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Supercapacitors (SCs) have the unique ability to rapidly recharge while providing substantial power output. Metal‐organic frameworks (MOFs) are emerging as promising electrode materials for SCs due to their high porosity, ease of synthesis, tunable pore size distribution, and exceptional structural adaptability. This study presents a facile and cost‐effective method, namely, laser ablation synthesis in solution (LASiS), for the synthesis of bimetallic MOFs composited with reduced graphene oxide (rGO), namely, ZnCo bi‐MOF‐rGO hybrid nanocomposite (HNC). Comprehensive analyses demonstrate that ZnCo bi‐MOF‐rGO has a high specific capacitance of 1092 F g−1 at 1.0 A g−1 in a 0.5 M Na3SO4 electrolyte. In addition, these bi‐MOF‐rGO composites have been successfully integrated with appropriate solvents, viscosity modifiers, in‐house synthesized porous carbon (PC), commercially available graphene, and binders into an active layer ink material for the development of high‐performance 3D printed SCs via sequential inkjet printing. To that end, the way has been paved for the incorporation of this class of material into energy storage applications, particularly in the fabrication of high‐performance printed electronics using laser‐induced materials. [ABSTRACT FROM AUTHOR]

Conversion of designer metal–organic frameworks (MOFs) into hybrid nanocomposites (HNCs) consisting of transition metal/metal oxides interfaced with carbon (C) matrices has emerged as a promising and economical alternative for the synthesis of oxygen reduction reaction (ORR) electrocatalysts, owing to their superior conductivity and high porosity. To that end, optimizing the performance of this class of material by tailoring its composition, structure, size, and morphology through an efficient synthesis route has become an active area of research. Specifically, this study employs Laser Ablation Synthesis in Solution in tandem with Galvanic Replacement Reaction (LASiS-GRR) technique as an environmentally friendly, facile, and rapid route for the design and synthesis of core–shell bimetallic zeolitic imidazolate framework (ZIF) heterostructures as bi-MOFs, and then uses pyrolytic postprocessing to yield hierarchical metal oxide/MOF-based functional HNCs as highly active ORR electrocatalysts. The LASiS-GRR technique employs high-energy laser plasma reactions as the rate-controlling step for initiating solution-phase galvanic reactions. The one-pot, two-step process introduced in this study enables tailoring of the composition, structure, size, and morphology of composite bi-MOFs comprising Co-based MOFs encapsulated in Zn-based porous crystals (Co/ZIF-67@Zn/ZIF-8). Pyrolytic postprocessing of these core–shell bi-MOF crystals leads to the creation of hierarchical ZnO@ZIF/C HNCs with superior ORR electrocatalytic performances under alkaline conditions. Overall, these findings not only elucidate the process by which LASiS-GRR protocols are optimized to tailor the morphology, structure, and composition of complex MOF structures but also demonstrate the superior performance and stability of the ensuing postpyrolyzed ZnO@ZIF/C HNCs as nonprecious metal-based ORR electrocatalysts, when compared to commonly used Pt- and Pt-group metal (PGM)-based electrocatalysts. [ABSTRACT FROM AUTHOR]

The article in Advanced Materials Technologies discusses the development of 3D printed supercapacitors using laser-derived hierarchical nanocomposites of bimetallic Co/Zn metal-organic framework and graphene oxide. Researchers led by Bamin Khomami demonstrate the synthesis of highly porous and electrically conductive hybrid nanocomposites for high-performance supercapacitors. These materials are utilized in additive manufacturing to create 3D printed supercapacitor devices with ZnCo bi-MOF-rGO electrodes via inkjet printing. [Extracted from the article]

