New Route To Synthesize Porous/Hollow Photocatalyst And Their Structure-activity Relationships Studies

This paper was committed to study preparation, characterization andphotocatalytic properties of porous/hollow photocatalysts. The mainresearch work is listed as the following parts:(1) Ternary Zn2SnO4octahedrons have been synthesized throughsolvothermal route, employing Na2SnO4, Zn(Ac)2, NaOH as reagent at160℃for18h. Furthermore, a facile approach have been used toconvert as-prepared ternary Zn2SnO4octahedrons to mesoporous binarySnO2hierarchical octahedrons assembled from nanorods through directselective complexing extraction of Zn2+ions in Zn2SnO4byethylenediaminetetraacetic acid (H4EDTA) for the first time. Zn2SnO4octahedrons can also convert into hollow SnS2hierarchical octahedronsassembled from nanosheets through additional introduction ofthioacetamide (TAA) as sulfur source into the chemical transformationsystem of Zn2SnO4to SnO2. The as-obtained products were characterizedby X-ray diffraction (XRD), Field-emission scanning electron microscope(FE-SEM), Transmission electron microscope (TEM), BET specificsurface area, energy dispersion X-ray (EDX), Inductively coupled plasma(ICP), UV-vis spectra, UV-vis diffuse reflectance spectroscopy,Fourier-transform infrared (FT-IR) spectra in detail. The formationmechanism of hierarchical SnO2and SnS2octahedrons was investigatedthrough series comparative experiments. The favorable structures of theas-obtained SnO2and SnS2leads to the observation of enhanced photocatalytic activities when evaluated as photocatalysts for degradationof organic pollutants.(2) Bi2(BDC)3nanoplates were synthesized through a mildsolution-phase self-assembly route, employing BDC (1,4-benzenedicarboxylate), ethanediol, NaOH and Bi(NO3)3as reagent. Thenthe macroporous BiVO4nanoplates were synthesized through directchemical conversion, using Bi2(BDC)3nanoplates as sacrificial templates.Subsequently, Fe2O3-modified macroporous BiVO4nanoplates wereobtained through a simple hydrothermal deposition-precipitation route.The as-obtained products were characterized by XRD, FE-SEM, TEM,EDX spectra, UV-vis, FT-IR spectra in detail. The photocatalytic resultsindicate that the as-obtained Fe2O3/BiVO4products displayed excellentphotocatalytic activities for degrading both dye and colorless organicpollutants. Based on a series of experimental results, Fe2O3as a role ofnon-precious metal co-catalyst in the present composite system wasproposed.