Electrochemical method for synthesis of Cu2ZnSnS4 Nanorod/TiO2 nanotube arrays hybrid structure with enhanced photoelectrochemical properties

Cu2ZnSnS4 (CZTS) nanorod modified TiO2 nanotube arrays (TiO2-NTs) with enhanced visible-light activity were synthesized via a cathodic electrodeposition combined with sulfurization annealing route. The asformed Cu, Zn, Sn (CZT) mental precursors are highly dispersed inside the TiO2-NTs. The deposition of CZT onto the TiO2-NTs can be controlled by the deposition time. The proposed electrodeposition strategy results in the strong combination and heterojunctions between CZTS and TiO2 through generated electric field and capillary action. The morphology, crystal phases, and photoelectrochemical (PEC) properties of as-obtained CZTS/TiO2-NTs were investigated based on various characterizations. CZTS 30 s/TiO2-NTAs exhibits three-fold enhancement in their photocurrent under simulated sunlight illumination compared with pristine TiO2-NTs, indicating effective photogenerated electron transfer from CZTS to TiO2. The increased PEC activity is ascribed from strong combination and heterojunctions between CZTS and TiO2, favorable for visible-light response and fast charge separation of TiO2-NTs. In general, this suggested strategy can be useful in designing multi-junction semiconductor configuration such as coating nanostructures. (C) 2016 Elsevier B.V. All rights reserved.