2D transition metal dichalcogenides (TMDs) have received widespread interest by virtue of their excellent electrical, optical, and electrochemical characteristics. Recent studies on TMDs have revealed their versatile utilization as electrocatalysts, supercapacitors, battery materials, and sensors, etc. In this study, MoS2 nanosheets are successfully assembled on the porous VS2 (P‐VS2) scaffold to form a MoS2/VS2 heterostructure. Their gas‐sensing features, such as sensitivity and selectivity, are investigated by using a quartz crystal microbalance (QCM) technique. The QCM results and density functional theory (DFT) calculations reveal the impressive affinity of the MoS2/VS2 heterostructure sensor toward ammonia with a higher adsorption uptake than the pristine MoS2 or P‐VS2 sensor. Furthermore, the adsorption kinetics of the MoS2/VS2 heterostructure sensor toward ammonia follow the pseudo‐first‐order kinetics model. The excellent sensing features of the MoS2/VS2 heterostructure render it attractive for high‐performance ammonia sensors in diverse applications.
Porous nanomaterials with superior peroxidase mimetic activity (nanozyme) at room temperature have gained increasing attention as potential alternatives to natural peroxidase enzymes. Herein, we report the application of porous iron oxide nanoflakes (IONFs), synthesized using the combination of solvothermal method and high-temperature calcination as peroxidase nanozyme for the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H 2 O 2 . The four IONF catalysts possess porous structures with a wide pore size distribution between 2-30 nm and high specific surface areas around to 200 m 2 g À1 . The increase of calcination temperature of the IONFs from 250 8C to 400 8C resulted in a gradual decrease in their specific surface area and Michaelis-Menten constant (K m ) for TMB oxidation. The optimum IONF sample showed a much lower K m at 0.24 mM (towards TMB) compared to natural enzyme horseradish peroxidase (HRP) at 0.434 mM, revealing the promising potential of the asprepared IONFs as alternatives to HRP for biosensing applications.[a] Dr.
What was the biggest surprise?It would be the controllable selectivity to 5-formyl-2-furoic acid (FFCA) and2 ,5-furandicarboxylic acid (FDCA). Selectivity to the desired product is alwaysaproblem in the oxidation of 5-hydroxymethylfurfural (HMF), not only because HMF is easily converted to other chemicals, but also because there are several intermediate stages duringt he sequential oxidationp rocess. However,o wing to the different reactionr ates of each intermediate, we found that we are ablet oc ontrol the reaction product to be either FFCA or FDCA by simply adjusting the ratio between HMF and the catalyst.
Selective hydrogenation of nitriles is an industrially relevant synthetic route for the preparation of primary amines. Amorphous metal–boron alloys have a tunable, glass‐like structure that generates a high concentration of unsaturated metal surface atoms that serve as active sites in hydrogenation reactions. Here, a method to create nanoparticles composed of mesoporous 3D networks of amorphous nickel–boron (Ni‐B) alloy is reported. The hydrogenation of benzyl cyanide to β‐phenylethylamine is used as a model reaction to assess catalytic performance. The mesoporous Ni‐B alloy spheres have a turnover frequency value of 11.6 h−1, which outperforms non‐porous Ni‐B spheres with the same composition. The bottom‐up synthesis of mesoporous transition metal–metalloid alloys expands the possible reactions that these metal architectures can perform while simultaneously incorporating more Earth‐abundant catalysts.
Metal oxide nanoparticles synthesized by the biological method represent the most recent research in nanotechnology. This study reports the rapid and ecofriendly approach for the synthesis of CeO2 nanoparticles mediated using the Abelmoschus esculentus extract. The medicinal plant extract acts as both a reducing and stabilizing agent. The characterization of CeO2 NPs was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxicity of green synthesized CeO2 was assessed against cervical cancerous cells (HeLa). The exposure of CeO2 to HeLa cells at 10–125 µg/mL caused a loss in cellular viability against cervical cancerous cells in a dose-dependent manner. The antibacterial activity of the CeO2 was assessed against S. aureus and K. pneumonia. A significant improvement in wound-healing progression was observed when cerium oxide nanoparticles were incorporated into the chitosan hydrogel membrane as a wound dressing.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.