Structure modulation of g-C3N4 in TiO2{001}/g-C3N4 hetero-structures for boosting photocatalytic hydrogen evolution. Issue 59 (18th November 2021)

• Record Type: Journal Article
• Authors: Shang, Qianqian; Fang, Yuzhen; Yin, Xingliang; Kong, Xiangjin
• Is Part Of: RSC advances. Volume 11:Issue 59(2021)
• Page Start: 37089
• Page End: 37102
• Publication Date: 2021-11-18
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d1ra07691d
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The structure of g-C3 N4 in the prepared TiO2 {001}/g-C3 N4 hetero-structures could be modulated from BCN to CN-NS, CN-NC or CN-QD by tuning the synthetic temperature. Abstract : Structure design of photocatalysts is highly desirable for taking full advantage of their abilities for H2 evolution. Herein, the highly-efficient TiO2 {001}/g-C3 N4 (TCN) heterostructures have been fabricated successfully via an in situ ethanol-thermal method. And the structure of g-C3 N4 in the TCN heterostructures could be exfoliated from bulk g-C3 N4 to nanosheets, nanocrystals and quantum dots with the increase of the synthetic temperature. Through detailed characterization, the structural evolution of g-C3 N4 could be attributed to the enhanced temperature of the ethanol-thermal treatment with the shear effects of HF acid. As expected, the optimal TCN-2 heterostructure shows excellent photocatalytic H2 evolution efficiency (1.78 mmol h −1 g −1 ) under visible-light irradiation. Except for the formed built-in electric field, the significantly enhanced photocatalytic activity of TCN-2 could be ascribed to the enhanced crystallinity of TiO2 {001} nanosheets and the formed g-C3 N4 nanocrystals with large surface area, which could extend the visible light absorption, and expedite the transfer of photo-generated charge carriers further. Our work could provide guidance on designing TCN heterostructures with the desired structure for highly-efficient photocatalytic water splitting.