Nitrogen-Doped Porous Carbon Derived from Covalent Triazine Framework for Catalytic Oxidation of Benzyl Alcohol

Nanomaterials (Basel). 2024 Apr 24;14(9):744. doi: 10.3390/nano14090744.

Abstract

The catalytic oxidation of alcohols is an important transformation in the chemical industry. Carbon materials with a large surface area and N doping show great promise as metal-free catalysts for the reaction. In this study, a rich N-containing covalent triazine framework polymerized by cyanuric chloride and p-phenylenediamine was used to synthesize N-doped porous carbon with the assistance of a pore-forming agent-NaCl. First, the mass ratio of the polymer/NaCl was optimized to 1:9. Then, the influence of the pyrolysis temperatures (700-1000 °C) on the materials was studied in detail. It was found that the carbon materials were gradually exfoliated by molten salt at high temperatures. XRD and Raman characterizations showed them with a certain graphitization. The optimal doped carbon CNN-1-9-900 achieved the highest surface area of 199.03 m2g-1 with the largest pore volume of 0.29 cm3g-1. Furthermore, it had a high N content of 9.9 at% with the highest relative proportion of pyridinic/graphitic N. Due to the synergistic effect between the surface area and pyridinic/graphitic N, CNN-1-9-900 showed the best performance for benzyl alcohol oxidation with TBHP at moderate conditions, and the process also worked for its derivatives.

Keywords: N-doped carbon; NaCl; benzyl alcohol oxidation; covalent triazine framework.