Angew Chem Int Ed Engl
February 2025
While the outstanding stability of per- and polyfluoroalkyl substances (PFAS) paved the way for their widespread application in a huge variety of applications, it also resulted in their nickname "forever chemicals". The rising awareness for PFAS-related environmental and health concerns drives a discussion on the most effective ways to abate PFAS emissions into the environment, i.e.
View Article and Find Full Text PDFThe use of visible photon fluxes to influence catalytic reactions on metal nanoparticle surfaces has attracted attention based on observations of reaction mechanisms and selectivity not observed under equilibrium heating. These observations suggest that photon fluxes can selectively impact the rates of certain elementary steps, creating nonequilibrium energy distributions among various reaction pathways. However, quantitative studies validating these hypotheses on metal nanoparticle surfaces are lacking.
View Article and Find Full Text PDFThe activity and durability of the Cu/ZnO/AlO (CZA) catalyst formulation for methanol synthesis from CO/CO/H feeds far exceed the sum of its individual components. As such, this ternary catalytic system is a prime example of synergy in catalysis, one that has been employed for the large scale commercial production of methanol since its inception in the mid 1960s with precious little alteration to its original formulation. Methanol is a key building block of the chemical industry.
View Article and Find Full Text PDFPlatinum nanoparticles (NPs) supported by titania exhibit a strong metal-support interaction (SMSI) that can induce overlayer formation and encapsulation of the NP's with a thin layer of support material. This encapsulation modifies the catalyst's properties, such as increasing its chemoselectivity and stabilizing it against sintering. Encapsulation is typically induced during high-temperature reductive activation and can be reversed through oxidative treatments.
View Article and Find Full Text PDFHydrogen spillover from metal nanoparticles to oxides is an essential process in hydrogenation catalysis and other applications such as hydrogen storage. It is important to understand how far this process is reaching over the surface of the oxide. Here, we present a combination of advanced sample fabrication of a model system and in situ X-ray photoelectron spectroscopy to disentangle local and far-reaching effects of hydrogen spillover in a platinum-ceria catalyst.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
October 2022
Oxides are essential catalysts and supports for noble metal catalysts. Their interaction with hydrogen enables, e.g.
View Article and Find Full Text PDFThe copper-zinc-alumina (CZA) catalyst is one of the most important catalysts. Nevertheless, understanding of the complex CZA structure is still limited and hampers further optimization. Critical to the production of a highly active and stable catalyst are optimal start-up procedures in hydrogen.
View Article and Find Full Text PDFHeterogeneous catalysts play a pivotal role in the chemical industry. The strong metal-support interaction (SMSI), which affects the catalytic activity, is a phenomenon researched for decades. However, detailed mechanistic understanding on real catalytic systems is lacking.
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