Hierarchical assembly of ultrathin hexagonal SnS2 nanosheets onto electrospun TiO2 nanofibers: enhanced photocatalytic activity based on photoinduced interfacial charge transfer

作者：Zhang, Zhenyi; Shao, Changlu^*; Li, Xinghua; Sun, Yangyang; Zhang, Mingyi; Mu, Jingbo; Zhang, Peng; Guo, Zengcai; Liu, Yichun

来源：Nanoscale, 2013, 5(2): 606-618.

DOI：10.1039/c2nr32301j

• VISIBLE-LIGHT
• HYDROTHERMAL SYNTHESIS
• HIGH-PERFORMANCE
• OPTICAL-PROPERTIES
• H-2 EVOLUTION
• THIN-FILMS
• SOLVOTHERMAL SYNTHESIS
• SILVER NANOPARTICLES
• AQUEOUS CR(VI)
• SOLAR-CELLS

Well-designed hierarchical nanostructures with one dimensional (1D) TiO2 nanofibers (120-350 nm in diameter and several micrometers in length) and ultrathin hexagonal SnS2 nanosheets (40-70 nm in lateral size and 4-8 nm in thickness) were successfully synthesized by combining the electrospinning technique (for TiO2 nanofibers) and a hydrothermal growth method (for SnS2 nanosheets). The single-crystalline SnS2 nanosheets with a 2D layered structure were uniformly grown onto the electrospun TiO2 nanofibers consisted of either anatase (A) phase or anatase-rutile (AR) mixed phase TiO2 nanoparticles. The definite heterojunction interface between SnS2 nanosheets and TiO2 (A or R) nanoparticles were investigated by high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). Moreover, the as-prepared SnS2/TiO2 hierarchical nanostructures as nanoheterojunction photocatalysts exhibited excellent UV and visible light photocatalytic activities for the degradation of organic dyes (rhodamine B and methyl orange) and phenols (4-nitrophenol), remarkably superior to the TiO2 nanofibers and the SnS2 nanosheets, mainly owing to the photoinduced interfacial charge transfer based on the photosynergistic effect of the SnS2/TiO2 heterojunction. Significantly, the SnS2/TiO2 (AR) hierarchical nanostructures as the tricomponent heterojunction system possessed stronger photocatalytic activity than the bicomponent heterojunction system of SnS2/TiO2 (A) hierarchical nanostructures or TiO2 (AR) nanofibers, which was discussed in terms of the three-way photosynergistic effect between SnS2, TiO2 (A) and TiO2 (R) component in the SnS2/TiO2 (AR) heterojunction resulting in the high separation efficiency of photoinduced electron-hole pairs, as evidenced by photoluminescence (PL) and surface photovoltage spectra (SPS).

• 出版日期2013
• 单位东北师范大学