| 초록 |
New small molecule (SM) electrolytes based on tosylate anions 2,2’-(ethane-1,2-diylbis(oxy))bis(N,N,N-trimethylethananminium)benzenesulfonate (TEG-M-OTs) and 1,1’-bis(1-dodecyl)-4,40-bipyridine-1,10-diium benzene-sulfonate (V-C12-OTs), were synthesized and applied as a cathode buffer layer to reduce the Schottky barrier in organic solar cells. The efficiencies of the devices based on ZnO with TEG-M-OTs and V-C12-OTs were improved, in which the power conversion efficiencies (PCEs) enhanced from 7.48 % to 7.74 % and 7.88 %, respectively. The PCEs of the devices based on ITO/TEG-M-OTs and ITO/V-C12-OTs were obtained up to 4.22 % and 6.95 %, respectively. The work function (WF) of SM electrolytes with or without ZnO on the ITO surface was measured by the Kelvin probe microscopy. The WFs of SM electrolytes coated ITO are closer to the lowest unoccupied molecular orbitals (LUMO) of the acceptor (- 4.02 eV), compared to the WF of MeOH treated ITO with ZnO (- 4.37 eV). |
