Morphologic control of Sb-rich Sb2Se3 to adjust its catalytic hydrogenation properties for p-nitrophenol

Abstract

Sb-rich Sb₂Se₃ with hollow spherical morphologies and Se-rich Sb₂Se₃ with rod-like shapes were prepared by a hydrothermal method using sodium borohydride as the reductant. It was found that the material with high Sb content and microsphere-like morphology exhibits efficient catalytic performance for the hydrogenation of p-nitrophenol. A systematic study on the effect of hydrothermal reaction time on the structure and morphology of Sb-rich Sb₂Se₃ showed that the products are mainly composed of rod-like and hollow sphere-like Sb₂Se₃ under the different conditions; the microspherical particles are mainly composed of Sb and Sb₂Se₃, while the rod-like particles are made of Se-rich Sb₂Se₃. The longer hydrothermal reaction duration with an Sb/Se atomic ratio of 1 : 1.2 increased the amount of spherical Sb-rich Sb₂Se₃ particles, which showed enhanced catalytic activities. The hollow spherical Sb-rich Sb₂Se₃ particles were found to exhibit much better catalytic performances than the rod-shaped Se-rich Sb₂Se₃, which may be attributed to the higher dispersity of antimony and the small sizes of the hollow spherical Sb-rich Sb₂Se₃ particles (less than 50 nm). The potential growth mechanisms for the different morphologies of Sb-rich Sb₂Se₃ have been proposed by analysing the samples at different growth stages.