Construction of Fe- and N-Doped Microporous Carbon from Ferrocene-Based Conjugated Microporous Polymers for Supercapacitive Energy Storage

Abstract

The rising interest in conjugated microporous polymers (CMPs) as prospective electrode materials for supercapacitors (SCs) has been dampened by numerous obstacles. Many CMPs exhibit poor conductivity and substandard electrochemical properties, limiting their practical applications. In response to these issues, we successfully synthesized Fe- and N-doped microporous carbon-based materials from Py-BZFC-CMP and Py-PHFC-CMP through calcination and potassium hydroxide (KOH) activation at 800 °C. The resulting microporous carbons, designated as Py-BZFC-CMP-800 and Py-PHFC-CMP-800, demonstrated excellent attributes, including outstanding thermal stability with a Td10 up to 732 °C, and impressive char yields reaching 87 wt %. Furthermore, these materials exhibited large surface areas, peaking at 376 m2 g–1, and a significant total pore volume (PVtotal) of up to 0.36 cm3 g–1. One remarkable material, Py-PHFC-CMP-800, produced through calcination and KOH activation at 800 °C, demonstrated exceptional electrochemical performance. It achieved a specific capacitance of 324 F g–1 at 0.5 A g–1, rivaling some of the highest performing porous carbon materials reported to date. The Py-PHFC-CMP-800 demonstrated outstanding cycling stability, retaining 86% of its capacitance after 5000 charge–discharge cycles at 10 A g–1. This project offers a significant advancement in the field of CMP-based materials by showcasing how rational precursor design and pyrolysis can lead to the creation of high-performance microporous carbons. The Fe and heteroatom doping approach enhances their functionality and opens up possibilities owing to their use in a valuable application, including efficient energy storage systems.