Nguyen The-Duy, Lan Yen-Po, Wu Chun-Guey
Department of Chemistry and Research Center for New Generation Photovoltaics, National Central University , Jhong-Li 32001, Taiwan, ROC.
Inorg Chem. 2018 Feb 5;57(3):1527-1534. doi: 10.1021/acs.inorgchem.7b02862. Epub 2018 Jan 22.
Four thiocyanate-free ruthenium sensitizers (DUY24-DUY27) containing 2-thienylpyridine moiety as cyclometalating core were synthesized for dye-sensitized solar cell (DSC) application. To the best of our knowledge, DUY24-DUY27 are four best-efficiency sensitizers having 42%-65% higher efficiencies compared to those of the published sensitizers comprising the same type of the cyclometalating ancillary ligands. The significant characteristic of DUY24-DUY27 is their β-lowest unoccupied spin orbital (β-LUSO) distributes remarkably on the cyclometalating ligands, especially on the soft sulfur atom, which strengthens the interaction between the oxidized dye and iodide ion for efficient dye regeneration. The photovoltaic performance of DUY24-DUY27-based DSCs supports that the dye regeneration (therefore the short-circuit photocurrent density (J) of the cell) can be improved by not only lowering the highest occupied molecular orbital energy level of the dye molecule but also distributing the β-LUSO properly on the soft atoms. The study provides an important new guide for designing high-efficiency ruthenium-based dyes for DSC application.
合成了四种不含硫氰酸盐的钌敏化剂（DUY24 - DUY27），其含有2 - 噻吩基吡啶部分作为环金属化核心，用于染料敏化太阳能电池（DSC）。据我们所知，与已发表的包含相同类型环金属化辅助配体的敏化剂相比，DUY24 - DUY27是四种效率最高的敏化剂，效率高出42% - 65%。DUY24 - DUY27的显著特征是其β - 最低未占据自旋轨道（β - LUSO）显著分布在环金属化配体上，尤其是在软硫原子上，这增强了氧化态染料与碘离子之间的相互作用以实现有效的染料再生。基于DUY24 - DUY27的DSC的光伏性能表明，不仅通过降低染料分子的最高占据分子轨道能级，而且通过在软原子上适当分布β - LUSO，可以提高染料再生（从而提高电池的短路光电流密度（J））。该研究为设计用于DSC应用的高效钌基染料提供了重要的新指导。
