ERB-1 zeolite emerges as a key bridging material for crafting heteroatom-containing MWW for versatile catalytic applications.In this study,we developed a solvent-free strategy facilitated by high-temperature condition...ERB-1 zeolite emerges as a key bridging material for crafting heteroatom-containing MWW for versatile catalytic applications.In this study,we developed a solvent-free strategy facilitated by high-temperature condition and seed assistance,streamlining the synthesis of ERB-1 zeolite.This novel approach not only significantly reduces the growth time to 12 h compared to the conventional 168-h hydrothermal synthesis but also enhances product yield while minimizing waste generation.Benefiting from the platelet seeds and the grinding force,a distinct non-classical growth pathway,involving nanoparticle attachment,epitaxial growth,anisotropic assembly,and crystallization,was observed in the solvent-free synthesis.Through heteroatom substitution,pillared Sn-MWW was successfully prepared,exhibiting remarkable stability and catalytic performance in the Bayer-Villiger oxidation reaction of 2-adamantanone.Our findings present a simple and cost-effective way for rapid synthesis of MWW zeolite,with implications extending to diverse catalytic applications.展开更多
The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic...The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic CD bands of GDL and its hydrolysis product, the dynamics of hydrolysis was studied using stopped-flow CD method. Using chiral Raman spectroscopy (CRS), the stereochemical change of GDL owing to the hydrolysis reaction was discussed on the vibrational scale. The CRS results show that the ring-opening due to hydrolysis has a great influence on the chiral structure around the car-bonyl group, which was evidenced by the disappearance of the CRS band at 1735 cm-1 (C== O stretching vibrational mode). In addition, the change of positions and intensity of CRS bands was also observed, which was ascribed to the perturbation around the C2, C3, C4 and C5 carbons due to ring-opening. It is worthy to note that the stereochemistry of C2, C3, C4 and C5 had no fundamental change during the hydrolysis reaction, which was reflected in the maintenance of the signs of the CRS bands. Our results demonstrate that in comparison with CD technique, CRS may provide more detailed structural information of chiral molecules and open up new vistas of research for chiral reactions.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22002012,22372020)the Fund of the State Key Laboratory of Catalysis in DICP,China(No.N-21-02).
文摘ERB-1 zeolite emerges as a key bridging material for crafting heteroatom-containing MWW for versatile catalytic applications.In this study,we developed a solvent-free strategy facilitated by high-temperature condition and seed assistance,streamlining the synthesis of ERB-1 zeolite.This novel approach not only significantly reduces the growth time to 12 h compared to the conventional 168-h hydrothermal synthesis but also enhances product yield while minimizing waste generation.Benefiting from the platelet seeds and the grinding force,a distinct non-classical growth pathway,involving nanoparticle attachment,epitaxial growth,anisotropic assembly,and crystallization,was observed in the solvent-free synthesis.Through heteroatom substitution,pillared Sn-MWW was successfully prepared,exhibiting remarkable stability and catalytic performance in the Bayer-Villiger oxidation reaction of 2-adamantanone.Our findings present a simple and cost-effective way for rapid synthesis of MWW zeolite,with implications extending to diverse catalytic applications.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20621063, 20773123, and 20673110)Programme for Strategic Scientific Alli-ances between China and the Netherlands (Grant No. 2008DFB50130)
文摘The alkali-hydrolysis of D-glucono-delta-lactone (GDL) was investigated by chiral Raman and circular dichroism (CD) spectroscopies in combination with density functional theory calculation. Based on the characteristic CD bands of GDL and its hydrolysis product, the dynamics of hydrolysis was studied using stopped-flow CD method. Using chiral Raman spectroscopy (CRS), the stereochemical change of GDL owing to the hydrolysis reaction was discussed on the vibrational scale. The CRS results show that the ring-opening due to hydrolysis has a great influence on the chiral structure around the car-bonyl group, which was evidenced by the disappearance of the CRS band at 1735 cm-1 (C== O stretching vibrational mode). In addition, the change of positions and intensity of CRS bands was also observed, which was ascribed to the perturbation around the C2, C3, C4 and C5 carbons due to ring-opening. It is worthy to note that the stereochemistry of C2, C3, C4 and C5 had no fundamental change during the hydrolysis reaction, which was reflected in the maintenance of the signs of the CRS bands. Our results demonstrate that in comparison with CD technique, CRS may provide more detailed structural information of chiral molecules and open up new vistas of research for chiral reactions.
