Two derivatives of tetraphenylethene (TPE) were synthesized through one step cross McMurry coupling reaction. Both luminogens exhibit aggregation-induced emission (AIE) and crystallization induced emission enhancement (CIEE). The emissions of both luminogens could be switched between blue and green through reversible modulation of morphology with thermal, organic solvent fuming and mechanical stimuli. Thus we provide a possible design strategy for emission switching materials.
SHI JunQingZHAO WeiJunLI CuiHongLIU ZhengPingBO ZhiShanDONG YuPingDONG YongQiangTANG Ben Zhong
6,7-Dialkoxy-2,3-diphenylquinoxaline based narrow band gap conjugated polymers, poly[2,7-(9-octyl-9H- carbazole)-alt-5,5-(5,8-di-2-thinenyl-(6,7-dialkoxy-2,3-diphenylquinoxaline))] (PCDTQ) and poly[2,7-(9,9-dioctylfluorene)- alt-5,5-(5,8-di-2-thinenyl-(6,7-dialkoxy-2,3-diphenylquinoxaline))] (PFDTQ), have been synthesized by Suzuki polycondensation. Their optical, electrochemical, transport and photovoltaic properties have been investigated in detail. Hole mobilities of PCDTQ and PFDTQ films spin coated from 1,2-dichlorobenzene (DCB) solutions are 1.0 X 10-4 and 4.1 X 10-4 cm2 V-1 s-l, respectively. Polymer solar cells were fabricated with the as-synthesized polymers as the donor and PC61BM and PC7 IBM as the acceptor. Devices based on PCDTQ:PC71BM (1:3) and PFDTQ:PC7 IBM (1:3) fabricated from DCB solutions demonstrated a power conversion efficiency (PCE) of 2.5% with a Voc of 0.95 V and a PCE of 2.5% with a Voof 0.98 V, respectively, indicating they are promising donor materials.