.6b09598 ◽

2017 ◽

Vol 139 (7) ◽

pp. 2619-2629 ◽

Cited By ~ 58

Author(s):

Run Long ◽

David Casanova ◽

Wei-Hai Fang ◽

Oleg V. Prezhdo

Keyword(s):

Quantum Dots ◽

Graphene Quantum Dots ◽

Electron Injection ◽

Covalent Bonding ◽

Acceptor Interaction ◽

Π Stacking ◽

Donor Acceptor

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Inter-molecular Electronic Transfer

MRS Proceedings ◽

10.1557/proc-1207-n09-05 ◽

2009 ◽

Vol 1207 ◽

Author(s):

Karel Král ◽

Miroslav Menšík

Keyword(s):

Quantum Dots ◽

Charge Transfer ◽

Carrier Transport ◽

Transport Theory ◽

Charge Carriers ◽

Optical Phonons ◽

Tunneling Mechanism ◽

Molecular Transfer ◽

Donor Acceptor

AbstractThe transport of electric charge is an important phenomenon in the systems like interacting quantum dots and molecules, and in polymers, including DNA molecules. We expect that in these nanostructure systems the key role is played by the interaction of the charge carriers with the optical phonons. We show the role of the multiple scattering of the charge carriers on the optical phonons in the inter-molecular transfer. The charge carrier transport based on this mechanism will be discussed theoretically and compared with the earlier experimental results on the charge transport in molecular Donor-Acceptor charge transfer crystals and also in other systems. In order to treat theoretically the electron transfer between two zero-dimensional nanostructures, we will use the model of two interacting quantum dots coupled by the electron inter-dot tunneling mechanism. A connection with the popular Marcus semiclassical charge transfer theory between molecules is also shown. We will use the nonequilibrium quantum electronic transport theory based on the nonequilibrium Green's functions.

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