Photo-stable substituted dihydroindolo[2,3-b]carbazole-based organic dyes: tuning the photovoltaic properties by optimizing the pi structure for panchromatic DSSCs
2014 (English)In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 70, no 43, 8122-8128 p.Article in journal (Refereed) Published
Three dihydroindolo[2,3-b]carbazole (DDC) donor based organic dyes (DDC6-DDC8) with long conjugated systems were successfully synthesized and characterized by optical, electrochemical, computational analysis, and photovoltaic methods. It was found that the elongated pi system as well as the high molar extinction coefficients (4.2-5.3 M-1 cm(-1)) sufficiently reinforced the light harvesting ability with the IPCE response of one dye DDC8 extended to 850 nm, which resulted in large J(sc) of these dyes based devices (high as 16.41 mA cm(-2)). The attached alkyl chains suppress the dark current to some extent, resulting the DDC6 and DDC7 devices in high V-oc, while DDC8 displayed low V-oc, because BTD in DDC8 could attract the iodine ion, which could accelerate the charge recombination. Among the three dyes, DDC7 displayed the best performance with an eta value 6.53% under 4 mu m thick scattering layer (condition 1+1), which was boosted to 7.49% under 8 mu m thick scattering layer (condition 1+2). The photo-stability measurements indicated that all the three dyes are fairly photo-stable.
Place, publisher, year, edition, pages
2014. Vol. 70, no 43, 8122-8128 p.
Photo-stable, Dihydroindolo, Carbazole, Panchromatic, DSSCs
IdentifiersURN: urn:nbn:se:kth:diva-156111DOI: 10.1016/j.tet.2014.08.016ISI: 000343344500040ScopusID: 2-s2.0-84907452452OAI: oai:DiVA.org:kth-156111DiVA: diva2:777941
QC 201501092015-01-092014-11-212015-01-09Bibliographically approved