Fabrication and Photoelectrochemical Performance Optimization of CuInS2 Quantum Dots Sensitized TiO2 Nanonails Array Photoelectrodes

Abstract

The CuInS2 quantum dots sensitization of TiO2 nanonails (NNs) array was successfully carried out by a successive ionic layer absorption and reaction (SILAR) method using CuCl2 ⋅ 2H2O, InCl3 ⋅ 4H2O and Na2S ⋅ 9H2O as precursors. The morphology, elemental composition and crystalline structure of the CuInS2 quantum dots sensitized TiO2 NNs array heterojunction nanostructures were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and X-ray-photoelectron spectroscopy (XPS). The above characterization results could unanimously reveal that the nanoparticles successfully loaded on the TiO2 NNs array can be assigned as CuInS2 quantum dots. UV-Vis absorption measurements indicated that the CuInS2 quantum dots sensitization extended the visible light absorption. The largest short-circuit photocurrent density of 17.7[Formula: see text]mA/cm2 was obtained, which indicated that the CuInS2 was a promising material in activating visible light functionalities and enhancing photoelectrochemical performance.