State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian 116023, Liaoning, PR China.
J Am Chem Soc. 2013 Jul 17;135(28):10206-9. doi: 10.1021/ja4030963. Epub 2013 Jul 5.
It is well established that adding methanol to water could significantly enhance H2 production by TiO2. Recently, we have found that methanol can be photocatalytically dissociated on TiO2(110) at 400 nm via a stepwise mechanism. However, how molecular hydrogen can be formed from the photocatalyzed methanol/TiO2(110) surface is still not clear. In this work, we have investigated deuterium formation from photocatalysis of the fully deuterated methanol (CD3OD) on TiO2(110) at 400 nm using a temperature programmed desorption (TPD) technique. Photocatalytic dissociation products formaldehyde (CD2O) and D-atoms on BBO sites (via D2O TPD product) have been detected. In addition to D2O formation by heating the photocatalyzed methanol/TiO2(110) surface, we have also observed D2 product formation. D2 is clearly formed via thermal recombination of the D-atoms on the BBO sites from photocatalysis of methanol. Experimental results indicate that D2O formation is more important than D2 formation and that D2 formation is clearly affected by the D2O formation process.
甲醇添加到水中可以显著提高 TiO2 的氢气生成量，这一事实已得到充分证实。最近，我们发现甲醇可以在 400nm 下通过逐步机制在 TiO2(110)上光催化分解。然而，从光催化甲醇/TiO2(110)表面如何形成分子氢仍不清楚。在这项工作中，我们使用程序升温脱附（TPD）技术研究了在 400nm 下用全氘化甲醇（CD3OD）进行光催化时在 TiO2(110)上形成氘的情况。已经检测到光催化解离产物甲醛（CD2O）和 BBO 位上的 D 原子（通过 D2O TPD 产物）。除了通过加热光催化甲醇/TiO2(110)表面来形成 D2O 之外，我们还观察到了 D2 产物的形成。D2 显然是通过甲醇光催化中 BBO 位上 D 原子的热复合形成的。实验结果表明，D2O 的形成比 D2 的形成更为重要，并且 D2 的形成明显受到 D2O 形成过程的影响。
