2D/2D Heterojunction of TiO2 Nanoparticles and Ultrathin G-C3N4 Nanosheets for Efficient Photocatalytic Hydrogen Evolution

Ruifeng Du; Baoying Li; Xu Han; Ke Xiao; Xiang Wang; Chaoqi Zhang; Jordi Arbiol; Andreu Cabot

doi:10.3390/nano12091557

2D/2D Heterojunction of TiO₂ Nanoparticles and Ultrathin G-C₃N₄ Nanosheets for Efficient Photocatalytic Hydrogen Evolution

Nanomaterials (Basel). 2022 May 4;12(9):1557. doi: 10.3390/nano12091557.

Authors

Ruifeng Du^{1

2}, Baoying Li³, Xu Han⁴, Ke Xiao^{1

2}, Xiang Wang^{1

2}, Chaoqi Zhang^{1

2}, Jordi Arbiol^{4

5}, Andreu Cabot^{1

5}

Affiliations

¹ Catalonia Energy Research Institute-IREC, Sant Adrià de Besòs, 08930 Barcelona, Spain.
² Departament d'Enginyeria Electrònica i Biomèdica, Universitat de Barcelona, 08028 Barcelona, Spain.
³ Shandong Provincial Key Laboratory of Molecular Engineering, State Key Laboratory of Biobased Material and Green Papermaking, School of Chemistry and Chemical Engineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
⁴ Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
⁵ ICREA, Pg. Lluis Companys 23, 08010 Barcelona, Spain.

Abstract

Photocatalytic hydrogen evolution is considered one of the promising routes to solve the energy and environmental crises. However, developing efficient and low-cost photocatalysts remains an unsolved challenge. In this work, ultrathin 2D g-C₃N₄ nanosheets are coupled with flat TiO₂ nanoparticles as face-to-face 2D/2D heterojunction photocatalysts through a simple electrostatic self-assembly method. Compared with g-C₃N₄ and pure TiO₂ nanosheets, 2D/2D TiO₂/g-C₃N₄ heterojunctions exhibit effective charge separation and transport properties that translate into outstanding photocatalytic performances. With the optimized heterostructure composition, stable hydrogen evolution activities are threefold and fourfold higher than those of pure TiO_2, and g-C₃N₄ are consistently obtained. Benefiting from the favorable 2D/2D heterojunction structure, the TiO₂/g-C₃N₄ photocatalyst yields H₂ evolution rates up to 3875 μmol·g^-1·h^-1 with an AQE of 7.16% at 380 nm.

Keywords: 2D/2D heterojunction; charge separation; hydrogen evolution.

Grants and funding

R.D.: K.X., X.H., X.W. and C.Z. thank the China Scholarship Council for the scholarship support. IREC and ICN2 acknowledge funding from Generalitat de Catalunya, projects 2017 SGR 1246 and 2017 SGR 327, respectively. The authors thank the support from the project NANOGEN (PID2020-116093RB-C43), funded by MCIN/AEI/10.13039/501100011033/ and the project COMBENERGY (PID2019-105490RB-C32) from the Spanish Ministerio de Ciencia e Innovación. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and is funded by the CERCAProgramme / Generalitat de Catalunya. Baoying Li greatly appreciates the financial support from the National Natural Science Foundation of China (Nos. 22171154 & 21801144), the Youth Innovative Talents Recruitment and the Cultivation Program of Shandong Higher Education. This study was supported by MCIN with funding from the European Union NextGenerationEU (PRTR-C17.I1), Generalitat de Catalunya and by “ERDF A way of making Europe” by the “European Union”.