Efficiency Enhancement of P3HT: PCBM Based Organic Photovoltaic Devices via Incorporation of Bio-synthesized Gold Nanoparticles

Bio-synthesized gold nanoparticles (AuNPs) with bacteria have been used to enhance the efficiency of P3HT: PCBM based Organic Photovoltaic (OPV) devices. First, AuNPs were synthesized in Bacillus Subtilis containing medium and characterized by zeta potential analyzer, energy dispersive X-ray spectrometer (EDS), UV-Vis spectrometer and Transmission Electron Microscope (TEM). The shape of AuNPs was found to be mainly spherical with an average diameter of 8.01 nm bearing negative surface charge (pH: 2~11). Next, the AuNPs were added to the PEDOT: PSS solution and spin-coated on the ITO substrate, followed by coating the active layer (P3HT:PCBM) and deposition of the metal electrodes. It has been observed that the power conversion efficiency (PCE) increased from 2.98 to 3.39% (enhancement of 14%) at optimum conditions by incorporation of bio-synthesized AuNPs in the whole transport layer.