Nanotechnology is a significant research tool for biological and medical research with major advancements achieved from nanoparticle (Np) applications in biosensing and biotherapeutics. For laser ablation synthesis in solution (LASiS) to be chosen by researchers for Np colloid production, the process must effectively compete with chemical synthesis in terms of produced colloid quality and productivity while taking advantage of LASiS benefits in terms of its 'green-synthesis' and single-step functionalisation abilities. In this work, a newly developed integrated LASiS Np manufacturing system is presented including a Np flow reactor design, an at-line Np size monitoring via 180° dynamic light scattering, and a UV-Vis spectroscopy system used to estimate colloid concentration and stability. The experimental outcomes are discussed in terms of Np productivity and quality via these at-line measurements from the UV-Vis and DLS systems. The developed instrument was validated via off-line SiNps DLS, UV-Vis and morphology tests via TEM. Ultra-high quality and nanoparticle fabrication rate efficiency was achieved and is reported here. [ABSTRACT FROM AUTHOR]

As nanomaterials find applications in an increasingly diverse range of fields such as wastewater treatment, biotechnology and flexible electronics, the demand for nanomaterials with specific properties has increased. This increase is coupled with an increasing emphasis on nanomaterials with highly specific properties for specialised applications. Industrially, nanomaterials are produced via wet-chemical techniques which employ the use of solvents and reagents which are environmentally harmful. As we move forward with the use of nanomaterials, the ability to produce nanomaterials in a sustainable manner has become a topic of great significance. Towards this end, Laser Ablation Synthesis in Solution (LASiS) is a physical production technique capable of producing tailored nanomaterial colloids in a sustainable manner. These colloids are produced by ablating a solid target immersed in a solvent using a laser. Typically, LASiS is conducted in a batch process and in small volumes limiting commercial viability. To overcome this, there has been a move towards the use of continuous production via LASiS using flow systems. This allows an increase in nanomaterial yield, resulting in colloid concentrations approaching those of commercial colloids. This work investigates a new production technique incorporating a laminar recirculatory flow system to produce stable high concentration nano-silver colloids. [ABSTRACT FROM AUTHOR]

Designing bioactive materials, with controlled metal ion release, exerting a significant biological action and associated to low toxicity for humans, is nowadays one of the most important challenges for our community. The most looked-for nanoantimicrobials are capable of releasing metal species with defined kinetic profiles, either by slowing down or inhibiting bacterial growth and pathogenic microorganism diffusion. In this study, laser ablation synthesis in solution (LASiS) has been used to produce bioactive Ag-based nanocolloids, in isopropyl alcohol, which can be used as water-insoluble nano-reservoirs in composite materials like poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Infrared spectroscopy was used to evaluate the chemical state of pristine polymer and final composite material, thus providing useful information about synthesis processes, as well as storage and processing conditions. Transmission electron microscopy was exploited to study the morphology of nano-colloids, along with UV-Vis for bulk chemical characterization, highlighting the presence of spheroidal particles with average diameter around 12 nm. Electro-thermal atomic absorption spectroscopy was used to investigate metal ion release from Ag-modified products, showing a maximum release around 60 ppb, which ensures an efficient antimicrobial activity, being much lower than what recommended by health institutions. Analytical spectroscopy results were matched with bioactivity tests carried out on target microorganisms of food spoilage. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are well-known for their antimicrobial effects and several groups are proposing them as active agents to fight antimicrobial resistance. A wide variety of methods is available for nanoparticle synthesis, affording a broad spectrum of chemical and physical properties. In this work, we report on AgNPs produced by laser ablation synthesis in solution (LASiS), discussing the major features of this approach. Laser ablation synthesis is one of the best candidates, as compared to wet-chemical syntheses, for preparing Ag nano-antimicrobials. In fact, this method allows the preparation of stable Ag colloids in pure solvents without using either capping and stabilizing agents or reductants. LASiS produces AgNPs, which can be more suitable for medical and food-related applications where it is important to use non-toxic chemicals and materials for humans. In addition, laser ablation allows for achieving nanoparticles with different properties according to experimental laser parameters, thus influencing antibacterial mechanisms. However, the concentration obtained by laser-generated AgNP colloids is often low, and it is hard to implement them on an industrial scale. To obtain interesting concentrations for final applications, it is necessary to exploit high-energy lasers, which are quite expensive. In this review, we discuss the pros and cons of the use of laser ablation synthesis for the production of Ag antimicrobial colloids, taking into account applications in the food packaging field. [ABSTRACT FROM AUTHOR]