A Facile Planar Fused-Ring Electron Acceptor for As-Cast Polymer Solar Cells with 8.71% Efficiency

Abstract

A planar fused-ring electron acceptor (IC-C6IDT-IC) based on indacenodithiophene is designed and synthesized. IC-C6IDT-IC shows strong absorption in 500-800 nm with extinction coefficient of up to 2.4 × 10(5) M(-1) cm(-1) and high electron mobility of 1.1 × 10(-3) cm(2) V(-1) s(-1). The as-cast polymer solar cells based on IC-C6IDT-IC without additional treatments exhibit power conversion efficiencies of up to 8.71%.

An Alkylated Indacenodithieno[3,2‐b]thiophene‐Based Nonfullerene Acceptor with High Crystallinity Exhibiting Single Junction Solar Cell Efficiencies Greater than 13% with Low Voltage Losses

“…Among the highest performing NFAs, linear rod-like acceptor-donor-acceptor (A-D-A) structures incorporating fused ladder-type aromatics have attracted much interest. Common donor units include 4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene (IDT) [5][6][7][8][9] and 6,12-dihydro-dithienoindeno [10][11][12][13][14][15][16][17][18] In both cases, the fused core facilitates π-electron delocalization and improves the π-π stacking between molecules, hence enhancing the intrinsic charge carrier mobility.In 2015, Zhan and coworkers reported a new NFA, 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11--b′]dithiophene (ITIC) (Scheme 1), which is comprised an electron-donating IDTT-based core flanked by two electron-withdrawing units of 1,1-dicyanomethylene-3-indanone (IC), that exhibited a promising PCE of 6.8% at that time. [10] Since then, many strategies have been applied to modify the structure of ITIC in order to adjust the absorption spectra and energy levels to further improve the PCE, for example, by changing the side chains, [17,18] extending the conjugation length, [19][20][21][22] and substituting the end acceptor groups.…”

“…Among the highest performing NFAs, linear rod-like acceptor-donor-acceptor (A-D-A) structures incorporating fused ladder-type aromatics have attracted much interest. Common donor units include 4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene (IDT) [5][6][7][8][9] and 6,12-dihydro-dithienoindeno [10][11][12][13][14][15][16][17][18] In both cases, the fused core facilitates π-electron delocalization and improves the π-π stacking between molecules, hence enhancing the intrinsic charge carrier mobility.…”

Environmentally-friendly solvent processed fullerene-free organic solar cells enabled by screening halogen-free solvent additives

“…Great efforts have been made to improve the power conversion effi-ciencies (PCEs) of OSCs by utilizing novel materials and new processing methods over the past decades [1,[20][21][22][23][24][25][26][27][28][29][30][31]. Recently, high-performance non-fullerene acceptor materials, especially the small-molecular acceptors (SMAs), were successfully developed [32][33][34][35][36][37][38][39][40][41][42][43][44][45]. These SMAs materials exhibit excellent solubility in non-halogen solvents, such as o-xylene (XY), anisole and tetrahydrofuran (THF) [46], which have brought the possibility of fabricating high-performance non-fullerene OSCs using non-halogen solvent systems.…”

A New Electron Acceptor with meta‐Alkoxyphenyl Side Chain for Fullerene‐Free Polymer Solar Cells with 9.3% Efficiency

“…For example, IC‐C6IDT‐IC with four n ‐hexyl as side chains, exhibited a PCE of 8.71%,32 and ITIC‐Th with four 2‐thienyl groups showed a PCE of up to 9.6% with 1‐chloronaphthalene additive 33. However, from the reported ITIC derivatives, no attention was paid to using alkoxyphenyl replacing alkylphenyl of ITIC, indeed, alkoxyphenyl group seemed more easily synthesized via simple etherification, much lower cost, and more coplanar compared to its alkyl counterpart.…”