Design and Photo-functions of Self-assembled Nanolaminate Films

在本项目中，我们研究了介孔二氧化硅(MPS)和二氧化钛纳米片(TNS)的堆积杂化薄膜，每个薄膜分别含有卟啉染料(TMPyP)和甲基紫精(MV^&lt；2+&gt；)。在紫外光照射下，TMPyP发生单电子氧化，同时生成一个电子还原的mV^&lt；2+&gt；也就是说，结果表明电子通过这些无机薄膜的界面转移。本文从无机界面产生电流的角度出发，研究了沉积在FTO电极上的MPS/TNS杂化膜，将(MPS-TMPyP)/(TNS-MV&lt；2+&gt；)杂化膜与铂工作电极和Ag/AgCl参比电极一起浸泡在CH3CN中，通过测量紫外光下的光电流进行了分析。在施加负过孔电压-0.4V时，通过…观察到从FTO电极到MPS-TMPyP的阴极电流，尽管很弱H-TNS导带较多。为了观察特定的电流，尝试了一种反向堆积的(TNS)/(MPS-TMPyP)杂化薄膜，其中通过施加正的VIES电压从TNS中间层去除电子受体MV^lt；2+。通过紫外光照射反向堆积的薄膜，强大的阳极光电流通过无机界面进入FTO电极。在光谱观察的基础上，约60%的光电流诱导TMPyP的单电子氧化生成相应的单电子氧化物种，由此产生的电荷分离在该体系中相当稳定，并能长期存活。例如，在充气条件和环境温度下，形成的单电子氧化的TMPyP和还原的单电子MV^&lt；2+&gt；保持数小时。特别是在除氧条件下，电荷分离的半衰减期为&gt；几天。目前，该系统正在研究将适当的有机染料的可见光敏化电荷分离扩展到可见光敏化电荷分离，放热电子转移到TNS半导体的导带。较少

In the present project a stacking hybrid film of mesoporous silica (MPS) and titania nanosheets (TNS) has been investigated, each of which include separately porphyrin dye (TMPyP) and methyl viologen (MV^<2+>), respectively. Under UV light irradiation, thus obtained hybrid film exhibits one electron oxidation of TMPyP accompanied by the simultaneous generation of one electron reduced MV^<2+>. That is, the result suggests an electron transfer through the interface of these inorganic thin films. In this year, the MPS/TNS hybrid film deposited on a FTO electrode was studied from the point of the generation of electric current through the inorganic interface.(MPS-TMPyP)/(TNS-MV^<2+>) hybrid film on the FTO electrode was immersed in CH_3CN together with Pt working and Ag/AgCl reference electrodes, and analyzed by measuring the photocurrent under UV light. On applying a negative vias voltage, -0.4V, a cathodic current, though weak, has been observed from the FTO electrode to MPS-TMPyP throug … More h TNS conduction band. For the observation of definite electric currents, an inversely stacked (TNS)/(MPS-TMPyP) hybrid film was attempted, where an electron acceptor, MV^<2+>, was removed from TNS interlayers by applying a positive vies voltage. By irradiation of the inversely stacked film by UV light, a strong anodic photocurrent flows through the inorganic interface into the FTO electrode. On the basis of spectroscopic observation, ca. 60% of the photocurrents induced the one-electron oxidation of TMPyP into the corresponding one-electron oxidized species.The resulting charge separation has been found to be quite stable and survived for a long period in this system. For instance, the formed one-electron oxidized TMPyP and the one-electron reduced MV^<2+> remain for several hours under the aerated conditions and ambient temperature. Especially under deaerated conditions the charge separation has a period of half decay of>several days. Now the present system is under the study for extending to a visible light sensitized charge-separation by visible light excitation of an appropriate organic dye with exothermic electron transfer to the conduction band of TNS semiconductor. Less