Metal doped graphite phase carbon nitride as a support can effectively improve the catalytic oxidative esterification activity of gold catalyst

The one-step oxidative esterification of aldehydes has become a new choice to replace the traditional ester synthesis process because of its green and efficient advantages. The ester produced by the reaction is a very important chemical raw material, which has high application value and economic value. In this paper, a bimetallic-doped modified graphite phase carbon nitride support MZn-gC 3 N 4 (M = Ce, Co, Mn, Al) was prepared. The Au/MZn-gC 3 N 4 catalyst was prepared by the deposition precipitation method. Then the oxidative esterification activity of benzaldehyde (BAL) was investigated. The introduction of various metals has led to changes in the morphology of the catalysts. The cerium-zinc doped catalyst presented the largest specific surface area. And it presented the best catalytic activity. The conversion of benzaldehyde was as high as 99.9% with a selectivity of 71.3%. The presence of CeO 2 and ZnO was found to affect the electron transfer between Au and g-C 3 N 4 by using techniques such as XPS and in situ DRIFTS. This enhances oxygen activation and reactant adsorption, thus improving catalytic performance. The catalytic performance of the catalysts remained largely unchanged even after reuse for 10 times. The kinetics of the reaction was further investigated and the activation energy of the reaction was obtained as 24.51 kJ/mol.