Ga-doped ZnO nanoparticles for enhanced CO gas sensing applications.

Gallium-doped zinc oxide (GZO) has demonstrated significant potential in gas-sensing applications due to its enhanced electrical and chemical properties. This study focuses on the synthesis, characterization, and gas-sensing performance of GZO nanoparticles (NPs), specifically targeting CO₂ detection, which is crucial for environmental monitoring and industrial safety. The GZO samples were synthesized using a sol-gel method, and their crystal structure was determined through X-ray diffraction (XRD), confirming the successful incorporation of gallium into the ZnO lattice.

Engineering of self-assembled silver-peptide colloidal nanohybrids with enhanced biocompatibility and antibacterial activity.

Several bacterial strains have developed resistance against commercial antibiotics, and interestingly, supramolecular nanomaterials have shown considerable advantages for antibacterial applications. However, the main challenges in adopting nanotechnology for antibacterial studies are random aggregation, compromised toxicity, multi-step preparation approaches, and unclear structure-function properties. Herein, we designed the amphiphilic tripeptide that acts as a reducing and capping agent for silver metal to form silver-peptide colloidal nanohybrids with the mild assistance of UV light (254 nm) through the photochemical reduction method.

Kinetic Insights into Methanol Synthesis from CO Hydrogenation at Atmospheric Pressure over Intermetallic PdGa Catalyst.

This study presents a single-site microkinetic model for methanol synthesis by CO hydrogenation over intermetallic PdGa/SiO. A reaction path analysis (RPA) combining theoretical results and realistic catalyst surface reaction data is established to elucidate the reaction mechanism and kinetic models of CO hydrogenation to methanol and CO. The RPA leads to the derivation of rate expressions for both reactions without presumptions about the most abundant reactive intermediate (MARI) and rate-determining step (rds).

Nanoscale mapping of residual stresses in Al 2024 alloys using correlative and multimodal scanning transmission electron microscopy.

A methodology for the mapping of residual stresses in metal alloys has been developed by analyzing an isotropic and homogeneous Al2024 alloy with scanning transmission electron microscopy (STEM), combined with diffraction (4DSTEM) and electron energy loss spectroscopy (STEM-EELS) techniques of TEM. The investigations on the alloy's microstructure and elemental distributions were also carried out with conventional dark-field STEM (DFSTEM) and X-ray energy dispersive (EDS) techniques, respectively. Using the STEM-EELS technique, the Young's modulus () is mapped in the (001) plane of the Al alloy in the same regions where the residual strain maps are generated in [ 00] and [010] directions by using 4DSTEM technique.

Evolution of Oxygen Vacancy Sites in Ceria-Based High-Entropy Oxides and Their Role in N Activation.

In this work, a relatively new class of materials, rare earth (RE) based high entropy oxides (HEO) are discussed in terms of the evolution of the oxygen vacant sites (O) content in their structure as the composition changes from binary to HEO using both experimental and computational tools; the composition of HEO under focus is the CeLaPrSmGdO due to the importance of ceria-related (fluorite) materials to catalysis. To unveil key features of quinary HEO structure, ceria-based binary CePrO and CeLaO compositions as well as SiO, the latter as representative nonreducible oxide, were used and compared as supports for Ru (6 wt % loading). The role of the O in the HEO is highlighted for the ammonia production with particular emphasis on the N dissociation step (N → N) over a HEO; the latter step is considered the rate controlling one in the ammonia production.

Major Role of Multiscale Entropy Evolution in Complex Systems and Data Science.

Complex systems are prevalent in various disciplines encompassing the natural and social sciences, such as physics, biology, economics, and sociology. Leveraging data science techniques, particularly those rooted in artificial intelligence and machine learning, offers a promising avenue for comprehending the intricacies of complex systems without necessitating detailed knowledge of underlying dynamics. In this paper, we demonstrate that multiscale entropy (MSE) is pivotal in describing the steady state of complex systems.

Gold nanoparticles spectral CT imaging and limit of detectability in a new materials contrast-detail phantom.

