Novel Zinc-porphyrin dyes for dye-sensitized solar cells that enables light capture in the near-ultraviolet and visible range

Abstract

Two novel Zinc-porphyrin central dyes (T-5 and T-6) containing acetylene moiety have been designed and synthesized for application in dye-sensitized solar cells (DSSCs). The light-harvesting capabilities and photovoltaic performance of these dyes were investigated systematically through comparison of different donor (D) unit. Devices fabricated from phenoxazine (POZ)-based molecule T-5 showed higher short-circuit current (JSC, 11.32 mA cm-2) compared to T-6 which based on phenothiazine (PTZ) (10.1 mA cm-2) under standard global AM 1.5 G solar condition. This is due to the fact that the POZ unit has a greater electron supply capacity than the PTZ unit. The introduction of the acetylene moieties into the molecular structure broadens the light absorption range of the dye molecule to the entire visible range and the near-ultraviolet region. The conclusions of this paper demonstrate that incorporating strong electron donor groups in dye molecules, in synergy with conjugated groups, broadens the spectral range of light absorption, thereby enhancing the performance of the dye device.