Synthesis and applications of new triphenylamine dyes with donor–donor–(bridge)–acceptor structure for organic dye-sensitized solar cells

Four novel asymmetric triphenylamine dyes configured with donor–donor–acceptor (D–D–A) and donor–donor–bridge–acceptor (D–D–π–A) structures were synthesized and applied to organic dye-sensitized solar cells. The terminal methoxy group in the donor part and the furane-bridge unit contributed to the wider absorption region and enhanced electron life time, resulting in a higher photocurrent density (Jsc), open-circuit voltage (Voc), and overall conversion efficiency (η). Among the synthesized dyes, the SK2-based DSSC showed the highest conversion efficiency of 5.57% (Jsc = 10.41 mA cm−2, Voc = 729 mV, and FF = 0.73) caused by the synergetic effect of the methoxy group and the furane-bridge unit.