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Carbon capture and utilization (CCU) technologies present a promising solution for converting CO2 emissions into valuable products. Here we show how amines, such as monoethanolamine (MEA) and 2-amino-2-methyl-1-propanol (AMP), influence the electrochemical CO2 reduction process in an integrated CCU system. Using in situ spectroscopic techniques, we identify the key roles of carbamate bond strength, proton shuttling, and amine structure in dictating reaction pathways on copper (Cu) and lead (Pb) electrodes. Our findings demonstrate that on Cu electrodes, surface blockage by ammonium species impedes CO₂ reduction, whereas on Pb electrodes, proton shuttling enhances the production of hydrocarbon products. This study provides additional insights into optimizing CCU systems by tailoring the choice of amines and electrode materials, advancing the selective conversion of CO₂ into valuable chemicals. Integrated carbon capture and utilization (CCU) systems offer a sustainable approach to converting CO₂ emissions into valuable chemicals. Here, the authors report the choice of amine and electrode materials significantly impact the efficiency and selectivity of CO2 reduction in CCU processes. [ABSTRACT FROM AUTHOR]

Background: Diabetic foot ulcers (DFU) are a costly complication of diabetes mellitus (DM), with significant implications for the patient and the healthcare professionals that treat them. The primary objective of this study was to evaluate if there were improved healing rates in patients with a DFU that were taking a statin medication compared to those patients with a DFU who were not taking a statin medication. Secondary outcomes assessed were correlations with wound healing or statin use on data obtained from retrospective chart review., Methods: A case-control series was performed to obtain appropriate demographic information, comorbid conditions, laboratory values, and physical examination findings. From the time of presentation with DFU, these patients were followed for 12 weeks to evaluate for healing. Healing was defined as full epithelialization of the DFU with no further drainage. Wound healing and statin use correlation testing was then done for collected variables and each cohort. Chi square and Pearson correlation were then performed to identify any significant correlations. All p-values were two-sided, and findings were considered statistically significant at p < 0.05., Results: Our study identified 109 patients, 75 patients with a DFU on statin medication and 34 patients with a DFU not on statin medication. The statin cohort was more likely to be older, less than 5-year duration of diabetes, have more comorbidities, decreased low-density lipoprotein (LDL) cholesterol, and decreased total cholesterol (p < 0.05). Among those patients taking a statin medication, 48.0% (36/75) healed their DFU within 12 weeks. Among those patients not taking a statin medication, 44.1% (15/34) healed their DFU within 12 weeks. No correlation was noted between wound healing and statin use (p = 0.7). For wound healing, a negative correlation was noted for prior minor amputations (p < 0.05). For statin use, correlations were noted for age, duration of DM, LDL cholesterol level, total cholesterol level, HTN, CAD, and HLD (p < 0.05)., Conclusions: Statin medication use did not influence DFU healing rates between cohorts. There was a correlation noted between wound healing and prior minor amputations and between statin use and age, duration of DM, LDL cholesterol, total cholesterol, HTN, CAD and HLD. Additionally, we observed no correlation between DFU healing rates and use of a statin medication., (© 2024. The Author(s).)

Alkaline water electrolysis (AWE) is among the most developed technologies for green hydrogen generation. Despite the tremendous achievements in boosting the catalytic activity of the electrode, the operating current density of modern water electrolyzers is yet much lower than the emerging approaches such as the proton-exchange membrane water electrolysis (PEMWE). One of the dominant hindering factors is the high overpotentials induced by the gas bubbles. Herein, the bubble dynamics via creating the superaerophobic electrode assembly is optimized. The patterned Co-Ni phosphide/spinel oxide heterostructure shows complete wetting of water droplet with fast spreading time (≈300 ms) whereas complete underwater bubble repelling with 180° contact angle is achieved. Besides, the current collector/electrode interface is also modified by coating with aerophobic hydroxide on Ti current collector. Thus, in the zero-gap water electrolyzer test, a current density of 3.5 A cm -2 is obtained at 2.25 V and 85 °C in 6 m KOH, which is comparable with the state-of-the-art PEMWE using Pt-group metal catalyst. No major performance degradation or materials deterioration is observed after 330 h test. This approach reveals the importance of bubble management in modern AWE, offering a promising solution toward high-rate water electrolysis., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Electrochemical water splitting is one of the most sustainable approaches for generating hydrogen. Because of the inherent constraints associated with the architecture and materials, the conventional alkaline water electrolyzer and the emerging proton exchange membrane electrolyzer are suffering from low efficiency and high materials/operation costs, respectively. Herein, we design a membrane-free flow electrolyzer, featuring a sandwich-like architecture and a cyclic operation mode, for decoupled overall water splitting. Comprised of two physically-separated compartments with flowing H 2 -rich catholyte and O 2 -rich anolyte, the cell delivers H 2 with a purity >99.1%. Its low internal ohmic resistance, highly active yet affordable bifunctional catalysts and efficient mass transport enable the water splitting at current density of 750 mA cm -2 biased at 2.1 V. The eletrolyzer works equally well both in deionized water and in regular tap water. This work demonstrates the opportunity of combining the advantages of different electrolyzer concepts for water splitting via cell architecture and materials design, opening pathways for sustainable hydrogen generation.

