Large π-Aromatic Molecules as Potential Sensitizers for Highly Efficient Dye-Sensitized Solar Cells

摘要: Recently, dye-sensitized solar cells have attracted much attention relevant to global environmental issues. Thus far, ruthenium(II) bipyridyl complexes proven be the most efficient TiO(2) sensitizers in cells. However, a gradual increment highest power conversion efficiency has been recognized past decade. More importantly, considering that ruthenium is rare metal, novel dyes without metal or using inexpensive are desirable for highly Large pi-aromatic molecules, such as porphyrins, phthalocyanines, and perylenes, important classes of potential cells, owing their photostability high light-harvesting capabilities can allow applications thinner, low-cost Porphyrins possess an intense Soret band at 400 nm moderate Q bands 600 nm. Nevertheless, poor properties relative limited cell performance porphyrin-sensitized Elongation pi conjugation loss symmetry porphyrins cause broadening red shift absorption together with increasing intensity band. On basis strategy, improved intensively by enhanced light absorption. Actually, some push-pull-type disclosed remarkably (6-7%) was close complexes. Phthalocyanines exhibit strong around 300 700 redox features similar porphyrins. Moreover, phthalocyanines transparent over large region visible spectrum, thereby enabling possibility them "photovoltaic windows". poor, aggregation lack directionality excited state. Novel unsymmetrical zinc phthalocyanine "push" "pull" groups made it possible reduce on surface, tune level state, strengthen electronic coupling between core surface. As result, up 3.5% achieved. Perylenes well-known chemically, thermally, photophysically stable used various optical devices applications. remained low compared other organic dyes. The origin electron-donating abilities which makes difficult inject electrons from singlet state perylenes conduction electrode efficiently. Strongly perylene carboxylic acid derivatives amine substituents allowed us increase approximately 7% perylene-sensitized molecule-sensitized could significantly if larger near-infrared developed.