Abstract: A series of composite-crystal nano-TiO2 powder with various contents of rutile were synthesized by the sol-gel method，and were calcined at various temperatures. The effect of rutile content on photocatalytic water-splitting for hydrogen production over composite-crystal nano-TiO2 was studied in the presence of formaldehyde as sacrificial reagent. The results showed that TiO2 with pure anatase showed the best photocatalytic activity，and increase of rutile content caused a decrease of activity，during which a fluctuation was observed. As Pt was deposited on nano-TiO2 surface by the photo-reduction method，the rates of H2 evolution increased first and then decreased with the increase of rutile content. The maximum value，which reached 40.35 mmol/(gcat·h)，was obtained with nano-TiO2 containing 9.7% rutile. A mechanism of the effect of rutile content on photocatalytic water-splitting for hydrogen production over composite-crystal nano-TiO2 was proposed.

摘要： 合成了不同金红石相含量的纳米TiO2，并研究了其光催化分解水制氢的活性。结果表明，未沉积Pt时，纯锐钛矿TiO2活性最高，金红石相含量的增加导致TiO2活性下降并在下降过程中出现波动。沉积Pt后，TiO2产氢速率随金红石相含量的增加先增后减，在金红石相质量分数为9.7%时达到最高，为40.35 mmol/(gcat·h)。首次提出了金红石相含量对混晶纳米TiO2光催化分解水制氢活性的影响机理。