Data for: Highly efficient ternary polymer solar cells based on a novel double-cabled third component with the same molecular fragments of donor and acceptor moieties

Published: 31-03-2020| Version 1 | DOI: 10.17632/ngf25cg8pd.1
Zhan'ao Tan


Organic thin film solar cells have attracted wide attention because of their low-cost, flexibility, light-weight and solution-processiblity. With continuous efforts in material designing and device engineering, the power conversion efficiency (PCE) of the polymer solar cells (PSCs) has beyond 15%. The novel non-fullerene acceptors with broad absorption spectra and high electron mobility play a key role for PCE enhancement. However, the low absorption of non-fullerene materials in the short-wave direction and the full width at half maximum (FWHM) of the absorption spectra for active layer materials are only around 100 nm, which limits the further improvement of PCE. Obviously, ternary PSCs can easily enhance the light-harvesting of the sunlight to promote the charge-generation. Furthermore, the ternary structure can optimize the phase separation of the donor and acceptor materials, and can also improve the driving force for charge transfer and facilitate electron transport in PSCs. Therefore, rational selection of the third component is crucial for the performance of the ternary PSCs. The method of trial and error is still the main approach to find the third component in ternary PSCs, and there is no universal principle guiding for the molecular design of the third component. Actually, the absorption spectra of the double-cabled molecules are the superimposed absorption of the donor backbones and the acceptor pendants with certain blue-shift caused by the enhanced steric hindrance. Benefit from this blue-shift, the double-cable molecule should be the idea third component to construct ternary solar cells with backbone donor and pendant acceptor, and this finding should be the universal design principle for the synthesis of the third component, providing a good idea to further improve the PCE of the PSCs. Herein, we report a novel double-cabled material ITLYBT with the same molecular fragments of donor and acceptor moieties. The absorption spectra of ITLYBT are the superimpose of the donor backbones and the acceptor pendants with nearly 200 nm blue-shift caused by the enhanced steric hindrance, which works as an ideal third component for highly efficient ternary PSCs to broaden and complement the absorption spectra of the photoactive layer. By introducing ITLYBT into PBDB-T-2F:ITIC-4F blend, the ternary device shows enhanced Jsc and Voc, and the over PCE increases from 12.50% to 13.14% due to the optimized phased separation and reduced charge recombination. These results indicate that double-cabled molecule is an ideal third component for construction high performance ternary PSCs.