A series of new push–pull organic dyes incorporating electron-deficient pyrimidine as the π-spacer have been synthesized, characterized, and used as the sensitizers for dye-sensitized solar cells (DSSCs). In comparison with the model compound M-TP, which adopts phenylene as the π-spacer, the tailor-made dyes display enhanced spectral responses in the red portion of the solar spectrum. Through the introduction of two hexyloxy chains on the diphenylthienylamine donor, the DSSC employing dye OHexDPTP exhibited high power conversion efficiency up to 7.64% under AM1.5G irradiation.

A series of new porphyrins (LWP1–4) for dye-sensitized solar cells (DSSCs) were prepared by attaching pyrene or a 4-dimethylaminophenyl group in combination with anthracene to modify the porphyrin core. Fundamental studies showed that incorporation of these moieties renders feasible tuning of spectral and redox properties of the porphyrins. Significantly, DSSCs adopting the LWP1 dye exhibit energy conversion up to 800 nm without compromising the overall efficiency. This achievement is attributed to the collective effects of the broadened and red-shifted IPCE spectra, elevated energy levels at the excited states of the dyes, suitable dye soaking processes, and suitable electron-donating substituents.