Facile synthesis of MnO2/TiO2 core-shell nanorods from aqueous solution and their photoelectrochemical behaviors

Highlights: • A facile synthetic method has been developed to prepare MnO₂/TiO₂ materials. • A core-shell microstructure was observed for the MnO₂/TiO₂ composite materials. • The as-prepared materials exhibit an effective photoelectrochemical activity. In this paper, a facile synthetic method combining the hydrothermal reaction with the liquid phase deposition (LPD) has been developed to prepare the MnO₂/TiO₂ composite materials from aqueous solution. The as-prepared materials were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM), respectively. It could be observed that the LPD-derived anatase TiO₂ nanocrystals were uniformly deposited on the α-MnO₂ nanorods, forming a core-shell microstructure. Additionally, the cyclic voltammetry was used to evaluate the photoelectrochemical behaviors of the as-prepared materials. The results revealed that the MnO₂/TiO₂ composite materials exhibited larger anodic photocurrent density than that of pure MnO₂ materials when the electrolyte solution (Na₂SO₄, 0.1 M) was saturated with CO₂ gas.