Effect of co-activation of petroleum coke and Artemisia Hedinii on potassium loss during activation and its promising application in anode material of potassium-ion batteries

The serious potassium loss during the activation process of carbon materials is a troublesome issue that should be highly addressed due to its unfavorable affect to environment and industrialized application. In this study, the co-activation technology was investigated and demonstrated on its positive effect to decrease the potassium release. A co-activated carbon with petroleum coke (PC) and a biomass (Artemisia Hedinii) derived semi-char as raw materials has been prepared. The results show that the combined use of petroleum coke and the biomass semi-char during activation process contributes to 12.73% and 9.42% decrease of potassium loss when compared with that for the individual feedstock activation respectively. Moreover, the co-activation makes larger SSA and total pore volume than the same situation with petroleum coke only. In addition, to increase the added value of active carbon, the feasibility of the co-activated carbon as an anode material of potassium-ion batteries (KIBs) was further explored. The evaluation results of electrochemical performance indicate that the co-activated carbon electrode exhibits excellent long-term cycling stability up to 500 cycles with a capacity retention of 94.5% and good rate capability, implying its promising application in large-scale electrochemical energy storage.