Bhachu Davinder S, Sathasivam Sanjayan, Carmalt Claire J, Parkin Ivan P
Materials Chemistry Centre, Department of Chemistry, University College London , 20 Gordon Street, London WC1H 0AJ, U.K.
Langmuir. 2014 Jan 21;30(2):624-30. doi: 10.1021/la4038777. Epub 2014 Jan 6.
PbO clusters were deposited onto polycrystalline titanium dioxide (anatase) films on glass substrates by aerosol-assisted chemical vapor deposition (AACVD). The as-deposited PbO/TiO2 films were then tested for visible light photocatalysis. This was monitored by the photodegradation of stearic acid under visible light conditions. PbO/TiO2 composite films were able to degrade stearic acid at a rate of 2.28 × 10(15) molecules cm(-2) h(-1), which is 2 orders of magnitude greater than what has previously been reported. The PbO/TiO2 composite film demonstrated UVA degradation of resazurin redox dye, with the formal quantum yield (FQY) and formal quantum efficiency (FQE) exceeding that of a TiO2 film grown under the same conditions and Pilkington Activ, a commercially available self-cleaning glass. This work correlates with computational studies that predicted PbO nanoclusters on TiO2 form active visible light photocatalysts through new electronic states through PbO/TiO2 interfacial bonds resulting in new electronic states above the valence band maximum in TiO2, shifting the valence band upward as well as more efficient electron/hole separation with hole localization on PbO particles and electron on the TiO2 surface.
通过气溶胶辅助化学气相沉积（AACVD）将PbO团簇沉积在玻璃基板上的多晶二氧化钛（锐钛矿）薄膜上。然后对沉积后的PbO/TiO₂薄膜进行可见光光催化测试。这通过在可见光条件下硬脂酸的光降解来监测。PbO/TiO₂复合薄膜能够以2.28×10¹⁵分子·cm⁻²·h⁻¹的速率降解硬脂酸，这比之前报道的速率高2个数量级。PbO/TiO₂复合薄膜展示了刃天青氧化还原染料的UVA降解，其形式量子产率（FQY）和形式量子效率（FQE）超过了在相同条件下生长的TiO₂薄膜以及市售自清洁玻璃Pilkington Activ。这项工作与计算研究相关，该研究预测TiO₂上的PbO纳米团簇通过PbO/TiO₂界面键形成新的电子态，从而形成活性可见光光催化剂，导致在TiO₂价带最大值之上产生新的电子态，使价带向上移动，同时实现更有效的电子/空穴分离，空穴定位于PbO颗粒上，电子位于TiO₂表面。
