Chemical Carbonization of Paper Made from Wood Pulp without Thermal Decomposition Using a Catalyst and Structural Properties of the Carbonized Paper

Paper is composed of plant fibers obtained from both wood and non-wood pulp, and the chemical component is mainly cellulose. It is well-known that cellulosic materials are very hard to carbonize at high temperatures because they decompose thermally before forming carbon materials. We have tried chemical carbonization of wood-pulp paper without thermal decomposition using a catalyst to prepare two-dimensional carbon materials. Three kinds of paper (called LBKP-papers here after) made from bleached kraft hardwood pulp having 0.7 similar to 0.76 mm in length weighted mean fiber length and about 260 gm in thickness was used for the chemical carbonization in this work. In the three kinds of LBKP-papers, one includes a wet paper strengthening agent and another one has a little different distribution of the fiber length. One of organic sulfonic acids, methane sulfonic acid (MSA) was used as a catalyst for the carbonization. The LBKP-papers were treated in 1 mol MSA aqueous solution for 5 min and were dried at room temperature. The MSA-treated LBKP-papers were carbonized at 800 degrees C under an Ar gas atmosphere. Structural and physical properties of carbonized LBKP-papers were investigated. All of the LBKP-papers carbonized at 800 degrees C were amorphous and then were crystallized with heat-treatment at higher temperatures, being independent of the wet paper strengthening and the different fiber length distribution. A graphitic structure was developed in carbonized LBKP papers heat-treated at temperatures higher than 2000 degrees C. Mechanical and electrical conductive properties of the carbonized LBKP papers were improved with the heat-treatment.