Efficient visible light-induced photoelectrocatalytic hydrogen production using CdS sensitized TiO₂ nanorods on TiO₂ nanotube arrays

Abstract

A novel CdS/TiO 2 nanorods/TiO 2 nanotube array (CdS/TNRs/TNT) photocatalyst was prepared. The selforganized highly oriented TiO 2 nanotube arrays (TNTs) were first synthesized by anodizing Ti sheets. The "flower-like" rutile TiO 2 nanorods (TNRs) were then grafted on the TNTs by a hydrothermal method.Subsequently, the CdS quantum dots (CdS QDs) were deposited on the surface of the resulting TNRs/ TNTs using a sequential-chemical bath deposition (S-CBD) method. UV-vis diffuse reflectance spectra indicated that the CdS/TNRs/TNTs sample showed significantly enhanced absorption in the range from 350 to 700 nm. The photoelectrocatalytic hydrogen production activities of all samples were evaluated by using Na 2 S and Na 2 SO 3 as sacrificial reagents in water under a 300 W Xe lamp with a UV-light filter (l > 420 nm). The results showed that CdS/TNRs/TNTs prepared by hydrothermal reactions for 4 h and S-CBD 15 cycles showed a hydrogen production rate approximately 14 times that of the TNTs. When compared to CdS/TNTs, CdS/TNRs/TNTs showed a 2.3 fold increase in hydrogen production, which can be attributed to the enlarged effective deposition area for CdS QDs by depositing "flower-like" rutile TiO 2 nanorods on the TNTs. In addition, CdS/TNRs/TNTs exhibited excellent hydrogen production stability using Na 2 S and Na 2 SO 3 as sacrificial reagents.

12.29% Low Temperature–Processed Dopant‐Free CdS/p‐Si Heterojunction Solar Cells

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One‐dimensional TiO2 Nanotube Photocatalysts for Solar Water Splitting

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In situ synthesis of Bi2S3 sensitized WO3 nanoplate arrays with less interfacial defects and enhanced photoelectrochemical performance

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