In Situ Growth of Highly Porous Zeolitic‐Imidazolate Frameworks‐8 on Copolymer Derived Carbon for High‐Performance Supercapacitor

A zeolitic-imidazolate frameworks (ZIF-8)/copolymer-derived carbon composite is synthesized via in situ growth of porous ZIF-8 on conducting carbon, combining high surface area with efficient charge transport. The electrode achieves 25.7 Wh kg⁻¹ of energy density, and 92.9% retention after 10 000 cycles, demonstrating its potential for durable aqueous supercapacitors.

Zeolitic-imidazolate frameworks (ZIFs) are gaining widespread attention in energy storage research owing to their high porosity, structure tailorability, and multiple reaction sites. However, their very low inherent electrical conductivity limits their pristine usage in supercapacitors. Therefore, a promising way is to integrate ZIFs with suitable conductive materials, which can help to provide additional conductive pathways, thereby promoting fast charge transfer. In this work, a strategy is proposed to improve the conductivity of ZIF-8 by incorporating it with PANI-PPy conducting copolymer-derived carbon (CoP@C). The prepared ZIF-8/CoP@C composite possesses nitrogen units (pyridinic-N, graphitic-N, and pyrrolic-N) that enhance its electronic conductivity and provide additional pseudo-capacitance. In a three-electrode setup with 1 M H₂SO₄ electrolyte, the ZIF-8/CoP@C composite electrode demonstrated the highest specific capacitance of 247.9 F g⁻¹, which is much higher than the pristine ZIF-8 electrode (72.1 F g⁻¹) at 1 A g⁻¹. Furthermore, the ZIF-8/CoP@C electrodes were employed to construct an aqueous symmetrical supercapacitor that delivers a high energy density of 25.7 Wh kg⁻¹ and a power density of 402.1 W kg⁻¹, along with prolonged cyclic stability of 92.9% after 10 000 charge–discharge cycles. This study introduces a benchmark for employing conducting copolymers to elevate the electrochemical performance of different ZIFs/MOFs in supercapacitors.

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