Preparation of SrTiO3 Cubes by Molten Salt Method and Its Surface Ions Modification with Cu(II) Clusters

doi:10.3724/SP.J.1077.2013.13048

Abstract

Abstract: Pure SrTiO₃ cubes with perovskite structure were prepared by a molten salt method. The novel visible light active photocatalysts were obtained as a result of surface modification of SrTiO₃ cubes with Cu ions by an impregnation technique. The as-prepared samples were characterized by an inductively coupled plasma atomic emission spectrometer, X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscope (XPS), and UV-Vis diffuse reflectance spectroscope (DRS). The decomposition of gaseous 2-propanol was chosen as a probe to evaluate the photocatalytic activities of the samples in air. The results show that the visible light photocatalytic activities of the samples can be significantly enhanced by grafting amorphous Cu(II) clusters on the surfaces of SrTiO₃. Under visible light irradiation, electrons in the valance band of SrTiO₃ are transferred to the surfaced Cu(II) clusters, leaving holes with strong oxidizing power in the valance band and producing Cu(I) clusters. The Cu(I) clusters can efficiently reduction oxygen molecules via a multi-electron reduction process to consume the excited electrons. On the other hand, the generated holes can decompose the organic compounds. As a result, the complete decomposition of gaseous 2-propanol into CO₂ can be achieved over the Cu(II)-SrTiO₃ under visible light irradiation.

Key words: SrTiO₃, photocatalysis, molten salt method, surface modification

CLC Number:

O643

LONG Zhen, WEI Xian-Hua, QIU Xiao-Qing. Preparation of SrTiO3 Cubes by Molten Salt Method and Its Surface Ions Modification with Cu(II) Clusters[J]. Journal of Inorganic Materials, 2013, 28(10): 1103-1107.

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