Design and Performance of Small‐Molecule Donors with Donor–π‐Acceptor Architecture Toward Vacuum‐Deposited Organic Photovoltaics Having Heretofore Highest Short‐Circuit Current Density

Abstract

AbstractThe development of high‐performance organic photovoltaic materials is of crucial importance for the commercialization of organic solar cells (OSCs). Herein, two structurally simple donor‐π‐conjugated linker‐acceptor (D‐π‐A)‐configured small‐molecule donors with methyl‐substituted triphenylamine as D unit, 1,1‐dicyanomethylene‐3‐indanone as A unit, and thiophene or furan as π‐conjugated linker, named DTICPT and DTICPF, are developed. DTICPT and DTICPF are facilely prepared via a two‐step synthetic process with simple procedures. DTICPF with a furan π‐conjugated linker exhibits stronger and broader optical absorption, deeper highest occupied molecular orbital (HOMO) energy levels, and better charge transport, compared to its thiophene analog DTICPT. As a result, vacuum‐deposited OSCs based on DTICPF: C70 show an impressive power conversion efficiency (PCE) of 9.36% (certified 9.15%) with short‐circuit current density (Jsc) up to 17.49 mA cm−2 (certified 17.56 mA cm−2), which is the highest Jsc reported so far for vacuum‐deposited OSCs. Besides, devices based on DTICPT: C70 and DTICPF: C70 exhibit excellent long‐term stability under different aging conditions. This work offers important insights into the rational design of D‐π‐A configured small‐molecule donors for high efficient and stable vacuum‐deposited OSCs.