New Paradigm in Molecular Engineering of Sensitizers for Solar Cell Applications
New Paradigm in Molecular Engineering of Sensitizers for Solar Cell Applications
复制标题
DOI：
10.1021/ja9002684
复制
发表时间：
2009-04-29
影响因子：
15
通讯作者：
Graetzel, Michael
中科院分区：
文献类型：
--
作者：
Bessho, Takeru;Yoneda, Eiji;Graetzel, Michael
设计并开发了一种新型的无硫氰酸根的环合钌太阳能电池敏化剂。锚定到纳米TiO 2薄膜后，它表现出显着的入射单色光-电流转换效率为83%。采用基于液体的电解质的太阳能电池表现出17 mA/cm（2）的短路光电流密度、800 mV的开路电压和0.74的填充因子，对应于在标准AM 1.5太阳光下10.1%的总转换效率。为了了解环化钌敏化剂的结构，电子和光学性质，我们使用密度泛函理论（DFT）和含时DFT（TDDFT）进行了研究。结果表明，HOMO主要位于钌和环金属化配体上，而LUMO则位于4-羧酸-4 '-羧酸酯-2，2'-联吡啶上。分子轨道分析证实了氧化还原电位的实验分配，和TDDFT计算允许分配的可见吸收带。目前的研究结果提供了新的设计标准，为下一代的钌敏化剂，并有助于促进工程的新敏化剂，有效地与I-/I-3（-）氧化还原对的广泛兴趣。
A novel thiocyanate-free cyclometalleted ruthenium sensitizer for solar cells is designed and developed. Upon anchoring to nanocrystalline TiO2 films, it exhibits a remarkable incident monochromatic photon-to-current conversion efficiency of 83%. The solar cell employing a liquid-based electrolyte exhibits a short circuit photocurrent density of 17 mA/cm(2), an open circuit voltage of 800 mV, and a fill factor of 0.74, corresponding to an overall conversion efficiency of 10.1% at standard AM 1.5 sunlight. To understand the structural, electronic, and optical properties of the cyclometalleted ruthenium sensitizer, we have investigated using density functional theory (DFT) and time-dependent DFT (TDDFT). Our results show the HOMO is located mostly on ruthenium and cyclometalated ligand, while the LUMO is on 4-carboxylic acid-4'-carboxylate-2,2'-bipyridine. Molecular orbitals analysis confirmed the experimental assignment of redox potentials, and TDDFT calculations allowed assignment of the visible absorption bands. The present findings provide new design criteria for the next generation of ruthenium sensitizers and help foster widespread interest in the engineering of new sensitizers that interact effectively with the I-/I-3(-) redox couple.