Photocatalyst Cd2Sb2O6.8 with High Photocatalytic Activity toward Benzene and Dyes

A nanocrystalline Cd 2 Sb 2 O 6.8 photocatalyst was synthesized from Cd(Ac) 2 and K 2 H 2 Sb 2 O 7 via a facile hydrothermal method for the first time. The obtained sample was characterized by X-ray diffraction, N 2 sorption−desorption, UV−vis diffuse reflectance spectroscopy, transmission electron microscopy, electron spin resonance, X-ray photoelectron spectroscopy, and Fourier transformation infrared spectroscopy. The photocatalytic activity of the sample was evaluated by the degradation of benzene in an O 2 gas stream and dyes in aqueous solution under ultraviolet (UV) light illumination. The results demonstrated that Cd 2 Sb 2 O 6.8 had exhibited a higher photocatalytic activity than that of P25 (Degussa Co.) in the degradation of benzene. For a longtime (40 h) reaction test, Cd 2 Sb 2 O 6.8 maintained a high activity, and no obvious deactivation was observed. In the liquid phase, degradation of methyl orange; salicylic acid; and Rhodamine B, Cd 2 Sb 2 O 6.8, also exhibited high photoactivity. A possible mechanism of the photocatalysis over Cd 2 Sb 2 O 6.8 is proposed.