文献类型：期刊文献

英文题名：Constructing High-Efficiency D-A-π-A-Featured Solar Cell Sensitizers: a Promising Building Block of 2,3-Diphenylquinoxaline for Antiaggregation and Photostability

作者：Pei, Kai[1,2];Wu, Yongzhen[1,2];Islam, Ashraful[3];Zhang, Qiong[1,2];Han, Liyuan[3];Tian, He[1,2];Zhu, Weihong[1,2]

机构：[1]E China Univ Sci & Technol, Key Lab Adv Mat, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Inst Fine Chem, Shanghai 200237, Peoples R China;[3]Natl Inst Mat Sci, Photovolta Mat Unit, Tsukuba, Ibaraki, Japan

年份：2013

卷号：5

期号：11

起止页码：4986

外文期刊名：ACS APPLIED MATERIALS & INTERFACES

收录：;EI(收录号：20132616444121);WOS:【SCI-EXPANDED(收录号:WOS:000320484000067)】；

基金：This work was financially supported by NSFC/China, National 973 Program (2013CB733700), the Oriental Scholarship, SRFDP 20120074110002, the Fundamental Research Funds for the Central Universities (WK1013002), STCSM (10dz2220500), Core Research for Evolutional Science and Technology (CREST) of the Japan Science and Technology Agency, and the Open Funding Project of State Key Laboratory of Luminescent Materials and Devices (SCUT).

语种：英文

外文关键词：solar cells; organic sensitizers; quinoxaline; antiaggregation; photostability

摘要：Controlling the sensitizer morphology on a nanocrystalline TiO2 surface is beneficial to facilitating electron injection and suppressing charge recombination. Given that the grafted alkyl chain on a pi-bridge thiophene segment for preventing pi aggregation can deteriorate its intrinsic photostability, we incorporate a promising building block of 2,3-diphenylquinoxaline as the additional acceptor to construct a novel D-A-pi -A-featured dye IQ(4), which exhibits several characteristics: (i) efficiently decreasing the molecular HOMO-LUMO energy gap by extending its absorption bands; (ii) showing a moderate electron withdrawing capability for an ideal balance in both promising photocurrent and photovoltage; (iii) endowing an ideal morphology control with strong capability of restraining the intermolecular aggregation and facilitating the formation of a compact sensitizer layer via two twisted phenyl groups grafted onto the quinoxaline unit. The coadsorbent-free dye sensitized solar cell (DSSC) based on dye IQ(4), exhibits very promising conversion efficiency as high as 9.24 +/- 0.05%, with a short-circuit current density (J(sc)) of 17.55 mA cm(-2), an open circuit voltage (V-oc) of 0.74 V, and a fill factor (FF) of 0.71 under AM 1.5 illumination (100 mW cm(-2)). IQ(4)-based DSSC devices with an ionic liquid electrolyte can keep constant performance during a 1000 h aging test under 1 sun at 60 degrees C. Because of spatial restriction, the two phenyl groups grafted onto the additional electron-withdrawing quinoxaline are demonstrated as efficient building blocks, not only improving its photostability and thermal stability but also allowing it to be a successful antiaggregation functional unit As a consequence, the incorporated 2,3-diphenylquinoxaline unit can realize a facile structural modification for constructing organic coadsorbent-free D-A-pi-A-featured sensitizers, thus paving a way to replace the common, stability-deleterious grafted alkyl chain on the thienyl bridge.