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

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 (lambda >= 420 nm) irradiation. 10 wt% of LBT loaded CdS (10LBT/CdS) exhibit maximum photocatalytic H-2 generation rate about similar to 10 mmol h(-1) g(-1), which is higher than the H-2 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 degrees C) and more edges, steps and corners on the CdS synergistically increased the photocatalytic H-2 generation and photo-current response of LBT/CdS. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study reports for the first time an efficient black TiO2/CdS hetero-structure with high photocatalytic hydrogen generation activity. The sheet like leaf structure of LBT/CdS exhibits a higher rate of H2 production, attributed to the hetero-junction between the two materials and the introduction of black leaf-TiO2 which enhances charge carrier mobility.