Polyurethane and polyaniline foam-derived nickel oxide-incorporated porous carbon composite for high-performance supercapacitors

A new type of polyurethane and polyaniline foam-derived nickel oxide-incorporated porous carbon composite (PPFPC-NiO) was synthesized through a combination of in situ polymerization, chemical blowing and carbonization methods and was studied for the first time. By taking advantage of a polyaniline-introduced polyurethane foam as a porous carbon skeleton precursor, interconnected nickel oxide-incorporated nanowires provided hierarchical porous conductive network structures after carbonization treatment, forming stable three-dimensional coralline-like open nano-architectures, which not only enhance the electrical conductivity and accelerate the electron transport rate during the charge-discharge process but also provide myriads of open hierarchical porous channels for rapid ion diffusion, increasing the number of available reactive sites in the PPFPC-NiO. As an electrode in supercapacitors, the PPFPC-NiO exhibits a high specific capacitance of 1012.8 F g(-1) at 1 A g(-1), with a capacitance retention of 96.43% after 5000 cycles in a three-electrode test and with 6 M KOH as the electrolyte. Because of these properties, an asymmetric supercapacitor is assembled using the PPFPC-NiO as the positive electrode and a mixture of activated carbon and graphite as the negative electrode. In a potential window of 1.5 V, the capacitor exhibits a high energy density of 32.2 Wh kg(-1) at a power density of 281.3 W kg(-1), which remains at 22.5 Wh kg(-1), even at a high-power density of 1472.7 W kg(-1). More importantly, the capacitor also shows excellent cycling stability, with 92.71% capacitance retention after 5000 cycles.