Development of 1D‐Metalloid‐Induced Highly Porous Carbon Nanofiber Conjugated with PEDOT Polymer Through Concurrent Selenization of ZIF‐67 for Energy Storage and Green H 2 Production

Manufacturing high-performance and cost-affordable non-metallic, electroactive 1D carbon material for energy storage and hydrogen evolution reaction (HER) is of foremost importance to respond positively to the impending energy crisis. Porous N-doped carbon nanofiber (PNCNF) is successfully synthesized by electrospinning, using selenium nanoparticles as a sacrificial template (where Se is reutilized for ZIF-67 selenization as a bi-process, and the surface of PNCNF is modified with poly(3,4-ethylenedioxythiophene) (PNCNT/PEDOT) by electropolymerization. The prepared materials are found ideal for energy storage (supercapacitor) and electrocatalysis (HER). The bi-functional material has shown excellent energy storage capability with the specific capacitance (C_S) of 230 F g^-1 (PNCNF) and 395 F g^-1 (PNCNF/PEDOT), and the symmetric supercapacitor device, PNCNF/PEDOT//PEDOT/PNCNF, exhibits 32.4 Wh kg^-1 energy density at 14400 W kg^-1 power density with 96.6% Coulombic efficiency and 106% C_S at the end of 5000 charge-discharge cycles. The rate capability of the symmetric supercapacitor cell of PNCNF/PEDOT is 51% for the current density increase from 1 to 8 A g^-1, while that of PNCNF is a meager 29% only. Electrocatalytic HER at the PNCNF electrode is achieved with an overpotential of 281 mV@10 mA cm^-2 relative to the Pt/C electrode and a low Tafel slop value of 96 mV dec^-1.