Directly Fabricated Flexible Photodetector Based on TiO₂-Doped Carbon Nanosheets Film

Abstract

Flexible photodetector is crucial for the intelligent industrial applications. However, the optical-sensitive materials are usually grown in a high temperature and then transferred onto the flexible substrate. This paper reported a directly fabricated flexible photodetector based on TiO2-doped Graphene Nanosheets Embedded Carbon (GNEC)film. An Electron Cyclotron Resonance (ECR) system was employed to in-situ deposit TiO2-doped GNEC film on a polyimide substrate, which were subsequently sensitized with N719 dye to fabricate the TiO2@GNEC photodetector. The GNEC film contains vertically aligned Graphene Nanosheets (GNs), which exhibit high-density edge states. The edge states suppress the recombination rate of photo-generated electron-hole pairs, thereby significantly enhancing the photo-responsive performance. The photodetector demonstrates a high photo responsivity of 0.82 mA/W and a response time of 1.93 seconds. Due to the in-situ manufacturing capabilities of the ECR system, which avoids defects from secondary material transfers, the photodetector array exhibits excellent consistency and achieves clear recognition of light patterns in both flat and bent states.