Novel A-π-D-π-A-type BODIPY dyads as small-molecule donors for solution-processed organic solar cells. Issue 8 (3rd February 2022)

• Record Type: Journal Article
• Authors: Xie, Bao; Yin, Lunxiang; Fan, Junmei; Liu, Chang; Li, Yanqin
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 8(2022)
• Page Start: 3248
• Page End: 3258
• Publication Date: 2022-02-03
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1tc04981j
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Two novel narrow-bandgap A-π-D-π-A-type BODIPY dyes were synthesized via a one-step Stille reaction with "D-π" segment at the β-site of BODIPY unit, where CTBDP -based device gave an impressive PCE of 5.85% with an excellent J sc of 17.70 mA cm −2 . Abstract : The boron dipyrromethane (BODIPY) unit has attracted interest due to its strong molar extinction coefficient and tunable electrochemical properties, and thus, currently, BODIPY-based organic photovoltaic materials featuring near-infrared absorption and deep HOMO levels are widely constructed and investigated. Herein, two novel A-π-D-π-A-type BODIPY small-molecule donors (SMDs), namely, CTBDP and DCTBDP, in which carbazole and indolo-[3, 2- b ]carbazole as the electron-donating core (D) connect the electron-withdrawing BODIPY moiety (A) with thiophene as a π-bridge, respectively, were designed and synthesized via Stille coupling reaction with a "D-π" segment at the β-site of BODIPY. CTBDP and DCTBDP exhibited a deep-lying HOMO level of −5.46 eV and −5.34 eV and narrow optical bandgap of 1.51 eV and 1.56 eV, respectively, together with a broad absorption in the range of 300–900 nm in films. Interestingly, the CTBDP -device exhibited an impressive PCE of 5.85% with an outstanding J sc of 17.70 mA cm −2 and V oc of 0.81 V, which are the highest PCE and J sc values reported to date for A–D–A-type BODIPY-SMDs for solution-processed OSCs. Our work demonstrates that carbazole/indolo[3, 2- b ]carbazole-BODIPY conjugated small molecules can simultaneously achieve a narrow bandgap and low HOMO level via their rational molecular design, which provides crucial guidance for the development of high-efficiency BODIPY-based photovoltaic materials in the future.