A CdS modified Sb–SnO 2/TiO 2-NTs hybrid electrode (CdS/Sb–SnO 2/TiO 2-NTs) with tailored architecture is studied for its photoelectrochemical applications. The visible light driven heterojunction photoelectrode was fabricated by anodic oxidation of titanium foil to obtain TiO 2 nanotube arrays firstly, and then solvothermally deposited with antimony doped tin oxide (Sb–SnO 2) thin coating onto the TiO 2 nanotube walls, followed by the successive ionic layer adsorption and reaction (SILAR) process to deposit certain amount of CdS nanoparticles. The obtained heterostructure was characterized by FE-SEM, EDS, XRD, XPS and UV–Vis techniques. The photoelectrochemical performance of this hybrid electrode demonstrated that the photocurrent under UV–Vis light illumination was remarkedly enhanced up to 17.48 mA/cm 2 under 1.0 V vs. Ag/AgCl. The enhanced photocurrent can be partially attributed to the narrow bandgap CdS nanoparticles, which allows for more visible light harvesting. On the other hand, the effect of Sb doping content on the photo-electrochemical activities of the composites was crucial. Thus a detailed investigation was carried out and the results showed that the nominal value of 2%(molar ratio) antimony loading exhibited the best photo-electrochemical performance. It is expected that the novel CdS/Sb–SnO 2/TiO 2 nanotube array hybrid system could serve as promising photoanode for effective hydrogen evolution from water splitting to meet the urgent problems of energy demand.
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