Materials Engineering, McGill University, Montreal, Canada, H3A 2B2.
Langmuir. 2010 Jun 15;26(12):9575-83. doi: 10.1021/la100137u.
Vibrational spectroscopic studies of N719 dye-adsorbed TiO(2) films have been carried out by using SERRS, ATR-FTIR, and confocal Raman imaging. The high wavenumber region (3000-4000 cm(-1)) of dye adsorbed TiO(2) is analyzed via Raman and IR spectroscopy to investigate the role of surface hydroxyl groups in the anchoring mode. As a complementary technique, confocal Raman imaging is employed to study the distribution features of key dye groups (COO-, bipyridine, and C=O) on the anatase surface. Sensitized TiO(2) films made from two different nanocrystalline anatase powders are investigated: a commercial one (Dyesol) and our synthetic variety produced through aqueous synthesis. It is proposed the binding of the N719 dye to TiO(2) to occur through two neighboring carboxylic acid/carboxylate groups via a combination of bidentate-bridging and H-bonding involving a donating group from the N719 (and/or Ti-OH) units and acceptor from the Ti-OH (and/or N719) groups. The Raman imaging distribution of COO(-)(sym) on TiO(2) was used to show the covalent bonding, while the distribution of C=O mode was applied to observe the electrostatically bonded groups.
采用表面增强共振拉曼散射（SERRS）、衰减全反射傅里叶变换红外光谱（ATR-FTIR）和共焦拉曼成像对 N719 染料吸附 TiO2 薄膜进行了振动光谱研究。通过拉曼和红外光谱分析染料吸附 TiO2 的高波数区域（3000-4000cm-1），研究表面羟基在固位模式中的作用。作为补充技术，共焦拉曼成像用于研究锐钛矿表面关键染料基团（COO-、联吡啶和 C=O）的分布特征。研究了两种不同纳米晶锐钛矿粉末制备的敏化 TiO2 薄膜：一种是商业的（Dyesol），另一种是通过水合成制备的我们的合成品种。提出 N719 染料与 TiO2 的结合通过两个相邻的羧酸/羧酸根基团通过双齿桥接和涉及 N719（和/或 Ti-OH）单元供体和 Ti-OH（和/或 N719）单元受体的 H 键合的组合发生。TiO2 上 COO-（sym）的 Raman 成像分布用于显示共价键合，而 C=O 模式的分布用于观察静电结合基团。
