Study of photocatalytic hydrogen production and preparation on mesoporous metal(Niobium、Titanium) oxide

• Main Authors: Yi-Jain Hsieh, 謝毅堅
• Other Authors: Hsin-yu Lin
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/92668548980824524003

碩士 === 國立東華大學 === 材料科學與工程學系 === 98 === Hydrogen production by water splitting (2H2O catalyst/hv 2H2+O2) was examined over mesoporous niobium oxide and titanium oxide photocatalysts, prepared by evaporation-induced self-assembly (EISA) method. The typical mesoporous niobium oxide was synthesized by using NbCl5 as starting material and triblock copolymer P123 as template. The typical mesoporous titanium oxide was synthesized by using titanium isopropoxide (TTIP) as starting material and triblock copolymer P123 as template. To enhance the photocatalytic activity of these semiconductor photocatalys, a series of transition metal (M= Cr, W, Cu, and Ni) were doped to the mesoporous structure by one-pot synthesis process. The influences of the preparation parameters (including the metal loading, calcination condition) on the characteristics of the mesoporous niobium and oxide titanium oxide photocatalysts and their photocatalytic activities were investigated in detail. The catalysts were characterized by powder X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), N2 sorption and ultraviolet- visible spectroscopy (UV-vis), photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption isotherm. The photocatalytic water splitting are preformed in an aqueous MeOH, used as sacrificial hole scavengers under UV light irradiation. The rate of H2 evolution from an aqueous methanol solution under UV irradiation significantly changed with the variation of loading metal. Our results showed that the Cu doped mesoporous niobium and oxide titanium oxide photocatalysts exhibited the highest photoactivity. Cu doped mesoporous niobium oxides (Cu/Nb atomic ratio = 1/99) showed a rate of H2 production of 2060 μmol mol h-1 g-1 which was about 3.6 times than higher than mesoporous Nb2O5. Cu doped mesoporous titanium oxides (Cu/Ti atomic ratio = 1/99) showed a rate of H2 production of 10789 μmol mol h-1 g-1 which was about 9 times than higher than mesoporous TiO2.