TiO_(2)几何和电子结构调制用于超灵敏SERS传感

Geometric and Electronic Structure Modulation of TiO_(2)for Ultra-Sensitive SERS Sensing

半导体表面增强拉曼散射(SERS)材料由于其低成本、高化学稳定性、生物相容性、结构多样性和可控性而备受关注。它们被认为是在实际应用中替代贵金属SERS基板的良好候选者。然而,半导体SERS基底的实际应用受到其低灵敏度和发展滞后的极大阻碍。最近我们研究小组提出了一种利用稀土元素镱(Yb)掺杂制备半导体TiO_(2)基底材料,这种方法可以实现对二氧化钛的几何和电子结构调制,并且获得了对4-巯基苯甲酸(4-MBA)分子极大的SERS增强。相较于未掺杂的TiO_(2),Yb-TiO_(2)表现出更加优良的SERS增强效果,根据Lombardi等提出的半导体SERS增强理论,增强是通过PICT机制中的Herzberg-Teller耦合,取决于吸附分子和基底能级匹配的程度。

Semiconductor surface-enhanced Raman scattering(SERS)materials have attracted much attention due to their low cost,high chemical stability,and biocompatibility.However,the practical application of semiconductor substrates is greatly hindered by its low sensitivity.Recently,our research group proposed a TiO_(2)material doped with rare earth element ytterbium(Yb).Compared with undoped TiO_(2),Yb-TiO_(2)exhibits better SERS enhancement effect.According to the semiconductor SERS enhancement theory proposed by Lombardi,the enhancement is through the Herzberg-Teller coupling in the PICT mechanism and depends on how well the adsorbed molecules and substrate energy levels match.