卟啉/TiO2界面的相互作用研究

采用吸收光谱、荧光光谱和瞬态光伏技术研究了卟啉/TiO2体系的吸收光特性、荧光特性和光伏特性, 并研究了卟啉和TiO2之间的界面相互作用. 研究结果表明, 卟啉环在与钬原子结合前后与TiO2之间的作用不同, TiO2的粒径也影响界面的相互作用. 卟啉与粒径为10 nm的TiO2作用后, 能级发生了简并, 同时带隙发生了红移. 卟啉与粒径为56 nm的TiO2相互作用后只有特征吸收峰发生红移, 带隙和峰的数量几乎未发生变化. 这说明在粒径为10 nm的TiO2与卟啉的大π键之间出现了离域的相互作用, 这也被荧光光谱和瞬态光伏曲线所证实.

Studies on Interaction of Interface Between Porpyrin and TiO2

The absorption,photoluminescence and photovoltaic characteristics of porphyrin/TiO2 system were studied with absorption spectra,photoluminescence spectra and transient photovoltage technology,respectively,and the interaction of interface between porphyrin and TiO2 was also studied.The results obtained indicate that the interaction was different before and after Ho atom joined in porphyrin ring,the size of TiO2 also affected the interaction.When porphyrin was affected by TiO2 with 10 nm in diameter,its energy level was degenerated and band edge of porphyrin was red shifted,while it was affected by TiO2 with 56 nm and its energy level had little change.It indicates that the delocalizing interaction existed between the big pi bond of porphyrin and surface of TiO2 with 10 nm in diameter.The delocalizing interaction was also demonstrated via fluorescence spectra and transient photovoltage curves.Results are significant for the effective photo-electric conversion and study on the transfer of photogenerated carriers.