Graphite Whiskers Derived from Waste Coffee Grounds Treated at High Temperature

Graphite whiskers (GWs) are obtained from coffee grounds (CGs) treated at 2500 degrees C for 1 h in the presence of Ar gas at 1 atm. The majority of the GWs formed inside the CGs shell are rod-like with a conical tip with diameter and length in the range between 1 to 3 mu m and 4 to 10 mu m, respectively. At first, the carbon layer might be grown in a turbostratic manner, and then progressively graphitized at higher temperature. The strong G ' peak intensity might be induced by the disclination of graphitized carbon layers.