Catalysts are conventionally designed with a focus on enthalpic effects, manipulating the Arrhenius activation energy. This approach ignores the possibility of designing materials to control the entropic factors that determine the pre-exponential factor. Here we investigate a new method of designing supported Pt catalysts with varying degrees of molecular confinement at the active site. Combining these with fast and precise online measurements, we analyse the kinetics of a model reaction, the platinum-catalysed hydrolysis of ammonia borane. We control the environment around the Pt particles by erecting organophosphonic acid barriers of different heights and at different distances. This is done by first coating the particles with organothiols, then coating the surface with organophosphonic acids, and finally removing the thiols. The result is a set of catalysts with well-defined "empty areas" surrounding the active sites. Generating Arrhenius plots with >300 points each, we then compare the effects of each confinement scenario. We show experimentally that confining the reaction influences mainly the entropy part of the enthalpy/entropy trade-off, leaving the enthalpy unchanged. Furthermore, we find this entropy contribution is only relevant at very small distances (<3 Å for ammonia borane), where the "empty space" is of a similar size to the reactant molecule. This suggests that confinement effects observed over larger distances must be enthalpic in nature., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We discuss the latest developments in alternative battery systems based on sodium, magnesium, zinc and aluminum. In each case, we categorize the individual metals by the overarching cathode material type, focusing on the energy storage mechanism. Specifically, sodium-ion batteries are the closest in technology and chemistry to today's lithium-ion batteries. This lowers the technology transition barrier in the short term, but their low specific capacity creates a long-term problem. The lower reactivity of magnesium makes pure Mg metal anodes much safer than alkali ones. However, these are still reactive enough to be deactivated over time. Alloying magnesium with different metals can solve this problem. Combining this with different cathodes gives good specific capacities, but with a lower voltage (<1.3 V, compared with 3.8 V for Li-ion batteries). Zinc has the lowest theoretical specific capacity, but zinc metal anodes are so stable that they can be used without alterations. This results in comparable capacities to the other materials and can be immediately used in systems where weight is not a problem. Theoretically, aluminum is the most promising alternative, with its high specific capacity thanks to its three-electron redox reaction. However, the trade-off between stability and specific capacity is a problem. After analyzing each option separately, we compare them all via a political, economic, socio-cultural and technological (PEST) analysis. The review concludes with recommendations for future applications in the mobile and stationary power sectors.

Converting biomass into value-added chemicals holds the key to sustainable long-term carbon resource management. In this context, levulinic acid, which is easily obtained from cellulose, is valuable since it can be transformed into a variety of industrially relevant fine chemicals. Here we present a simple protocol for the selective esterification of levulinic acid using solid acid catalysts. Silica supported sulfonic acid catalysts operate under mild conditions and give good conversion and selectivity with stoichiometric amounts of alcohols. The sulfonic acid groups are tethered to the support using organic tethers. These tethers may help in preventing the deactivation of the active sites in the presence of water.

The connection between quantum size effects and the surface plasmon resonance of metal nanoclusters is introduced and the pros and cons of in situ and ex situ cluster analysis methods are outlined. A new method for estimating the size of nanoclusters is presented. This method combines core/shell cluster synthesis, UV-visible spectroscopy, and Mie theory. The core/shell approach enables the estimation of metal cluster sizes directly from the UV-visible spectra, even for transition metal nanoclusters such as Pd that have no distinct surface-plasmon peak in UV-visible region. Pd/Au and Au/Pd core/shell clusters as well as Au-Pd alloy clusters are synthesized and used as test cases for simulations and spectroscopic measurements. The results of the simulations and UV-visible spectroscopy experiments are validated with transmission electron microscopy.

The in situ combination of oxidative coupling of benzene to biphenyl and reductive coupling of chlorobenzene (also to biphenyl) using palladium catalysts (Pd(2+)/Pd(0)) is described. In each cycle, the reductive process regenerates the catalyst for the oxidative process and vice versa. Kinetic investigations show that the reaction rate depends on [C(6)H(6)], [C(6)H(6)Cl], and catalyst loading, with E(a)() = 13 kcal mol(-)(1). The reduced palladium catalyst undergoes deactivation through aggregation and precipitation, but it is observed that during this deactivation process the Pd(0) becomes an active catalyst for the reductive coupling of chlorobenzene. Accordingly, while Pd(0)/C particles are inactive, Pd(0) colloids do catalyze the tandem reaction. Conversion is increased in the presence of a phase-transfer catalyst, presumably due to stabilization of the active Pd(0) clusters. The two halves of the catalytic cycle are examined in the light of previous research, regarding analogous oxidative and reductive coupling reactions, using stoichiometric amounts of PdCl(2) and Pd(0), respectively. The roles of homogeneous PdCl(2) and Pd(0) clusters are discussed.