Shiau, S.-Y.S.-Y.ShiauChang, C.-H.C.-H.ChangChen, W.-J.W.-J.ChenWang, H.-J.H.-J.WangJeng, R.-J.R.-J.JengLee, R.-H.R.-H.LeeRU-JONG JENG2018-09-102018-09-102015http://www.scopus.com/inward/record.url?eid=2-s2.0-84922369333&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/390572A series of novel triazine-cored, star-shaped, conjugated molecules have been synthesized as donor materials for small molecule based organic solar cells. The structural features of these star-shaped molecules include a planarized triazine as the central core, 2,5-thienyl diketopyrrolopyrrole and 1,4-phenylene diketopyrrolopyrrole as the π-conjugated bridge, and tert-butyl-substituted triphenylamine and tert-butyl-substituted carbazole as the role of end groups and donor units. Photovoltaic properties of the solar cells based on the star-shaped molecule with 2,5-thienyl diketopyrrolopyrrole branches were much better than those of the solar cells based on the one with 1,4-phenylene diketopyrrolopyrrole branches. A power conversion efficiency of 1.57%, a short-circuit current density of 6.34 mA/cm2, an open-circuit voltage of 0.73 V, and a fill factor of 0.34 were observed for the organic solar cell based on the star-shaped molecule with 2,5-thienyl diketopyrrolopyrrole branches. © 2014 Elsevier Ltd. All rights reserved.Bulk heterojunction cell; Conjugated molecules; Diketopyrrolopyrrole; Photovoltaic performance; Star-shaped molecules; Triazine[SDGs]SDG7Heterojunctions; Molecules; Open circuit voltage; Organic polymers; Solar power generation; Stars; Synthesis (chemical); Bulk heterojunction; Conjugated molecules; Diketopyrrolopyrroles; Photovoltaic performance; Star-shaped molecules; Triazine; Solar cellsjournal article10.1016/j.dyepig.2014.12.007