Catalytic Graphitization of Cellulose Using Nickel as Catalyst

Microcrystalline cellulose was pyrolyzed and catalytically graphitized under temperatures ranging from 1000 degrees C to 1600 degrees C in the presence of nickel (Ni). Optimal conditions for graphitization were determined, along with the structure and conductivity of the resulting samples. The optimal conditions were identified as heating at 1400 degrees C for 3 h with 3 mmol Ni loading per gram of carbon. The samples obtained had excellent graphitic crystallinity comparable to that of commercial graphite. However, in the absence of Ni loading, no obvious graphitic structure appeared after heating under the same conditions, indicating that Ni was an efficient catalyst for the graphitization of cellulose-based carbon. High-resolution transparent electron microscopy (HRTEM) images showed well-defined graphitic structures of more than 30 layers with slice gaps of 0.340 nm. The conductivities of the samples treated under different temperatures varied from 27 S.cm(-1) to 54 S.cm(-1) under 20 MPa of pressure, and higher temperatures led to higher conductivity due to better graphitic crystallinity. This study fills an important area of research on the catalytic graphitization of cellulose and provides a reference for the preparation of other cellulose-based graphitic materials.