3D g-C3N4/Mn3O4 heterostructures towards high energy density supercapacitor

Graphic carbon nitride (g-C 3 N 4 ) as a typical photocatalyst has large specific surface area and high stability. However, the application for supercapacitors is limited because of its poor electrical conductivity. In this paper, three-dimensional (3D) g-C 3 N 4 /Mn 3 O 4 heterostructures with enhanced supercapacitor properties were constructed by a two-step synthesis. The precursor of 3Dg-C 3 N 4 /Mn 3 O 4 was firstly prepared by a freeze-drying process using NaCl as templates. After thermal polymerization at high temperature and subsequent removal of NaCl, 3D g-C 3 N 4 /Mn 3 O 4 heterostructures were constructed. As prepared samples revealed high specific capacitance performance which is related the well dispersion of Mn 3 O 4 in 3D g-C 3 N 4 networks to expose more redox catalytic centers. The result indicated with a current density of 1 A/g, the specific capacitance of sample prepared using optimized conditions was 753.9 F g −1 which is much higher than that of other samples. The stability test indicates the sample revealed high stability (84.1 %) after 5000 cycles under 5 A/g because of excellent structural stability of g-C 3 N 4 . The result provides a useful strategy for the application of g-C 3 N 4 in energy storage.