This study involves the synthesis, characterization, and spectral photon counting CT (SPCCT) imaging of gold nanoparticles tailored for enhancing the contrast of small cancer lesions. We used the modified Turkevich method to produce thiol-capped gold nanoparticles (AuNPs) at different concentrations (20, 15, 10, 5, 2.5, 1.

In Situ Growth of Interfacially Nanoengineered 2D-2D WS/TiCT MXene for the Enhanced Performance of Hydrogen Evolution Reactions.

In line with current research goals involving water splitting for hydrogen production, this work aims to develop a noble-metal-free electrocatalyst for a superior hydrogen evolution reaction (HER). A single-step interfacial activation of TiCT MXene layers was employed by uniformly growing embedded WS two-dimensional (2D) nanopetal-like sheets through a facile solvothermal method. We exploited the interactions between WS nanopetals and TiCT nanolayers to enhance HER performance.

Synthesis, characterization, and preliminary insights of ZnFeO nanoparticles into potential applications, with a focus on gas sensing.

This work presents a hydrothermal-based facile method for synthesizing ZnFeO whose size can be controlled with the concentration of sodium acetate used as a fuel and its physical changes at nanoscales when exposed to two different gases. The structural, morphological, compositional, and electronic properties of the synthesized samples are also presented in this paper. The crystal structure of the synthesized samples was determined using an X-ray Diffractometer (XRD).

Synthesis of Mesoporous Carbon Adsorbents Using Biowaste Crude Glycerol as a Carbon Source via a Hard Template Method for Efficient CO Capture.

Biowaste utilization as a carbon source and its transformation into porous carbons have been of great interest to promote environmental remediation owing to biowaste's cost-effectiveness and useful physicochemical properties. In this work, crude glycerol (CG) residue from waste cooking oil transesterification was employed to fabricate mesoporous crude glycerol-based porous carbons (CGPCs) using mesoporous silica (KIT-6) as a template. The obtained CGPCs were characterized and compared to commercial activated carbon (AC) and CMK-8, a carbon material prepared using sucrose.

Synthesis of Graphene Oxide from Sugarcane Dry Leaves by Two-Stage Pyrolysis.

Natural or synthetic graphite as precursors for the preparation of graphene oxide (GO) have constraints due to their limited availability, high reaction temperature for processing of synthetic graphite and higher generation cost. The use of oxidants, long reaction duration, the generation of toxic gases and residues of inorganic salts, the degree of hazard and low yield are some of the disadvantages of the oxidative-exfoliation methods. Under these circumstances, biomass waste usage as a precursor is a viable alternative.

Enhanced Graphene Oxide Electrical Properties for Thin-Film Electronics Using an Active/Shrinkable Substrate.

The advances in material science along with the development of fabrication techniques have enabled the realization of thin-film-based electronics on active substrates. This has substantially enhanced and supported the deployment of electronic devices in several emerging applications with flexible functionality. In this work, we report a novel fabrication of graphene oxide (GO)-based memristor devices on an active/shrinkable substrate.

Carbon dioxide adsorbents from flame-made diesel soot nanoparticles.

Carbon dioxide (CO) is the top contributor to global warming. On the other, soot particles formed during fuel combustion and released into the atmosphere are harmful and also contribute to global warming. It would therefore be highly advantageous to capture soot and make use of it as a feedstock to synthesize carbon-based materials for applications such as carbon dioxide adsorption.

Cryo-electron structures of the extreme thermostable enzymes Sulfur Oxygenase Reductase and Lumazine Synthase.

Thermostable enzymes have the potential for use in a wide variety of biotechnological applications. Cryo-electron microscopy (cryo-EM) enables the imaging of biomolecules in their native aqueous environment. Here, we present high resolution cryo-EM structures of two thermostable enzymes that exhibit multimeric cage-like structures arranged into two different point-group symmetries.

Carbon Nanostructure/Zeolite Y Composites as Supports for Monometallic and Bimetallic Hydrocracking Catalysts.

