In situ formation of phosphorus-doped porous graphene via laser induction

Abstract

Heteroatom-doped graphene exhibits high energy storage performance when used as an active electrode, and which can been applied to various advanced applications, but challenging in synthesis, e.g., hazardous chemical reagents usage, difficult processing steps, and energy consumption. We demonstrated a ready, rapid and normal method for generating phosphorus-doped graphene (LIPG) using a CO₂ laser on polyimide (PI) substrate mixed with ammonium polyphosphate (APP) in ambient air. LIPG was approved and successfully synthesized via TEM, SEM, XRD and Raman observations. Moreover, we discussed the flame-retardant performance of APP for synthesizing LIPG on PI substrates, increasing the degree of graphitization. Furthermore, LIPG prepared using supercapacitors as an electrode showed good electrochemical performance. Remarkably, the highest specific capacitance of porous LIPG is about 206 F g⁻¹ at the current density of 0.025 A g⁻¹, the value is about 2 times higher than those undoped laser induced graphene (LIG). Such great performance of the LIPG electrode material is attributed to the formation of a hierarchical porous structure, phosphorus atom doping, and manufacturing deficiency. Hence, LIPG showed considerable potential in the electrochemical application field. The proposed preparation of LIPG is best suited for synthesis and applicable to the doping of other heteroatoms doped into graphene.