New Approaches to More Effective Photosensitizers for TiO2-Based Solar Cells

本项目致力于基于Ru（II）多吡啶基序的二氧化钛敏化新染料的合理设计和合成。染料的性质与Ru（II）核周围的配体的性质直接相关。通过引入具有更多离域π-体系和含有非配位电负性氮的配体，染料的吸光度将扩展到近红外区域。基于涉及配体LUMO能量的理论预测，将使用Friedlaender和Pfitzinger方法制备几类二齿和三齿配体。羧基将被引入4-和/或4 '-位，以便将染料锚在半导体表面上。将制备桥接配体以允许形成多核系统，所述多核系统被设计成在宽范围的太阳光谱内保持强吸收。目标染料将被吸附在太阳能电池的表面上，从而被纳入原型太阳能电池中。入射光子-电流效率将在350-1150 nm范围内测量。染料敏化太阳能电池（DSSC）作为现有硅基太阳能电池的低成本、耐用替代品具有很大的前景。DSSC的关键组分是染料敏化剂，其应在太阳光谱的整个有用范围（350-950 nm）内强烈吸收光。在有机和高分子化学项目的支持下，休斯顿大学化学系的兰多夫P. Thummel教授正在设计和制备新的染料，这些染料有望在广泛的太阳光谱范围内提供强吸收。开发更有效的光敏剂将有助于太阳能电池技术，并可能对我们利用光的方式具有进一步的深远意义。高效、经济地将太阳能转化为电能将有利于人类，促进能源独立，保护自然资源，避免环境污染。

This project addresses the rational design and synthesis of new dyes for the sensitization of titanium dioxide based on the Ru(II) polypyridine motif. The properties of the dye are directly related to the properties of the ligands which surround the Ru(II) core. The absorbance of the dyes will be extended into the near IR region through the incorporation of ligands having more delocalized pi-systems and containing non-coordinated electronegative nitrogens. Based on theoretical predictions involving ligand LUMO energies, several classes of bidentate and tridentate ligands will be prepared using Friedlaender and Pfitzinger methodologies. Carboxyl groups will be introduced into the 4- and/or 4'-positions in order to anchor the dye to the semiconductor surface. Bridging ligands will be prepared to allow the formation of polynuclear systems designed to maintain strong absorbance over a wide range of the solar spectrum. Target dyes will be adsorbed on the surface of anatase and thus incorporated into a prototype solar cell. Incident photon-to-current efficiencies will be measured over the range of 350-1150 nm.Dye-sensitized solar cells (DSSCs) hold great promise as low cost, durable alternatives to existing silicon-based solar cells. The key component of a DSSC is the dye sensitizer that should absorb light strongly over the entire useful range of the solar spectrum (350-950 nm). With the support of the Organic and Macromolecular Chemistry Program, Professor Randolph P. Thummel, of the Department of Chemistry at the University of Houston, is designing and preparing new dyes expected to provide strong absorbance over a wide range of the solar spectrum. The development of more efficient photosensitizers will be useful in solar cell technology and may have further reaching significance in the way we utilize light. The efficient and economical conversion of solar to electrical energy will benefit mankind by promoting energy independence, preserving natural resources, and avoiding environmental pollution.