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

本项目致力于基于Ru(II)多吡啶基元的二氧化钛增感新染料的合理设计和合成。染料的性质与Ru(II)核周围配体的性质直接相关。通过引入具有更多离域pi-系统和含有非配位电负性氮的配体，染料的吸收将扩展到近红外区域。基于有关配体LUMO能量的理论预测，将用Friedlaender和Pfitzinger方法制备几类双齿和三齿配体。羧基将被引入到4位和/或4‘位，以便将染料锚定到半导体表面。将准备桥联配体，以允许形成多核系统，以在广泛的太阳光谱范围内保持强吸收。目标染料将被吸附在锐钛矿表面，从而被整合到原型太阳能电池中。入射光子到电流的效率将在350-1150 nm的范围内进行测量。染料敏化太阳能电池(DSC)作为现有硅基太阳能电池的低成本、耐用的替代品具有很大的前景。DSSC的关键组件是染料增感剂，它应该在整个太阳光谱的有用范围(350-950 nm)内强烈吸收光线。在有机化学和高分子化学计划的支持下，休斯顿大学化学系的兰道夫·P·图梅尔教授正在设计和制备新的染料，有望在广泛的太阳光谱范围内提供强吸收。更高效的光敏剂的开发将在太阳能电池技术中发挥作用，并可能对我们利用光的方式产生进一步的影响。高效、经济地将太阳能转换为电能，将促进能源独立、保护自然资源、避免环境污染，从而造福人类。

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.