High response visible-blind organic ultraviolet photodetector based on excellent photovoltaic characteristics of a Cu(I) complex

The phosphorescent Cu(I) complex, [Cu(Bphen)(DPEphos)]BF4 (CuDB) (Bphen = bathophenanthroline, DPEphos = bis[2-(diphenylphosphino) phenyl] ether) has been successfully synthesized and characterised by X-ray single crystal diffraction method. The highly efficient visible-blind ultraviolet organic photodetectors with a peak photoresponse of 316 mA/W using m-MTDATA as the electron donor (D) and CuDB as the electron acceptor (A) was demonstrated. Furthermore, by incorporating 1,3,5-tris(N-phenyl-benzimidazol-2-yl) benzene (TPBi) as an exciton blocking layer (EBL) inserted between CuDB and the cathode, the power conversion efficiency (PCE) of photovoltaic (PV) device based on CuDB was substantially improved to 6.73% which showed a 137% increase over that of device without EBL. Photophysics of the OUV-PDs and PV devices involved were discussed in terms of the device performance and structures. (C) 2016 Elsevier B.V. All rights reserved.