Improvement in capacitive and Zn-storage performance of asphalt-based N, O, and Mo-doped porous carbon by Mo-catalytic oxidative modification

[Display omitted] With the escalating demand for electrochemical energy storage, asphalt-based porous carbon is emerging as an outstanding candidate for electrodes, which hold a promising outlook in supercapacitors and zinc storage. However, the π-π stacking and conjugation of highly aromatic PAHs in asphalts significantly influence its reaction with activators, rendering it unfavorable for generating reactive groups and defective sites. Thus, the aromaticity of the asphalts has been restricted by catalytic oxidation of MoO3, and the honeycomb N, O, and Mo-doped porous carbon has been acquired by one-step activation with the help of KBr-K2CO3 molten salt. The representative sample, CAC/Mo, possesses a remarkable hierarchical pore structure and abundant heteroatoms. Mo species produce enough defects in the carbon skeleton due to the effect of stress balance and electron arrangement. Consequently, CAC/Mo sustains a high specific capacitance of 432.9F g−1 in the three-electrode system, a high specific capacity of 225.6 mAh/g, and a high energy density of 180.5 Wh kg−1 in the cathode of zinc ion capacitor (ZIC). Next, the composite CAC/Mo@I also attains a satisfactory specific capacity of 161.6 mAh/g and cycling stability in the cathode of a zinc-iodine battery.