Synthesis and ORR performance of nitrogen-doped ordered microporous carbon by CVD of acetonitrile vapor using silanized zeolite as template

摘要

A simple one-step CVD of acetonitrile vapor was successfully used to prepare nitrogen-doped ordered microporous carbon, where zeolite template was silanized to improve activity of carbon deposition into pore walls of the zeolite, CVD time was used to adjust microstructure and nitrogen containing species. XRD, N-2 adsorption isotherms, SEM, TEM and XPS were used to characterize the composition, microstructure, specific surface area (SSA)/pore distribution and chemical state of nitrogen-doped zeolite-templated carbons (N-ZTCs). Electrochemical tests were carried out to analyze the performance of samples as ORR catalyst. The results show that the N-ZTC as prepared at 750 degrees C with CVD time of 4 h (N-ZTC-4h) owns ordered micropores, large SSA and abundant nitrogen containing functional groups. As metal free catalyst, N-ZTC-4h exhibits high current density of ORR, good durability and excellent methanol tolerance. Good catalytic ORR performance of N-ZTC-4h is owed to a large quantity of nitrogen containing species with a high ratio of pyridinic-N and quaternary-N owning activity of ORR and the ordered microporous distribution in three-dimensions for mass transport. Easy preparation process and control method of pore structure and nitrogen containing species of N-ZTCs makes it have a big potential in developing nitrogen doped carbon based catalysts of ORR.