A blue organic near infrared (NIR) absorbing sensitizer, AP25, is investigated for use in broadly absorbing dye-sensitized solar cells (DSCs). AP25 shows solar-to-electric conversion with an onset near 900 nm in DSC devices and a photocurrent near 25 mA cm⁻² when co-sensitized. An all-organic SSM-DSC device reaches 10.3% PCE.

A novel metal-free quinoxaline-based molecular framework with a dual donor and dual acceptor (DD-π-AA) motif has been introduced. Four sensitizers (AP6, AP8, AP9, and AP12) have been synthesized and fully characterized via UV–Vis absorption, cyclic voltammetry, density functional theory (DFT) calculations, time-correlated single photon counting (TCSPC), and in dye-sensitized solar cell (DSC) devices. Structural modifications to both the donor and acceptor/anchor regions were evaluated via structure–property relationships without altering the quinoxaline π-bridge. Through careful dye design, a broadly absorbing near-infrared (NIR) sensitizer extending electricity production to 800 nm is realized in DSC devices. Ground- and excited-state oxidation potentials were measured to show energetically favorable charge transfer events. Importantly, the dye structure was found to have a strong influence on dye energetics in different environments with structural elements allowing for either similar or dramatically different solution versus film measurements. The DSC device electrolyte was also found to have a significant influence on dye energetics as well. Electron transfer events were probed for each dye with DSC device measurements and with TCSPC studies. The results are correlated to the dye structures.

Donor–π-bridge–acceptor dyes with thiophene have been shown to bind I₂ leading to diminished dye-sensitized solar cell performances relative to furan based analogues.