In this study, we examine the effect of integrating different carbon nanostructures (carbon nanotubes, CNTs, graphene nanoplatelets, GNPs) into Ni- and Ni-W-based bi-functional catalysts for hydrocracking of heptane performed at 400 °C. The effect of varying the SiO2/Al2O3 ratio of the zeolite Y support (between 5 and 30) on the heptane conversion is also studied. The results show that the activity, in terms of heptane conversion, followed the order CNT/Ni-ZY5 (92%) > GNP/Ni-ZY5 (89%) > CNT/Ni-W-ZY30 (86%) > GNP/Ni-W-ZY30 (85%) > CNT/Ni-ZY30 (84%) > GNP/Ni-ZY30 (83%).

Decoupling the Chemical and Mechanical Strain Effect on Steering the CO Activation over CeO-Based Oxides: An Experimental and DFT Approach.

Doped ceria-based metal oxides are widely used as supports and stand-alone catalysts in reactions where CO is involved. Thus, it is important to understand how to tailor their CO adsorption behavior. In this work, steering the CO activation behavior of Ce-La-Cu-O ternary oxide surfaces through the combined effect of chemical and mechanical strain was thoroughly examined using both experimental and ab initio modeling approaches.

Coupling Long-Range Facet Junction and Interfacial Heterojunction via Edge-Selective Deposition for High-Performance Z-Scheme Photocatalyst.

The construction of photocatalytic systems that have strong redox capability, effective charge separation, and large reactive surfaces is of great scientific and practical interest. Herein, an edge-connected 2D/2D Z-scheme system that combines the facet junction and the interfacial heterojunction to achieve effective long-range charge separation and large reactive surface exposure is designed and fabricated. The heterostructure is realized by the selective growth of 2D-layered MoS nanoflakes on the edge-sites of thin TiO nanosheets via an Au-promoted photodeposition method.

Compact broadband ( O, E, S, C, L & U bands) silicon TE-pass polarizer based on ridge waveguide adiabatic S-bends.

A compact, ultra-broadband and high-performance silicon TE-pass polarizer is proposed and demonstrated experimentally. It is based on partially-etched (ridge) waveguide adiabatic S-bends, input/output tapers and side gratings on a silicon-on-insulator (SOI) platform. A compact footprint and weak back reflections are obtained due to the bent waveguide and the tapers, respectively.

Production of Size-Controlled Gold Nanoclusters for Vapor-Liquid-Solid Method.

This study demonstrated the deposition of size-controlled gold (Au) nanoclusters via direct-current magnetron sputtering and inert gas condensation techniques. The impact of different source parameters, namely, sputtering discharge power, inert gas flow rate, and aggregation length on Au nanoclusters' size and yield was investigated. Au nanoclusters' size and size uniformity were confirmed via transmission electron microscopy.

A user-friendly FIB lift-out technique to prepare plan-view TEM sample of 2D thin film materials.

Plan-view transmission electron microscopy (TEM) or electron diffraction imaging of a bulk or 2D material can provide detailed information about the structural or atomic arrangement in the material. A systematic and easily implementable approach to preparing site-specific plan-view TEM samples for 2D thin film materials using FIB is discussed that could be routinely used. The methodology has been successfully applied to prepare samples from 2D materials such as, MoS thin film, vertically oriented graphene film (VG), as well as heterostructure material SnTiS.

Design Aspects of Doped CeO for Low-Temperature Catalytic CO Oxidation: Transient Kinetics and DFT Approach.

CO elimination through oxidation over highly active and cost-effective catalysts is a way forward for many processes of industrial and environmental importance. In this study, doped CeO with transition metals (TM = Cu, Co, Mn, Fe, Ni, Zr, and Zn) at a level of 20 at. % was tested for CO oxidation.

Engineering Band-Type Alignment in CsPbBr Perovskite-Based Artificial Multiple Quantum Wells.

Semiconductor heterostructures of multiple quantum wells (MQWs) have major applications in optoelectronics. However, for halide perovskites-the leading class of emerging semiconductors-building a variety of bandgap alignments (i.e.

Phonon Dynamics and Transport Properties of Copper Thiocyanate and Copper Selenocyanate Pseudohalides.

The phonon transport properties of CuSCN and CuSeCN have been investigated using the density functional theory and semiclassical Boltzmann transport theory. The Perdew-Burke-Ernzerhof functional shows an indirect (direct) electronic band gap of 2.18 eV (1.