One-Pot Synthesis and Characterization of Cu-SBA-16 Mesoporous Molecular Sieves as an Excellent Catalyst for Phenol Hydroxylation

The impact of the copper source on the synthesis of meso-structured CuTUD-1: a promising catalyst for phenol hydroxylation

“…27, 33 In addition, very broad peak at above 400 nm is assigned to pseudo-octohedral ligand oxygen 10 environment of copper. 17,18,23,24,33 Among the three samples, CuTA showed an intense absorption peak at 310 nm, which indicate of presence of oligonuclear CuO clusters 18 and also an indirect evidence for lesser incorporation of Cu 2+ into the silica matrix. Furthermore, for all the CuTUD-1 samples a relative 15 percentage of Cu species were estimated from the respective absorption peak areas.…”

“…These results are well in consistent with Cu (II) containing SBA-16 and other copper based materials. 19,23,24 Further the asymmetric peak region could be divided into two 25 peaks, the lower B.E peak at 932.9 eV is assigned to dispersed CuO and higher energy region due to silica connected to Cu 2+ . 23 These observations are in line with DRS UV-Vis and EPR studies.…”

“…19,23,24 Further the asymmetric peak region could be divided into two 25 peaks, the lower B.E peak at 932.9 eV is assigned to dispersed CuO and higher energy region due to silica connected to Cu 2+ . 23 These observations are in line with DRS UV-Vis and EPR studies. From the foregoing characterization results, it can be summarized that a higher amount of isolated Cu (II) species is 30 present in CuTN followed by CuTC and CuTA, whereas a higher concentration of oligonuclear and/or bulk CuO is noticed in CuTA followed by CuTC and CuTN.…”

One-pot Hydrothermal Synthesis of Mesoporous V-SBA-16 with a Function of the pH of the Initial Gel and its Improved Catalytic Performance for Benzene Hydroxylation

“…However, the absence of active sites in the framework of these pure siliceous materials has limited their applications [3]. Many efforts have been devoted to the synthesis of metal-containing SBA-15 and SBA-16 type mesoporous materials by direct synthesis and impregnation methods [4][5][6][7][8][9][10][11]. Nevertheless, it is very difficult to incorporate metal species into the SBA-n silicious framework by direct synthesis due to the difficulties in the formation of metal-O-Si bonds under strongly acidic conditions [8].…”

Liquid phase hydroxylation of benzene to phenol over vanadyl acetylacetonate supported on amine functionalized SBA-15

“…S7). Further increasing the ascorbic acid concentration is not favorable for benzene hydroxylation possibly because the excess ascorbic acid does not directly take part in the reaction and it is [30,40]. On the other hand, excess ascorbic acid might decrease the reactive oxygen species and phenol yield [25,41].…”