Supported rhodium nanoparticles (NPs) are well-known for catalyzing methanation in CO 2 hydrogenation. Now we demonstrate that the selectivity in this process can be optimized for CO production by choice of molecular sieve crystals as supports. The NPs are enveloped within the crystals with controlled nanopore environments that allow tuning of the catalytic selectivity to minimize methanation and favor the reverse water−gas shift reaction. Pure silica MFI (S-1)-fixed rhodium NPs exhibited maximized CO selectivity at high CO 2 conversions, whereas aluminosilicate MFI zeolite-supported rhodium NPs displayed high methane selectivity under the equivalent conditions. Strong correlations were observed between the nanoporous environment and catalytic selectivity, indicating that S-1 minimizes hydrogen spillover and favors fast desorption of CO to limit deep hydrogenation. Materials in this class appear to offer appealing opportunities for tailoring selective supported catalysts for a variety of reactions.

Nonoxidative dehydrogenation is promising for production of light olefins from shale gas, but current technology relies on precious Pt or toxic Cr catalysts and suffers from thermodynamically oriented coke formation. To solve these issues, the earth-abundant iron catalyst is employed, where Fe species are effectively modulated by siliceous zeolite, which is realized by the synthesis of Fe-containing MFI siliceous zeolite in the presence of ethylenediaminetetraacetic sodium (FeS-1-EDTA). Catalytic tests in ethane dehydrogenation show that this catalyst has a superior coke resistance in a 200 h run without any deactivation with extremely high activity and selectivity (e.g., 26.3% conversion and over 97.5% selectivity to ethene in at 873 K, close to the thermodynamic equilibrium limitation). Multiple characterizations demonstrate that the catalyst has uniformly and stably isolated Fe sites, which improves ethane dehydrogenation to facilitate the fast desorption of hydrogen and olefin products in the zeolite micropores and hinders the coke formation, as also identified by density functional calculations.

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We have synthesized a core@shell nanocomposite using biocompatible bovine serum albumin (BSA) as the core and a pH-sensitive metal-organic framework (MOF) as the shell. Doxorubicin (DOX)/BSA nanoparticles as cores have been prepared. A zeolitic imidazolate framework-8 (ZIF-8) layer has been coated on the outer surface of the DOX/BSA core. The ZIF layer acts as a capsule for the safe storage of DOX under physiological conditions. An efficient pH-responsive drug delivery system using a BSA/DOX@ZIF, in which the drug is not released in PBS at pH 7.4 but is released at low pH (5.0-6.0), has been constructed. Compared to the pure ZIF, a better biocompatibility has been obtained using the BSA/DOX@ZIF. The BSA/DOX@ZIF shows a much higher efficacy than free DOX against the breast cancer cell line MCF-7. The positive charges on the outer surface of the BSA/DOX@ZIF also improve its cellular uptake.

The empirical optimization of the preparation of catalytically active copper-containing catalysts is far more advanced than the fundamental understanding of the catalyst performance because of the structural complexity of the catalysts. Here, we demonstrate the interplay between the catalyst structure and CO 2 hydrogenation on Cu catalysts boosted with nickel species. The nickel dispersion on copper markedly affects the CO 2 dissociation activity and catalytic reaction pathways, thus resulting in distinctive catalytic activity and selectivity attributed to Ni. Specifically, the catalyst incorporating nickel alloyed in copper maximizes the synergy between the two metals and is characterized by conversions close to the thermodynamic equilibrium to CO as a productwith switched off methanationover a wide temperature range. Catalyst performance data, spectra characterizing the catalyst, and theoretical results demonstrate that surface copper with adjacent nickel atoms efficiently activates CO 2 via a redox mechanismwith adsorption of CO being suppressedso that methanation associated with deep hydrogenation of CO is inhibited. The results of this investigation highlight the importance of structures with copper-adjacent-nickel, which appear to offer appealing opportunities for tailoring efficient copper-containing catalysts for CO 2 hydrogenation.

Nanomaterials are known to exhibit a number of interesting physical and chemical properties for various applications, including energy conversion and storage, nanoscale electronics, sensors and actuators, photonics devices and even for biomedical purposes. In the past decade, laser as a synthetic technique and laser as a microfabrication technique facilitated nanomaterial preparation and nanostructure construction, including the laser processing-induced carbon and non-carbon nanomaterials, hierarchical structure construction, patterning, heteroatom doping, sputtering etching, and so on. The laser-induced nanomaterials and nanostructures have extended broad applications in electronic devices, such as light–thermal conversion, batteries, supercapacitors, sensor devices, actuators and electrocatalytic electrodes. Here, the recent developments in the laser synthesis of carbon-based and non-carbon-based nanomaterials are comprehensively summarized. An extensive overview on laser-enabled electronic devices for various applications is depicted. With the rapid progress made in the research on nanomaterial preparation through laser synthesis and laser microfabrication technologies, laser synthesis and microfabrication toward energy conversion and storage will undergo fast development.