污染物甲醛为电子给体Pt/TiO2光催化制氢

研究了甲醛为电子给体在Pt/TiO2上光催化生成氢的反应。甲醛经光催化降解产生CO2和甲酸，甲酸可进一步被氧化；甲醛的光催化降解与放氢同时发生，催化剂的最佳Pt负载量为0．5％，甲醛浓度对反应的影响，表观上符合Langmuir-Hinshelwood关系式；碱性条件有利于该反应；在甲醛浓度较低时，甲醇的存在能部分地提高放氢速率，并讨论了可能的反应机理。

Photocatalytic Hydrogen Generation by Pollutant Formaldehyde as Electron Donor over Pt/TiO2

Using formaldehyde as electron donor, the photocatalytic hydrogen evolution over Pt/TiO\-2 has been investigated. The photocatalytic oxidation of formaldehyde produced carbon dioxide and formic acid which can be oxidized thoroughly. The hydrogen evolution and the degradation of the pollutant formaldehyde can be carried out simultaneously in this reaction system. The photocatalyst was prepared by photodeposition. Optimal amount of Pt deposited on TiO\-2 was 0.5%. Effect of the concentration of formaldehyde on the reaction rate was consistant with the Langmuir\|Hinshelwood kinetic model. Alkaline condition favored this reaction. Containing methanol in formaldehyde solution with lower concentration, the rate of hydrogen evolution increased to some extent. A possible reaction mechanism was discussed.