Tuning the optoelectronic properties of Benzo Thiophene (BT-CIC) based non-fullerene acceptor organic solar cell

Organic solar cells have become a center of attention in the field of research and technology due to its remarkable features. In the current research work, we designed Benzo Thiophene (BT-CIC) based non-fullerene acceptor organic solar cell having A-D-A novel structure. The designed structures D1-D4 were derived from BT-CIC (non-fullerene acceptor) by replacing 2-(5,6-dichloro-2-methylene-3-oxo-2,3-dihydro-1H-inden-1-ylidene)acetonitrile of reference molecule R with different electron withdrawing end-capper acceptor moieties. The effect of end acceptor groups on absorption, energy level, charge transport, morphology, and photovoltaic properties of the designed molecules (D1-D4) were investigated by TD-DFT B3LYP/6-31G basic level of theory and compared with reference molecule R. Among all novel structures, D3 exhibited maximum absorption (lambda(max)) of 701.7nm and 755.2nm in gaseous state anfd chloroform, respectively. The red shift in D3 was due to the presence of strong electron withdrawing acceptor moiety and more extended conjugation as compared to other structures. D3 also displayed lowest values of energy bandgap (1.97 eV), lambda(e) (0.0063 eV) and lambda(h) (0.0099 eV) and which signify its ease electron mobility. Lowest value of binding energy 1.20 eV of D3 suggested that this molecule could be easily dissociated into charge carriers TDM results revealed that easy exciton dissociation occurred in D3. Overall, designed structure D3 was found to be more effective and efficient acceptor molecule for SMOSCs. The findings provide novel information for the development of non-fullerene acceptors for OPVs.