Dye-sensitised solar cells based on metal complexes with pendant catecholate anchoring groups

强吸收光的金属配合物可以作为太阳能电池的基础。通过将这些金属配合物附着在半导体（如二氧化钛）的表面，光可以转换成电；被每个分子吸收的光的能量导致将一个电子注入半导体，从而产生电流。这些方法的有效性取决于几个因素，尤其是(i)分子与TiO2表面结合的强度，以及（ii）防止反电子转移，即注入的电子与染料分子重新结合，而不是产生电流。该项目旨在解决这两个领域。我们已经证明，与邻苯二酚（1,2-二羟基苯）基团连接在外围的金属配合物对TiO2表面的附着异常强烈，我们计划沿着这条路线制造更多的配合物，以研究它们在太阳能电池中作为敏化剂（电流发生器）的性能。通过将胺基附着在配合物的外围，可以（快速）提供一个电子来填补电荷注入后留下的空白，从而防止从TiO2向金属配合物的反电子转移，从而解决不希望的反电子转移问题。我们将沿着这条路线制备几种新的配合物，对它们的光物理和电化学特性进行详细的研究，然后确定它们在原型太阳能电池器件中的性能。希望新的配合物能够提供比现有系统更好的长期性能，因为它们与TiO2表面的结合非常紧密。

Metal complexes which absorb light strongly can be used as the basis of solar cells. By attachment of these metal complexes to the surface of a semiconductor such as titanium dioxide, light can be convertedsto electricity; the energy of the light absorbed by each molecule results in injection of an electron into the semiconductor which results in a current flow.The effectiveness of these depends on several factors, especially (i) how strongly the molecules bind to the TiO2 surface, and (ii) prevention of back electron-transfer, where the injected electron recombines with the dye molecule rather than generating an electric current. This project aims to address both of these areas. We have already shown that metal complexes with a catechol (1,2-dihydroxybenzene) group attached to the periphery attach exceptoinally strongly to the TiO2 surface, and we plan to make additional complexes along these lines to investogate their performance as sensitisers (generators of electric current) in solar cells. The problem of undesired back electron-transfer will be addressed by also attaching amine groups to the periphery of the complexes, which will (quickly) donate an electron to fill the gap left after charge injection, thereby preventing back electron-tramsfer from the TiO2 to the metal complex.We will prepare several new complexes along these lines, carry out a detailed study of their photophysical and electrochemical properties, and then determine how well they perform in prototypical solar cell devices. It is hoped that the new complexes will provide better long-term performance than existing systems because of their very tight binding to the TiO2 surface.