| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1440147 | Synthetic Metals | 2016 | 6 Pages |
•Two fluorene-based derivatives, TPF and DFPPO, with wide bandgap were synthesized.•Diphenylphosphine oxide group helps to increase the electron mobility of DFPPO.•TPF and DFPPO can be applied as the acceptor in the active layer of the UV sensor.
Two fluorene derivatives, 2-(1,1′:3′,1″-triphenyl-5′-yl)-9,9-diphenyl-9H-fluorene (TPF) and (9,9-diphenyl-9H-fluoren-2-yl)diphenylphosphine oxide (DFPPO) with wide bandgap and good thermal stability were synthesized. The electron mobility of DFPPO is 5 times higher than that of TPF because of the introduction of the electron-withdrawing diphenylphosphine oxide group. The planar heterojunction organic ultraviolet photodetectors (UVDs) were fabricated by applying TPF or DFPPO as electron acceptor, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) as donor. The UVDs with structure of ITO/PEDOT:PSS/C8-BTBT/DFPPO/LiF/Al presented higher ultraviolet response compared to the TPF based counterpart. Corresponding dark to light current ratio and higher sensitivity is about 179 and 0.69 mA/W under illumination of 1 mW/cm2 365 nm UV light and bias of −0.5 V.
