Photovoltaic characteristics of single wall carbon nanotube (CNT): PCBM organic solar cell-effect of CNT chirality variation

This paper advances the field of single wall carbon nanotube (SWCNT) organic solar cells by studying the photovoltaic characteristics to understand the optimization process for obtaining better power conversion efficiency (PCE). Open circuit voltage (Voc) is interpreted with the energy offset between donor and acceptor level. Quantum efficiency (QE) has been simulated considering absorption, exciton dissociation and charge collection efficiency for OPV materials. The simulated QE summed over the solar spectrum to find the short circuit current density (Jsc). Single chiral semiconducting single wall carbon nanotube (s-SWCNTs) are used as the donor with (6,6)-phenyl-C61- butyric acid methyl ester (PCBM). By changing the chirality of SWCNTs, the photovoltaic parameters are optimized. Highest Voc of 0.7849V has been achieved for (8,1) chiral CNT. Jsc can be maximized up to 3.65mA/cm2 and fill factor to 0.466 for (10,3) CNT. Finally PCE of around 1% has been found for chirality (10,3) and (11,1). In this work PCE has been increased through a range of about 14.75% by changing the chirality of CNTs.