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Highlights  A fast and efficient method was developed for the synthesis of HKUST-1  Synthesis was conducted under low temperature and atmospheric pressure  The MOFs was synthesized in nano-scale with high BET surface area and high yield  Activation agent has shown significant influence on BET surface area of the MOFs  The HKUST-1 prepared shows excellent CO2 uptake capacity 2

In this research, ab initio calculations and experimental approach were adopted to reveal the mechanism of Hg 0 adsorption on MoS2 nanosheets that contain various types of defects. The ab initio calculation showed that, among different structural defects, S vacancies (Vs) in the MoS2 nanosheets exhibited outstanding potential to strongly adsorb Hg 0. The MoS2 material was then prepared in a controlled manner under conditions, such as temperature, concentration of precursors, etc., that were determined by adopting the new method developed in this study. Characterisation confirmed that the MoS2 material is of graphene-like layered structure with abundant structural defects. The integrated dynamic and steady state (IDSS) testing demonstrated that the Vs-rich nanosheets showed excellent Hg 0 adsorption capability. In addition, ab initial calculation on charge density difference, PDOS, and adsorption pathways revealed that the adsorption of Hg 0 on the Vs-rich MoS2 surface is non-activated chemisorption.

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The current study reviews the recent development in the direct conversion of methane into syngas, methanol, light olefins, and aromatic compounds. For syngas production, nickelbased catalysts are considered as a good choice. Methane conversion (84%) is achieved with nearly no coke formation when the 7% Ni-1%Au/Al2O3 catalyst is used in the steam reforming of methane (SRM), whereas for dry reforming of methane (DRM), a methane conversion of 17.9% and CO2 conversion of 23.1% are found for 10%Ni/ZrOxMnOx/SiO2 operated at 500 o C. The progress of direct conversion of methane to methanol is also summarized with an insight into its selectivity and/or conversion, which shows that in liquid-phase heterogeneous systems, high selectivity (>80%) can be achieved at 50 o C, but the conversion is low. The latest development of nonoxidative coupling of methane (NOCM) and oxidative coupling of methane (OCM) for the production of olefins is also reviewed. The Mn2O3-TiO2-Na2WO4/SiO2 catalyst is reported to show the high C2 yield (22%) and a high selectivity toward C2 (62%) during the OCM at 650 o C. For NOCM, 98% selectivity of ethane can be achieved when a tantalum hydride catalyst supported on silica is used. In addition, the Mo-based catalysts are the most suitable for the preparation of aromatic compounds from methane.

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In this study, a new "one-pot" synthesis method was developed for the fabrication of HKUST-1 on MoS 2 quantum dots (QDs) to form a core−shell structure. It is proved that the HKUST-1 self-assembles on MoS 2 QDs to form a core−shell structure, which exhibits a high surface area of 1638.9 m 2 /g and enhances CO 2 uptake to 4.64 mmol/g as compared with HKUST-1 alone. The density functional theory (DFT) calculations revealed that the growth of HKUST-1 on MoS 2 QDs starts from the adsorption of Cu 2+ cations on the MoS 2 (001), followed by the Cu 2+ cations bonding with trimesic acid (TMA) anions. In addition, the interactions between a CO 2 molecule and the (MoS 2 + SBU) (secondary building unit = SBU) unit were studied using DFT calculations to show the mechanism of CO 2 adsorption on the MoS 2 /HKUST-1 core−shell composite. It is found that the MoS 2 QDs induce stronger electrostatic forces on CO 2 than HKUST-1 alone, which subsequently contributes to enhancing the adsorption of CO 2 on the MoS 2 /HKUST-1 core−shell composite.

Over the past two decades, there has been a growing body of work on wireless devices that can operate on the length scales of biological cells and even smaller. A...