One-pot synthesis of heteroatom-rich anthraquinone-based benzoxazine-linked porous organic polymers for high performance supercapacitors

Recently, the search for efficient and durable electrodes for energy storage has prompted the development of novel porous organic polymers (POPs). Here, we have studied the design, preparation and comprehensive characterization of a novel set of anthraquinone-based benzoxazine-linked POPs as electrode materials for supercapacitors (SCs). The polymers with high yield have been synthesized by direct coupling of various triamines, diphenol and paraformaldehyde. The benzoxazine linkage´s formation and porosity parameters were readily analyzed using FTIR spectra, solid-state ¹³C NMR and N₂ sorption analysis. The benzoxazine backbone provides the POPs with abundant nitrogen and oxygen heteroatoms, making them efficient candidates for storing energy. We observed that the superior benzoxazine-linked polymer exhibited the greatest electrochemical capacitance up to 117.7 F g^‒1 at 1.0 A g^‒1 was the An-TPA POP, which was mainly owing to the best microporous structure, accessible morphology and the largest specific surface area compared to others. In addition, it possessed the highest retention stability after 10,000 charge-discharge cycles (81.55 %), as well as lower ohmic resistance (5.38 Ω). Interestingly, a two-electrode system holding the An-TPA POP displayed an excellent electrochemical capacitance of 62 F g⁻¹ at 1.0 A g⁻¹, a greater cycling retention of 95.71 % after 5000 GCD cycles at 10 A g⁻¹, as well as a prime energy density of 8.57 W h kg^–1. The results obtained demonstrated a significant tactic for constructing heteroatoms-rich POPs for next-generation SCs, offering improved efficiency and stability.