The obtained ZIF-8 was soaked in furfuryl alcohol and stirred for 24 h, followed by filtration.
The solid was washed with methanol to remove the furfuryl alcohol adhesive to the outer surface of the ZIF-8.
Subsequently, the furfuryl alcohol/ZIF-8 composite was transferred into a quartz boat.
After removing the air with a gentle flow of N2 gas for 8 h, the furfuryl alcohol which was accommodated in the pores of ZIF-8 was polymerized by heating at 80 °C for 24 h and then 150 °C for 6 h under a N2 flow.
Finally, the carbonization of the product was performed at 900 °C in a N2 flow for 8 h to get the ZIF-8-NPC.