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Selective oxidation of methane to organic oxygenates over metal—organic frameworks (MOFs) catalysts at low temperature is a challenging topic in the field of C1 chemistry because of the inferior stability of MOFs. Modifying the surface of Cu-BTC via hydrophobic polydimethylsiloxane (PDMS) at 235 °C under vacuum not only can dramatically improve its catalytic cycle stability in a liquid phase but also generate coordinatively unsaturated Cu(I) sites, which significantly enhances the catalytic activity of Cu-BTC catalyst. The results of spectroscopy characterizations and theoretical calculation proved that the coordinatively unsaturated Cu(I) sites made H₂O₂ dissociative into •OH, which formed Cu(II)-O active species by combining with coordinatively unsaturated Cu(I) sites for activating the C—H bond of methane. The high productivity of C1 oxygenates (CH₃OH and CH₃OOH) of 10.67 mmol gcat. −1h−1 with super high selectivity of 99.6% to C1 oxygenates was achieved over Cu-BTC-P-235 catalyst, and the catalyst possessed excellent reusability.

PtSn catalysts were synthesized by incipient-wetness impregnation using a dendritic mesoporous silica nanoparticle support. The catalysts were characterized by XRD, N2 adsorption–desorption, TEM, XPS and Raman, and their catalytic performance for propane dehydrogenation was tested. The influences of Pt/Sn ratios were investigated. Changing the Pt/Sn ratios influences the interaction between Pt and Sn. The catalyst with a Pt/Sn ratio of 1:2 possesses the highest interaction between Pt and Sn. The best catalytic performance was obtained for the Pt1Sn2/DMSN catalyst with an initial propane conversion of 34.9%. The good catalytic performance of this catalyst is ascribed to the small nanoparticle size of PtSn and the favorable chemical state and dispersion degree of Pt and Sn species.

The preparation of porous materials by the simple and low-cost methods is one of the hot topics in materials science. Here, the porous carbon-incorporated BN (P-CBN) was synthesized from the low-cost flour by a fermentation combined with freeze-drying technology and ammonolysis. P-CBN-x samples not only maintain the pores of the fermented dough, but also produce abundant oxygen-containing boron species (B-OH, O-O and B-O). Due to the unique structural advantages, P-CBN- x catalysts exhibit remarkably better catalytic performance than bulk BN for the oxidative dehydrogenation of propane (ODHP) to produce olefins. Attractively, P-CBN-23 obtains high C 3 H 8 conversion of 62.1% and olefin yield of 42.7%. In-situ DRIFTS experiments and DFT calculations demonstrate the B-OO-B species in P-CBN- x framework is the most active species for the C 3 H 8 activation and the B-O…O-B species can be readily regenerated by O 2 , thus promoting the conversion of propane to olefin.

The selective oxidation of methane under mild conditions remains the “Holy Grail of Catalysis”. The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active centers. Copper nanoparticles were loaded onto TiO 2 nanofibers using the photo-deposition method. The resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild conditions. Compared with previously reported catalysts, it delivers a superior performance of up to 2510.7 mmol·g Cu −1 ·hr −1 productivity with a selectivity of around 100% at 80 °C for 5 min. Microstructure characterizations and density functional theory (DFT) calculations indicate that TiO 2 in the mixed phase of anatase and rutile significantly increases the Cu + /Cu 0 ratio of the supported Cu species, and this ratio is linearly related to the formation rate of oxygen-containing species. The Cu 1 site promotes the generation of active O species from H 2 O 2 dissociation on Cu 2 O (111). These active O species reduce the energy barrier for breaking the C–H bond of CH 4 , thus boosting the catalytic activity. The methane conversion mechanism was proposed as a methyl radical pathway to form CH 3 OH and CH 3 OOH, and then the generated CH 3 OH is further oxidized to HOCH 2 OOH.

The direct oxidation of methane to methanol as a liquid fuel and chemical feedstock is arguably the most desirable methane conversion pathway. Currently, constructing and understanding linear scaling relationships between the fundamental physical or chemical properties of catalysts and their catalytic performance to explore suitable descriptors is crucial for theoretical research on the direct conversion of methane to methanol. In this review, we summarize the energy, electronic, and structural descriptors used to predict catalytic activity. Fundamentally, these descriptors describe the redox properties of active sites from different dimensions. We further explain the moderate principle of descriptors in methane-to-methanol catalyst design and provide related application work. Simultaneously, the underlying activity limitation of methane activation and active species generation is revealed. Based on the selectivity descriptor, the inverse scaling relationship limitation between methane conversion and methanol selectivity is quantitatively understood. Finally, multiscale strategies are proposed to break the limitation and achieve the simultaneous enhancement of activity and selectivity. This descriptor-based review provides theoretical insights and guidance to accelerate the understanding, optimization, and design of efficient catalysts for direct methane-to-methanol conversion.

