Usage of natural leaf as a bio-template to inorganic leaf: Leaf structure black TiO2/CdS heterostructure for efficient photocatalytic hydrogen evolution

• Published in: International journal of hydrogen energy Vol. 46; no. 27; pp. 14369 - 14383
• Main Authors: Devaraji, Perumal, Gao, Ruchao, Xiong, Liuying, Jia, Xinjia, Huang, Li, Chen, Wei, Liu, Shanhu, Mao, Liqun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 19.04.2021
• Subjects: CdS; H2 generation; Hetero-junction; Leaf structure black TiO2; Photocatalyst; Hetero-junction; CdS; H2 generation; Photocatalyst; Leaf structure black TiO2
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2021.01.198

Herein, first time we report that highly efficient sheet like leaf structure black TiO2 (LBT)/CdS hetero-structure (LBT/CdS). Photocatalytic hydrogen generation was tested for different material in the presence of visible light (λ ≥ 420 nm) irradiation. 10 wt% of LBT loaded CdS (10LBT/CdS) exhibit maximum photocatalytic H2 generation rate about ~10 mmol h−1 g−1, which is higher than the H2 production results of pristine CdS (6 mmol h−1 g−1) and leaf black-TiO2 5.1 mmol h−1 g−1) respectively. Detailed characterization revealed that higher photocatalytic activity was mainly attributed to enormous spatial transfer efficiency of photo-excited charge carriers at the hetero-junction between LBT and CdS in LBT/CdS. Additionally, introduction of 2D black leaf-TiO2 to CdS act as a mat and enhances the mobility of charge carriers. In addition, presence of anatase-rutile surface-phase junction in leaf TiO2 (synthesized at 750 °C) and more edges, steps and corners on the CdS synergistically increased the photocatalytic H2 generation and photocurrent response of LBT/CdS. Bio template assisted (green leaf) co-catalyst free highly efficient LBT/CdS heterostructure for photocatalytic H2 generation under visible light irradiation. [Display omitted] •Leaf-black TiO2/CdS heterostructure synergistically enhance visible light absorption.•Introduction of natural leaf as a bio-template lead leaf network in the inorganic photocatalyst (TiO2).•The heterostructure between leaf-black TiO2 and CdS enhance the charge carrier transport and mitigate their recombination.•More edges and steps on CdS surface and 2D sheet like structure in the black TiO2 synergistically enhance the photocatalytic performance.