South China University of Technology

About: South China University of Technology is a education organization based out in Guangzhou, China. It is known for research contribution in the topics: Catalysis & Adsorption. The organization has 62343 authors who have published 69468 publications receiving 1251592 citations. The organization is also known as: SCUT & Huánán Lǐgōng Dàxué.

Packaging and delivering enzymes by amorphous metal-organic frameworks.

Abstract: Enzymatic catalysis in living cells enables the in-situ detection of cellular metabolites in single cells, which could contribute to early diagnosis of diseases. In this study, enzyme is packaged in amorphous metal-organic frameworks (MOFs) via a one-pot co-precipitation process under ambient conditions, exhibiting 5–20 times higher apparent activity than when the enzyme is encapsulated in corresponding crystalline MOFs. Molecular simulation and cryo-electron tomography (Cryo-ET) combined with other techniques demonstrate that the mesopores generated in this disordered and fuzzy structure endow the packaged enzyme with high enzyme activity. The highly active glucose oxidase delivered by the amorphous MOF nanoparticles allows the noninvasive and facile measurement of glucose in single living cells, which can be used to distinguish between cancerous and normal cells. For packaging enzymes into metal–organic frameworks (MOFs), crystalline MOFs are usually used. Here, the authors encapsulated enzymes in amorphous MOFs a via one-pot co-precipitation process under ambient condition, which led to higher enzymatic activity than in a corresponding crystalline MOF composite.

Ultra-Tuning of the Aperture Size in Stiffened ZIF-8_Cm Frameworks with Mixed-Linker Strategy for Enhanced CO2 /CH4 Separation.

Abstract: ZIF-8 membrane has the potential for CO2 /CH4 separation based on size exclusion. But if traditionally prepared by solvothermal methods, it shows only negligible selectivity due to the linker mobility. Here, ≈500 nm-thin hybrid ZIF-7x -8 membranes with suppressed linker mobility and narrowed window aperture are prepared by a fast current-driven synthesis (FCDS) within 20 min. The in situ electric field during FCDS allows the formation of stiffened ZIF-8_Cm as parent skeleton and the mixed-linker strategy is applied to narrow the aperture size simultaneously. The ZIF-722 -8 membrane shows significantly sharpened molecular sieving for CO2 /CH4 with a separation factor above 25, which soared tenfold compared with other unmodified ZIF-8 membranes. Additionally, the membrane shows exceptional separation performance for H2 /CH4 and CO2 /N2 , with separation factors of 71 and 20, respectively. After 180 h temperature swing operation, it still maintains the excellent separation performance.

Catalytic transfer hydrogenation of butyl levulinate to γ-valerolactone over zirconium phosphates with adjustable Lewis and Brønsted acid sites

Abstract: The efficient production of γ-valerolactone (GVL) from renewable resources is attracting increasing attention in view of its wide application in fuel and synthetic chemistry. In this study, a series of novel and efficient zirconium phosphate catalysts were developed for the transfer hydrogenation of levulinate esters to GVL using isopropanol as the hydrogen donor. Experimental results show that 98.1% butyl levulinate conversion and 95.7% GVL yield can be achieved with ZrPO-1.00 at 483 K after 2.0 h. Intensive characterization of the synthesized catalysts using N 2 adsorption-desorption, FT-IR, ICP-AES, XPS, NH 3 -TPD, Py-FTIR and XRD demonstrates that the physicochemical properties, particularly hydrophobicity, Lewis to Bronsted acid site ratio and Lewis acid site strength were subtly tuned via adjustment of the molar proportion of phosphorus to zirconium, which is responsible for excellent transfer hydrogenation activity. Furthermore, this optimized catalyst exhibits high stability and recyclability for at least ten reaction cycles. In addition, a plausible reaction pathway and catalytic mechanism are proposed.