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Propane dehydrogenation (PDH), an important process for propylene synthesis, relies on expensive noble metals or highly toxic oxides as catalysts. In a recent publication, Gong and co-workers report a breakthrough discovery for PDH by introducing a sustainable catalyst composed of titanium oxide overlayers encapsulating nickel nanoparticles, termed Ni@TiO x . This innovative catalyst showcases exceptional performance in PDH, exhibiting high propylene selectivity and stability under industrially relevant conditions. The study elucidates the role of defective TiO x overlayers and the electronic promotional effect of subsurface Ni in enhancing catalytic activity, translating a traditional model catalyst system into a sustainable industrial catalyst for low-carbon energy and the chemical industry., (© 2024 Wiley-VCH GmbH.)

Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 e - -pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns including catalyst degradation due to Fenton reaction or poor efficiency of H 2 O 2 electrosynthesis. Herein we show that the generally accepted ORR electrocatalyst design based on a Sabatier volcano plot argument optimises activity but is unable to account for the 2 e - -pathway selectivity. Through electrochemical and operando spectroscopic studies on a series of CoN x /carbon nanotube hybrids, a construction-driven approach based on an extended "dynamic active site saturation" model that aims to create the maximum number of 2 e - ORR sites by directing the secondary ORR electron transfer towards the 2 e - intermediate is proven to be attainable by manipulating O 2 hydrogenation kinetics., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Catalysis is involved in around 85 % of manufacturing industry and contributes an estimated 25 % to the global domestic product, with the majority of the processes relying on heterogeneous catalysis. Despite the importance in different global segments, the fundamental understanding of heterogeneously catalysed processes lags substantially behind that achieved in other fields. The newly established Max Planck-Cardiff Centre on the Fundamentals of Heterogeneous Catalysis (FUNCAT) targets innovative concepts that could contribute to the scientific developments needed in the research field to achieve net zero greenhouse gas emissions in the chemical industries. This Viewpoint Article presents some of our research activities and visions on the current and future challenges of heterogeneous catalysis regarding green industry and the circular economy by focusing explicitly on critical processes. Namely, hydrogen production, ammonia synthesis, and carbon dioxide reduction, along with new aspects of acetylene chemistry., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Gold (Au) on ceria-zirconia is one of the most active catalysts for the low-temperature water-gas shift reaction (LTS), a key stage of upgrading H 2 reformate streams for fuel cells. However, this catalyst rapidly deactivates on-stream and the deactivation mechanism remains unclear. Using stop-start scanning transmission electron microscopy to follow the exact same area of the sample at different stages of the LTS reaction, as well as complementary X-ray photoelectron spectroscopy, we observed the activation and deactivation of the catalyst at various stages. During the heating of the catalyst to reaction temperature, we observed the formation of small Au nanoparticles (NPs; 1-2 nm) from subnanometer Au species. These NPs were then seen to agglomerate further over 48 h on-stream, and most rapidly in the first 5 h when the highest rate of deactivation was observed. These findings suggest that the primary deactivation process consists of the loss of active sites through the agglomeration and possible dewetting of Au NPs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The direct synthesis of hydrogen peroxide offers a potentially green route to the production of this important commodity chemical. Early studies showed that Pd is a suitable catalyst, but recent work indicated that the addition of Au enhances the activity and selectivity significantly. The addition of a third metal using impregnation as a facile preparation method was thus investigated. The addition of a small amount of Pt to a CeO2-supported AuPd (weight ratio of 1:1) catalyst significantly enhanced the activity in the direct synthesis of H2O2 and decreased the non-desired over-hydrogenation and decomposition reactions. The addition of Pt to the AuPd nanoparticles influenced the surface composition, thus leading to the marked effects that were observed on the catalytic formation of hydrogen peroxide. In addition, an experimental approach that can help to identify the optimal nominal ternary alloy compositions for this reaction is demonstrated., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Today hydrogen peroxide is produced by an indirect process in which an alkyl anthraquinone is sequentially hydrogenated and oxidized. In this way hydrogen and oxygen are kept separate during the manufacturing process. A process where molecular oxygen is directly hydrogenated could be preferred if control of the sequential hydrogenation can be achieved, particularly if high rates can be attained under intrinsically safe, non-explosive conditions. Herein we describe recent progress in the direct synthesis of hydrogen peroxide using supported palladium and gold-palladium alloy catalysts and consider some of the problems that have to be overcome.

Catalysis by gold has rapidly become a hot topic in chemistry, with a new discovery being made almost every week. Gold is equally effective as a heterogeneous or a homogeneous catalyst and in this Review we attempt to marry these two facets to demonstrate this new found and general efficacy of gold. The latest discoveries are placed within a historical context, but the main thrust is to highlight the new catalytic possibilities that gold-catalyzed reactions currently offer the synthetic chemist, in particular in redox reactions and nucleophilic additions to pi systems. Indeed gold has proved to be an effective catalyst for many reactions for which a catalyst had not been previously identified, and many new discoveries are still expected.