End-capped “thiophene-free” organic dye for dye-sensitized solar cell: Optimized donor, broadened spectra and enhanced open-circuit voltage

Influence of Different Molecular Design Strategies on Photovoltaic Properties of a Series of Triphenylamine-Based Organic Dyes for Dye-Sensitized Solar Cells: Insights from Theoretical Investigations

“…Apparently, the calculated V OC of dye 1 matches very well the experimentally measured value of dye DH-16 (900 mV). 28 Dye 2 shows a decreased V OC with respect to dye 1, owing to the fact that the exchange of the BTZ and CZ moieties induces more charge recombination, which is in accordance with the observation in the previous studies of dyes XY2 and XY3. 29 The V OC can be further reduced in dye 4 by replacing the CZ-based π-bridge in dye 1 with an electron-rich TT group.…”

“…It is obvious that a good agreement is found between the calculated result in dye 1 and the experimental measurement in dye DH-16. 28 Based on the maximum photocurrent density (J max ) and maximum photovoltage (V max ), the fill factor (FF) of these targeted dyes can be gained (see Table 3), corresponding to the ratio of J max V max and J SC V OC . It is clear that the predicted FF varies from 0.85 to 0.87, in reasonable agreement with the experimental result of 0.71 in known dye DH-16.…”

“…The electronic interaction between D and A moieties gives rise to strong intramolecular-charge-transfer (ICT) absorption bands, which contributes to capture the sunlight for light-to-electricity conversion. Recently, a new concept using a D–A−π–A configuration has been suggested as a novel highly efficient and stable photosensitive dyes, which is realized by bringing an auxiliary electron acceptor into the central π-spacer unit under D−π–A system for governing the energy levels and spectral response as well as increasing the photostability of photosensitizer. − Duan et al presented a D–A−π–A type organic dye ( DH-16 ) by using benzothiadiazole (BTZ) as an auxiliary acceptor, which achieved an enhanced PCE of 6.76% in comparison to 5.06% observed in the D−π–A structured parent compound . Zhang et al reported another D–A−π–A-type dye ( XY2 ) possessing an auxiliary acceptor (BTZ) and cyclopentadithiophene (CPDT)-based π-spacer, which showed a high PCE of 6.89% under 95% sunlight illumination, along with the open-circuit photovoltage of 0.929 V, short-circuit photocurrent density of 10.14 mA cm –2 , and fill factor of 0.698 .…”

“…a Experimental findings observed in dye DH-16 28. The Journal of Physical Chemistry C pubs.acs.org/JPCC Article…”

Theoretical Study of the Effect of π-Bridge on Optical and Electronic Properties of Carbazole-Based Sensitizers for DSSCs

“…Metal-free organic sensitizers have used a variety of organic electron donor compounds presenting an excellent performance, due to the ability to excite its electrons [12], such as coumarin [13], carbazole [14], indoline [15,16], phenothiazine [17], and triphenylamine [18,19]. The use of thiophene [20], benzene [21], dioxythiophene [22], and benzothiadiazole [23] on the π-bridge have been studied extensively. Cyanoacrylic acid and alkoxysilane [24] have been widely used as anchorage groups with excellent results [8].…”