The development of an effective strategy for synthesizing two-dimensional MFI zeolites has attracted more and more attention. Herein, nanosheet-stacked hierarchical ZSM-5 zeolite was obtained by a seed-assisted hydrothermal synthesis route using a small amount of [C18H37-N+(CH3)2-C6H12-N+(CH3)2-C6H12]Br2 (C18-6-6Br2) as a zeolite structure-directing agent and triethylamine (TEA) as a zeolite growth modifier. By varying the molar ratio of C18-6-6Br2/TEA from 2.5/0 to 2.5/40, the morphologies and textural properties of the resultant HZ5-2.5/x catalysts were finely modulated. By increasing x from 5 to 40, the morphology of the HZ5-2.5/x changed from unilamellar assembly with narrow a–c plane to intertwined nanosheets with wide a–c plane and multilamellar nanosheets with house-of-cards morphology. The thickness of these nanosheets was almost 8–10 nm. In addition, selectivity to light olefins reached 70.7% for the HZ5-2.5/10 catalyst, which was 6.6% higher than that for CZSM-5 (64.1%). Furthermore, the MFI zeolite nanosheets exhibited better anticoking stability within the 60 h reaction time compared to conventional ZSM-5 zeolite, which could be attributed to the short diffusion path and hierarchical porosity. This work will provide valuable insights into the rational design of novel zeolite catalysts for the efficient cracking of hydrocarbons.

Al2O3 supports were synthesized by the hydrothermal method and PtSn/Al2O3 catalysts were prepared by incipient-wetness impregnation method. The influence of the ratio of urea to Al(NO3)3·9H2O on the structure and catalytic performance for propane dehydrogenation was investigated. The catalysts were characterized by XRD, N2 adsorption–desorption, SEM, H2-TPR, NH3-TPD and Raman. The results show that the ratios of urea to Al(NO3)3·9H2O influence the morphology and phy-chemical properties of Al2O3 support, which influence the dispersion of PtSn active sites and the interaction of Pt and Sn on PtSn/Al2O3 catalysts. The PtSn/Al2O3-9 catalyst possesses the highest interaction of Pt and Sn, which result in high dispersion of active sites. The PtSn/Al2O3-9 catalyst shows high propane conversion and low deactivation rate among these catalysts.

Solvent-free synthesis methodology is a promising technique for the green and sustainable preparation of zeolites materials. In this work, a solvent-free route was developed to synthesize SAPO-34 zeolite. The characterization results indicated that the crystal size, texture properties, acidity and Si coordination environment of the resulting SAPO-34 were tuned by adjusting the SiO2/Al2O3 molar ratio in the starting mixture. Moreover, the acidity of SAPO-34 zeolite was found to depend on the Si coordination environment, which was consistent with that of SAPO-34 zeolite synthesized by the hydrothermal method. At an SiO2/Al2O3 ratio of 0.6, the SP-0.6 sample exhibited the highest conversion of 1-butene (82.8%) and a satisfactory yield of light olefins (51.6%) in the catalytic cracking of 1-butene, which was attributed to the synergistic effect of the large SBET (425 m2/g) and the abundant acid sites (1.82 mmol/g). This work provides a new opportunity for the design of efficient zeolite catalysts for industrially important reactions.

A set of classic molecular dynamics simulations at a cooling rate of 0.1 K/ps have been performed to investigate the effect of pressure ranging from 0 to 4 GPa on the solidification of liquid Mg 70 Zn 30 alloy, by means of the average atomic energy, the largest standard cluster analysis and 3D visualization. It is found that pressure plays an important role in both the glass transition and the structure of the final solid. T g - P ( T g is the end temperature of the glass transition) is a monotonically increasing curve with the increase rate decreases significantly at P  > 0.1 GPa. However, the structure parameters based on short-range order and icosahedrons are not monotonically dependent on pressure. Interestingly, the pressure dependence of the structure parameters based on topologically close-packed (TCP) structures is highly consistent with T g - P . Therefore, TCP is an essential characteristic and plays an important role in glass transition. In addition, the pressure enhances the contribution of Mg atoms to the formation of Zn-rich TCP structures. These findings shed new light on understanding the pressure-structure relationship of metallic glasses.

Endometrial carcinoma (EC) is one of the most common gynecologic malignancies, with increasing global morbidity and mortality rates. Curcumol, a sesquiterpenoid hemicrystalline compound, exhibits notable pharmacological effects, including anticancer, anti-inflammatory, and antiviral properties. This study aims to explore the molecular mechanisms through which curcumol exerts its effects in the treatment of EC. Network pharmacology, data mining and machine learning were used to integrate curcumol and EC targets. R and online databases were applied to screen core targets. The core targets were verified by molecular docking, molecular dynamics simulation, ceRNA network regulation, clinical sample staining, and immunoinfiltration analysis. Progesterone Receptor (PGR) and Ribosomal protein S6 kinase (RPS6KA1) were identified as two core targets in the cancer risk prognostic model. Survival analysis indicated that high expression of PGR and RPS6KA1 is associated with prolonged survival in patients with EC. The HPA validation confirmed the low expression of PGR and high expression of RPS6KA1 in EC tissues. Molecular docking and simulation confirmed strong binding affinities between curcumol and the PGR and RPS6KA1 targets. Myc-associated zinc finger protein (MAZ) was a regulator of both PGR and RPS6KA1. Additionally, KCNQ1OT1 and chr22-38_28785274-29006793.1 were found to jointly regulate PGR and RPS6KA1 through various miRNAs, contributing to the pathogenesis of EC. Through multi-omics analysis, we conclude that curcumol exerts its anticancer effects primarily through the core targets PGR and RPS6KA1 in the treatment of EC.