Main-chain Polyimidazolium Polymers by One-pot Synthesis and Application as Nitrogen-doped Carbon Precursors

TL;DR

This study introduces a one-pot synthesis method for main-chain imidazolium polymers with high thermal stability, suitable as nitrogen-doped carbon precursors, demonstrating efficient synthesis, anion exchange, and high carbonization yields.

Contribution

Developed a novel, efficient one-pot synthesis of main-chain imidazolium polymers with high thermal stability and high carbonization yield for use as nitrogen-doped carbon materials.

Findings

High thermal stability of synthesized polymers.

Successful anion exchange with dicyanamide.

Carbonization yield up to 66 wt% at 900°C.

Abstract

This paper reports on the one-pot synthesis of main-chain imidazolium-containing polymers, some of which show unusually high thermal stability. The imidazolium polymers were obtained by modified Debus-Radziszewski reactions for the chain build-up from simple organic compounds, here pyruvaldehyde, formaldehyde, acetic acid, and a variety of diamines. The reactions were performed in aqueous media at ambient conditions, being synthetically elegant, convenient and highly efficient. Finally, a simple anion-metathesis reaction was conducted to replace the acetate anion with dicyanamide, and the thermal properties of the main-chain polyimidazoliums before and after anion exchange were studied in detail, which demonstrated chain cross-linking by the counterion and a coupled unusually high carbonization yield of up to 66 wt% at 900 oC.