Enhanced activation of persulfate improves the selective oxidation of alcohols catalyzed by earth-abundant metal oxides embedded on porous N-doped carbon derived from chitosan

Abstract

The selective oxidation of alcohols aiming at the formation of aldehydes and esters is an essential reaction for the fine chemical industry. However, the classical processes to obtain aldehydes present...

Cerium Oxide Nanoparticles Confined in Doped Mesoporous Carbons: A Strategy to Produce Catalysts for Imine Synthesis

“…The high-resolution N 1s spectrum of CN-meso (Figure C) shows four peaks related to N pyridinic at 398.2 eV (39%), N pyrrolic at 400.6 eV (45%), N graphitic at 402.8 eV (11%), and N oxide at 405 eV (5%). , The major N-species on the carbon frame is N pyrrolic , which is an N species bonded with two carbon in a five-sided ring; they are commonly located on the edges or vacancies of graphitic carbon. Following the Lewis hard–soft interaction principle, N pyrrolic presents an electron-donor nature (Lewis base) and high charge mobility. , N pyrrolic can also act as a link point between the carbon structure and metal species. , …”

“…Two extra peaks are located at 1146 cm −1 , which are related to the elongation of P�O/P− O−C/HO−P�O bonds or O−H bending of carboxyl and 872 cm −1 groups and bending of C�C bonds. 58,62,67 The TG analyses (Figure S2) show that the materials are thermally stable until 350 °C, and a big mass loss takes place around 420−600 °C and a further mass loss at 800 °C, confirming the complete removal of the silica template.…”

“…Following the Lewis hard−soft interaction principle, N pyrrolic presents an electron-donor nature (Lewis base) and high charge mobility. 50,62 N pyrrolic can also act as a link point between the carbon structure and metal species. 63,64 The Raman spectra of the synthesized carbon (Figure 3A) exhibit two typical peaks at 1332 cm −1 and 1597 cm −1 , which correspond to the D-band (defective structure) and G-band (graphitic sites), respectively.…”

Sonocatalytic Activity of Porous Carbonaceous Materials for the Selective Oxidation of 4-Hydroxy-3,5-dimethoxybenzyl Alcohol

“…CN-meso Chit: This material was synthesized using a previously developed methodology [18]. In summary, acetic acid (4 mL) was added to 100 mL of water; then, 2 g of chitosan was added.…”

“…Researchers have been exploring the application of heterogeneous catalysis in selective oxidation reactions to provide a more environmentally friendly alternative to traditional reactions using toxic chemical oxidants. Many strategies, such as thermal, photo, or sonocatalysis, have been reported [8][9][10][11][12][13][14][15][16][17][18].…”