Design of donors with broad absorption regions and suitable frontier molecular orbitals to match typical acceptors via substitution on oligo(thienylenevinylene) toward solar cells

Abstract

A series of oligo(thienylenevinylene) derivatives with or without thieno[3,2-b]thiophene analogs as cores and three types substituent has been investigated at the PBE0/6-31G(d) and the TD-PBE0/6-31+G(d,p) levels to design materials with high performance such as suitable frontier molecular orbital (FMO) energies to match those of [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) and its derivatives, broad absorption spectra, higher and balance transfer property, and better stability. The results reveal that fused cores have slight effects on photophysical properties of investigated derivatives. The electron-withdrawing or push-pull substituents result in red shifts of absorption spectra and better stabilities for investigated derivatives. The calculated reorganization energies of designed derivatives suggest them to be good potential ambipolar transport materials under the proper operating conditions. The promising donors for PCBM, bisPCBM, PC70BM, and indene-C(60) bisadduct (ICBA) as acceptors are recommended theoretically for solar cells based on the proper match for FMOs between donors and acceptors. Moreover, we have also predicted the mobility of designed molecule with better performance.

Designing Three‐dimensional (3D) Non‐Fullerene Small Molecule Acceptors with Efficient Photovoltaic Parameters

“…Open circuit voltage (V oc ) plays vital role in the performance of organic solar cells . It tells the maximum amount of current which can be drawn from any optical device . V oc is the maximum voltage at zero current level which can be taken from any device.…”

Design of Acceptors with Suitable Frontier Molecular Orbitals to Match Donors via Substitutions on Perylene Diimide for Organic Solar Cells

“…Generally, the higher the lowest unoccupied molecular orbital (LUMO) of the acceptor, the larger the open circuit voltage ( V oc ), because the difference in energy between the highest occupied molecular orbital (HOMO) energy of the donor and LUMO of the acceptor is in direct proportion to the V oc . In addition, to ensure separation of charge, the differences between the LUMO energies of the donor and the acceptor should be greater than 0.30 eV [ 33 ]. Considering the fact that the substituent groups affect the molecular properties significantly, we designed two kinds of molecules ( PDI-BI-1-26 ) to study the push (–CH 3 ) and pull (–CN and –NO 2 ) substituent groups effects.…”

Designing Benzodithiophene‐Based Donor Materials with Favorable Photovoltaic Parameters for Bulk Heterojunction Organic Solar Cells

“…On the basis of open circuit voltage (Voc) we can analyze the performance of the solar cell . It is actually an amount of maximum taken out voltage from any device . Voc is the amount of maximum voltage that is available from particular solar cell at a zero current level.…”