Low-Cost Perovskite Solar Cell Based on Imidazole Hole Transport

Hole transport materials (HTMs) are one of the most important components in perovskite solar cell (PSC) which their presence play as a key factor to achieve the high efficiency of conversion of solar irradiation to electricity. That is why the searching of new efficient and cost-effective HTMs for using in PSC is one of the hottest research objects in PSC filed. In this paper, a new generation of a bi-nuclear organic HTM for using in PSC has been prepared and introduced. Bi-nuclear organic-HTM bis(4-(4,5-diphenyl-2-(p-tolyl)-4,5-dihydro-1H-imidazol-1-yl)phenyl)methane, namely MDA-PI2 , based on benzyl imidazoles was synthesized and fully characterized and finally was applied as a bi-nuclear organic HTMs in PSC. Since the photophysical, photochemical and electrochemical properties of HTMs play key role in a PSC, a variety of analysis and measurements including cyclic voltammetry, thermal stability, photoluminescence and water contact angle were carried out which indicated the promising performance of newly synthesized HTM in a PSC. In addition, the luminescence quenching value of novel HTM was very close to bench-mark Spiro-OMeTAD in the presence of perovskite absorber layer which proved the efficient transferring of holes in PSC. After fabrication of perovskite solar cell without any HTM and with it, the efficiency of PSC was dramatically increased from 1.57 % to 6.60 % , respectively which shown the good performance of HTMs based on imidazole rings.