Two-Dimensional ZincPorphyrin Metal–OrganicFramework Nanosheets for a Self-Powered Organic Photodetector

Abstract

ZnTCPP is one of the widely studied metal–organic frameworks. In optoelectronic devices ZnTCPP finds its applications mostly in solar cells. However, only one report on ZnTCPP (M) films in the photodetector exists. In this work, a 2D zinc porphyrin metal–organic framework (ZnTCPP MOF) is synthesized using the solvothermal method, which exhibits a high specific surface area of 799.43 m² g^–1. The blending of the ZnTCPP MOF nanosheets into the P3HT:PCBM matrix shows broadband self-powered photodetection. The self-powered photodetector is fabricated using the P3HT:ZnTCPP:PCBM blends as an active layer with various (1.0, 0.50, and 0.25) weight ratios of ZnTCPP, and a detailed analysis is performed. Adding ZnTCPP metal–organic framework nanosheets (MONs) to the active layer enhances the overall absorption and lowers carrier recombination. The photodetector with a 0.50 weight ratio of ZnTCPP MONs in the blend gives the best performance parameters among them. For the photodetector with a 0.50 weight ratio, the photosensitivity, responsivity, detectivity, and EQE are observed as ∼10⁴, 0.27 A W^–1, 4.61 × 10¹² Jones, and 64.95%, respectively. Moreover, the on–off measurements show a small rise time and fall time (186.1/83.9 ms). The device retains 80% of its initial value after 3 h of continuous illumination at 520 nm. Thus, the ZnTCPP MONs can be used in self-powered organic photodetectors by modulating their properties for application in image sensing, surveillance, optical communication, health monitoring, and so forth.