An Amorphous Carbon Nitride Composite Derived from ZIF-8 as Anode Material for Sodium-Ion Batteries

An composite comprising amorphous carbon nitride (ACN) and zinc oxide is derived from ZIF-8 by pyrolysis. The composite is a promising anode material for sodium-ion batteries. The nitrogen content of the ACN composite is as high as 20.4%, and the bonding state of nitrogen is mostly pyridinic, as determined by X-ray photoelectron spectroscopy (XPS). The composite exhibits an excellent Na+ storage performance with a reversible capacity of 430mAhg(-1) and 146mAhg(-1) at current densities of 83mAg(-1) and 8.33Ag(-1), respectively. A specific capacity of 175mAhg(-1) was maintained after 2000 cycles at 1.67Ag(-1), with only 0.016% capacity degradation per cycle. Moreover, an accelerating rate calorimetry (ARC) test demonstrates the excellent thermal stability of the composite, with a low self heating rate and high onset temperature (210 degrees C). These results shows its promise as a candidate material for high-capacity, high-rate anodes for sodium-ion batteries.