Poly(vinyl alcohol)-assisted preparation of melamine resin-derived thick plate-like porous carbon for high-performance all-solid-state supercapacitors

A simple and efficient approach derived from melamine formaldehyde (MF) resin was explored to synthesize porous thick plate-like carbon (TPC) using poly(vinyl alcohol) (PVA) as reagent and dispersant. Ultra-large lateral dimension of over 100–150 μm is achieved with high nitrogen (12.4 at%)/oxygen (10.8 at%) content after MF prolysis at 700°C. The introduction of PVA provides abundant micro and mesopores inside TPC and the folded layered structure increases the specific surface area both of which are beneficial to improve the electrochemical properties of the electrode. The optimized TPC (MTPC-0.2) shows remarkable rate capability as the current densities increased from 0.5 A/g (409.3 F/g) to 20 A/g (330.0 F/g). Further, the all-solid-state supercapacitors built from two identical MTPC-0.2 electrodes delivers dramatically improved volumetric specific capacitance (8.6 F/cm 3 at 1.2 mA/cm 2 ) and volumetric energy density (1.20 at 21.42 mW/cm 3 ) based on the total volume of device.