Novel Phenylene–Thiophene Oligomer Derivatives with Dibenzothiophene 5,5-Dioxide Core: Synthesis, Characterization, and Applications in Organic Solar Cells

Abstract

Donor–acceptor–donor oligomers with dibenzothiophene 5,5-dioxide core and end-cap phenylene–thiophene substitutes were newly synthesized. New oligomers were characterized by UV–vis absorption and photoluminescence spectroscopy, cyclic voltammetry, and applied as electron donor in bulk-heterojunction solar cells. The results indicate that phenylene–thiophene oligomer derivatives containing dibenzothiophene 5,5-dioxide moiety are appraised to be valuable electron donors.

Synthesis of novel thiophene‐phenylene oligomer derivatives with a dibenzothiophene‐5,5‐dioxide core for use in organic solar cells

“…The results are summarized in Table 1. The detailed analyses are described in elsewhere 19. The optical band gap of 37HPTDBTSO was determined from the absorption onsets of the film and was found to be 2.52 eV.…”

“…All reactions involving air‐ or moisture‐sensitive compounds were carried out in a dry reaction vessel under a positive pressure of nitrogen. Because the details of the synthesis of 37HPTDBTSO have been described elsewhere 19, only an outline is given here (see Fig. 1b).…”

“…Recently, we synthesized a donor–acceptor–donor thiophene‐containing oligomer, 3,7‐bis[5‐(4‐ n ‐hexylphenyl)‐2‐thienyl]dibenzothiophene‐5,5‐dioxide (37HPTDBTSO, as shown in Fig. 1a) 19. In a previous study, we applied this new oligomer to OSCs for the first time, and it was found that the oligomer is a valuable electron donor.…”

Bulk-Heterojunction Solar Cells Based on Mixed Donorsof P3HT and Phenylene–Thiophene Oligomer Derivative

“…These are regarded to be the reason why the V oc of the solar cell based on PCBM:37HPTDBTSO was as high as 0.81 V. The possible reason for the relatively low V oc of the solar cell based on PCBM：P3HT may be due to fact that chloroform was used as a solvent (31,32). This time all the devices were fabricated using chloroform as a solvent to make a fair comparison because 37HPTDBTSO was only soluble in chloroform (23,24). …”

Organic Solar Cells Based on PTB7:PC71BM with Cs2CO3 as a Cathode Buffer Layer

“…Organic thin-film solar cells are especially interesting owing to their outstanding characteristics in terms of low-cost fabrication, light weight, and flexibility [1][2][3][4][5]. Tang [6] first reported a heterojunction solar cell composed of an organic electron donor layer (organic p-type semiconductor) and an organic electron acceptor layer (organic n-type semiconductor) using vacuum deposition systems.…”