Phosphorus- and nitrogen-co-doped particleboard based activated carbon in supercapacitor application

Abstract

Nitrogen-containing activated carbon (AC7525) was prepared by waste particleboards and modified by ammonium biphosphate (PAC7525) for supercapacitor application. The surface areas of AC7525 and PAC7525 are 1204 m² g⁻¹ and 1407 m² g⁻¹, respectively. Galvanostatic charge–discharge curves, cyclic voltammetry and alternating current impedance were employed to investigate the electrochemical properties of the samples. After modification, the element phosphorus was introduced to the surface of the activated carbon cloth. The specific capacitance was improved from 176 to 227 F g⁻¹ under a current density of 50 mA g⁻¹ in a 7 mol L⁻¹ KOH electrolytic solution. The promising electrochemical performances can be attributed to the synergetic effect of (1) pseudocapacitance that originated from rich and tunable surface groups by co-doping of phosphorus and nitrogen; and (2) the electric double layer capacitance that came from the uniform porosities developed by in situ activation.