Chemically Stable Polyarylether-Based Metallophthalocyanine Frameworks with High Carrier Mobilities for Capacitive Energy Storage

Covalent organic frameworks (COFs) with efficient charge transport and exceptional chemical stability are emerging as an import class of semiconducting materials for opto-/electronic devices and energy-related applications. However, the limited synthetic chemistry to access such materials and the lack of mechanistic understanding of carrier mobility greatly hinder their practical applications. Herein, we report the synthesis of three chemically stable polyarylether-based metallophthalocyanine COFs (PAE-PcM, M = Cu, Ni, and Co) and facile in situ growth of their thin films on various substrates (i.e., SiO2/Si, ITO, quartz) under solvothermal conditions. We show that PAE-PcM COFs thin films with van der Waals layered structures exhibit p-type semiconducting properties with the intrinsic mobility up to similar to 19.4 cm(2) V-1 s(-1) and 4 orders of magnitude of increase in conductivity for PAE-PcCu film (0.2 S m(-1)) after iodine doping. Density functional theory calculations reveal that the carrier transport in the framework is anisotropic, with the out-of-plane hole transport along columnar stacked phthalocyanine more favorable. Furthermore, PAE-PcCo shows the redox behavior maximumly contributes similar to 88.5% of its capacitance performance, giving rise to a high surface area normalized capacitance of similar to 19 mu F cm(-2). Overall, this work not only offers fundamental understandings of electronic properties of polyarylether-based 2D COFs but also paves the way for their energy-related applications.

Automated summary

This study reports the synthesis of COFs with efficient charge transport and chemical stability, as well as the growth of thin films on various substrates. The thin films exhibit excellent semiconducting properties and significant increases in conductivity. Additionally, density functional theory calculations reveal the anisotropic nature of carrier transport in the framework.