Issue 20, 2017

In situ nitrogen-doped hollow-TiO2/g-C3N4 composite photocatalysts with efficient charge separation boosting water reduction under visible light

Abstract

Visible-light-driven water splitting process is highly attractive for alternative energy utilization, while developing efficient, earth-abundant, and environmentally friendly photocatalysts for hydrogen evolution reaction has remained a major challenge. Herein, heterostructured photocatalysts composed of hollow N-doped TiO2 and g-C3N4 (N-TiO2/g-C3N4) were developed by an in situ impregnation calcination method. N-TiO2 and N-TiO2/g-C3N4 heterostructures with different ratios of N-TiO2 and g-C3N4 were synthesized by simply varying the amount of cyanamide (CY) as the g-C3N4 precursor. Using N-TiO2/g-C3N4 as a H2 evolution photocatalyst, the largest rate of 296.4 μmol g−1 h−1 was obtained under visible light irradiation (λ ≥ 420 nm) without any noble metal co-catalyst, which is 25.8 times larger than that of pure g-C3N4 (11.5 μmol g−1 h−1). Femtosecond time-resolved diffuse reflectance spectroscopy was used to evaluate the lifetime of photogenerated electrons and electron transfer dynamics in N-TiO2/g-C3N4. It is suggested that an additional decay pathway exists for the photogenerated electrons in N-TiO2/g-C3N4, in which N-TiO2 acts as an electron trapping site, leading to higher photocatalytic H2 evolution activity than pure g-C3N4. The present work not only provides a facile method for preparing doped materials and heterostructures with efficient photocatalytic activity, but also deepens the understanding of charge transfer dynamics in heterostructured photocatalysts.

Graphical abstract: In situ nitrogen-doped hollow-TiO2/g-C3N4 composite photocatalysts with efficient charge separation boosting water reduction under visible light

Supplementary files

Article information

Article type
Paper
Submitted
01 Mar 2017
Accepted
18 Apr 2017
First published
19 Apr 2017

J. Mater. Chem. A, 2017,5, 9671-9681

In situ nitrogen-doped hollow-TiO2/g-C3N4 composite photocatalysts with efficient charge separation boosting water reduction under visible light

X. Shi, M. Fujitsuka, Z. Lou, P. Zhang and T. Majima, J. Mater. Chem. A, 2017, 5, 9671 DOI: 10.1039/C7TA01888F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements