High visible light-driven photocatalytic activity of large surface area Cu doped SnO2 nanorods synthesized by novel one-step microwave irradiation method

摘要

The paper investigates the structural, optical and photocatalytic activity of large surface area single crystalline copper (Cu) doped SnO2 nanorods (NRs) synthesized by a novel one-step microwave irradiation method. Powder X-ray diffraction (XRD) analysis confirms that both pure and Cu doped SnO2 are tetragonal rutile type structure (space group P42/mnm) formed during the microwave process within 10min without any post annealing treatment. Transmission electron microscopy (TEM) reveals that the as synthesized Cu doped SnO2 samples exhibited rod-like shape and the length was less than 80nm and diameter was about few nanometers. Typical selected-area electron diffraction (SAED) pattern indicates that, the growth direction of Cu-SnO2 nanorod is along [110] direction. The variety of phonon interaction in the pure and Cu doped SnO2 is observed by Raman spectroscopy. Electron paramagnetic resonance and X-ray photoelectron spectroscopy (XPS) confirms that the presence of copper and tin as Cu2+ and Sn4+ in state, respectively. The photocatalytic activity was monitored via the degradation of methylene blue (MB) and Rhodamine B (RhB) dyes and the Cu-SnO2 showed better photocatalytic activity than that of pure SnO2. This could be attributed to the effective electron-hole separation by surface modification.