Di-branched di-anchoring organic dyes for dye-sensitized solar cells

Bis‐Donor–Bis‐Acceptor Tribranched Organic Sensitizers for Dye‐Sensitized Solar Cells

“…Upon addition of a small amount of HCl, the spectrum remains unchanged, confirming that both dyes are present as carboxylic acids. [9] This picture was con- Table 1. Absorption and emission parameters of TB-1 and TB-2 compared to reference dyes.…”

“…We have shown that the dibranched dye DB-1 (Scheme 1) offers improved optical properties (higher molar extinction coefficients and red-shifted absorption), increased photocurrent, and enhanced stability compared to its monobranched analogues. [9] Recently, a porphyrin posScheme 1. Reference photosensitizers.…”

“…Triarylamine has been by far the most widely used D core. [8] In the search for improved optical and structural properties, we, [9] and others, [10,11] have recently introduced a novel model class of dibranched dianchoring organic sensitizers composed of one donor and two anchoring groups (A-π-D-π-A). We have shown that the dibranched dye DB-1 (Scheme 1) offers improved optical properties (higher molar extinction coefficients and red-shifted absorption), increased photocurrent, and enhanced stability compared to its monobranched analogues.…”

First Principle Modelling of Materials and Processes in Dye-Sensitized Photoanodes for Solar Energy and Solar Fuels

“…Additionally, the collective orientation of adsorbed dyes on the semiconductor surface strictly depends on the anchoring motif, possibly affecting the rate and effectiveness of parasitic recombination reactions [160][161][162]. Finally, the sensitizer's grafting group should establish a stable binding of the dye onto the metal oxide surface, thus ensuring long-term stability of the cell [163][164][165]. Investigation of the adsorption of organic dyes onto TiO 2 cluster models [161,162,166], has largely shown that the bidentate bridging adsorption mechanism with proton transfer to a nearby surface oxygen is the energetically favored one (Figure 6), while the monodentate anchoring is usually predicted to be less stable, although some dependency on the employed methodology can be outlined [166], For Ru(II) sensitizers different adsorption modes onto the TiO 2 surface can be found: while homoleptic dyes, such as N3 or N719, can adsorb on TiO 2 using carboxylic anchoring groups residing on different bipyridine ligands and hence using up to three carboxylic groups (Figure 6c) [159,167], heteroleptic dyes, e.g., N621, C106, or Z907, necessarily adsorb via carboxylic groups residing on the same bipyridine (two carboxylic groups, Figure 6d) [168,169].…”

Zinc Porphyrins Possessing Three p-Carboxyphenyl Groups: Effect of the Donor Strength of Push-Groups on the Efficiency of Dye Sensitized Solar Cells

“…The mode of attachment of sensitizer to the semiconductor surface affects the efficiency of the electron-transfer at the dye-semiconductor interface [18][19][20][21]. Organic and phthalocyanine dyes with two anchoring groups are found to be more efficient and stable compared to their single anchoring group counterparts [22,23]. Porphyrins with different anchoring groups through different Following our long-term interest in porphyrin-sensitized solar cells [31][32][33][34][35][36][37][38], we have shown that multi-anchoring porphyrins serve as proficient, stable, and cost-effective sensitizers in DSSCs [39][40][41].…”