Improvement photoresponsivity and quantum efficiency of photodetector sensitized by organic dye

In this paper, Four dye-sensitive photodetectors were prepared, with three layers. The first was a photoanode layer represented by titanium dioxide deposited using pulsed laser ablation (PLA) on the surface of fluoride tin oxide (FTO) glass; the second layer, is a photosensitive dye, which was represented by the organic dye Rhodamine, and the third layer, which is represented by the photocathode layer, which is represented by platinum deposited on the surface of the FTO Glass using DC sputtering technique. An electrolytic solution is placed between the layers. Platinum layer applied to the surface of a fluoride tin oxide glass, and a photoanode layer doped With graphene at concentrations of 1%, 3%, and 5%. The structural characteristics (current-Voltage characteristics, X-ray diffraction) were examined for the prepared photodetectors. The X-ray diffraction results demonstrated the polycrystalline structure of the produced films. The Voltage between − 5 and 5 volts was the optimal current in the dark, (0.04 mA). The best external Quantum efficiency (16%) at photoanode doped with 5% of graphene. Experiments have demonstrated that an increase in concentrations of graphene leads to an increase in Photoresponsivity, quantum efficiency, and absorbance.