Improvements in the utilization of calcium carbonate in promoting sustainability and environmental health.

Calcium carbonate (CaCO) is an incredibly abundant mineral on Earth, with over 90% of it being found in the lithosphere. To address the CO crisis and combat ocean acidification, it is essential to produce more CaCO using various synthetic methods. Additionally, this approach can serve as a substitute for energy-intensive processes like cement production.

Heterolytic C-H Activation Routes in Catalytic Dehydrogenation of Light Alkanes on Lewis Acid-Base Pairs at ZrO Surfaces.

Alkane dehydrogenation is an enabling route to make alkenes useful as chemical intermediates. This study demonstrates the high reactivity of Lewis acid-base (LAB) site pairs at ZrO powders for dehydrogenation of C-C alkanes and the essential requirement for chemical treatments to remove strongly bound HO and CO titrants to avoid the high temperatures required for their desorption and the concomitant loss of active sites through sintering and annealing of ZrO crystallites. The energies and free energies of bound intermediates and transition states from density functional theory (DFT), taken together with kinetic analysis and isotopic methods, demonstrated the kinetic relevance and heterolytic character of the first C-H activation at terminal C-atoms for all alkanes with a modest activation barrier (84 kJ mol) at essentially bare Zr-O LAB site pairs.

Palladium-Catalyzed Amination of Aryl Halides with Aqueous Ammonia and Hydroxide Base Enabled by Ligand Development.

The conversion of aryl halides to primary arylamines with a convenient and inexpensive source of ammonia has been a long-standing synthetic challenge. Aqueous ammonia would be the most convenient and least expensive form of ammonia, but such a palladium-catalyzed amination reaction with a high concentration of water faces challenges concerning catalyst stability and competing hydroxylation, and palladium-catalyzed reactions with this practical reagent are rare. Further, most reactions with ammonia to form primary amines are conducted with -butoxide base, but reactions with ammonium hydroxide would contain hydroxide as base.

Diverse functional polyethylenes by catalytic amination.

Functional polyethylenes possess valuable bulk and surface properties, but the limits of current synthetic methods narrow the range of accessible materials and prevent many envisioned applications. Instead, these materials are often used in composite films that are challenging to recycle. We report a Cu-catalyzed amination of polyethylenes to form mono- and bifunctional materials containing a series of polar groups and substituents.

Chemical Modification of Oxidized Polyethylene Enables Access to Functional Polyethylenes with Greater Reuse.

Polyethylene is a commodity material that is widely used because of its low cost and valuable properties. However, the lack of functional groups in polyethylene limits its use in applications that include adhesives, gas barriers, and plastic blends. The inertness of polyethylene makes it difficult to install groups that would enhance its properties and enable programmed chemical decomposition.

Understanding the Structural Evolution of IrFeCoNiCu High-Entropy Alloy Nanoparticles under the Acidic Oxygen Evolution Reaction.

High-entropy alloy (HEA) nanoparticles are promising catalyst candidates for the acidic oxygen evolution reaction (OER). Herein, we report the synthesis of IrFeCoNiCu-HEA nanoparticles on a carbon paper substrate via a microwave-assisted shock synthesis method. Under OER conditions in 0.

Hierarchical zinc oxide materials with multiple porosity prepared by ultrafast temperature gradient chemical gas-phase synthesis.

The preparation of materials characterized by three types of porosity could be prepared by a continuous chemical gas-phase method. The multistep formation mechanism involves a critical temperature gradient and occurs within seconds. The resulting hollow aerogel materials show superior properties as gas sensors in comparison to materials constructed from compact nanoparticles.

A new class of surfactants with multinuclear, inorganic head groups.

The main ability of amphiphilic molecules is to alter the energy of interfaces. They aid in the formation of various materials characterized by a high surface to volume ratio. Furthermore, amphiphiles tend to self-organize into structures of higher complexity.

Chromium containing zinc oxide materials from organobimetallic precursors.

Zinc oxide has become one of the most important semiconductor materials and it possesses a multitude of properties and applications. An even wider spectrum of properties can be envisioned if an additional element is introduced. On the cation side there is large interest in the combination of ZnO with paramagnetic metal centres like Cr(III).