IHIC

IHIC (CAS number 2127354-15-6), also known as 4TIC, has an acceptor–donor–acceptor (A–D–A) structure consisting of an electron-rich fused hexacyclic unit dithienocyclopentathieno[3,2-b]thiophene core and two electron withdrawing 1,1-dicyanomethylene-3-indanone (IC) terminal units. The rigid planar structure of dithienocyclopentathieno[3,2-b]thiophene promotes inter-molecular charge transport.

IHIC exhibits strong absorption in the NIR range of 600–900 nm with extinction coefficient of up to 6 ×10⁵ m⁻¹ cm⁻¹and high electron mobility of up to 2.4 × 10^-3 cm² V⁻¹ s⁻¹.

When PTB7-Th was used as the low band-gap donor polymer with IHIC as the narrow-bandgap non-fullerene acceptor, excellent device performance was demonstrated with a high power conversion efficiency (PCE) of 9.77%. The active layer exhibits strong NIR absorption but weak visible absorption while giving the device a semi-transparent nature.

Device structure: ITO/ZnO/PTB7-Th: IHIC/MoO3/Au(1 nm)/Ag(15nm)[1]

Chemical Structure

Literature and Reviews

1. Fused Hexacyclic Non fullerene Acceptor with Strong Near Infrared Absorption for Semitransparent Organic Solar Cells with 9.77% Efficiency, W. Wang et al., Adv. Mater., 1701308 (2017); DOI: 10.1002/adma.201701308.
2. Non fullerene Acceptors for Semitransparent Organic Solar Cells, S. Dai et al., Adv. Energy Mater., 1800002 (2018); DOI: 10.1002/aenm.201800002.
3. Near-infrared organic photoelectric materials for light harvesting systems: Organic photovoltaics and organic photodiodes, B. Xie et al., InfoMat., 2, 57–91 (2020); DOI: 10.1002/inf2.12063.
4. Trendsetters in High-Efficiency Organic Solar Cells: Toward 20% Power Conversion Efficiency, M. Upama et al., Sol. RRL, 1900342 (2019); DOI: 10.1002/solr.201900342.