The improvement of catalytic processes is strongly related to the better performance of catalysts (higher conversion, selectivity, yield and stability). Additionally, the desired catalysts should meet the requirements of being low cost as well as environmentally and user-friendly. All these requirements can only be met by catalyst development and optimisation following new approaches in design and synthesis. This article discusses three major approaches in the design and development of catalysts: (a) high-throughput synthesis; (b) reaction kinetic studies; (c) in situ and operando spectroscopy for studying catalysts under process conditions. In contrast to approaches based on high-throughput synthesis and reaction kinetic studies, an emerging approach of studying catalysts under process conditions using in situ and operando spectroscopy and transferring the gained knowledge to design of new catalysts or the optimisation of existing catalysts is not yet widely employed in the chemical industry. In this article, examples of using in situ or operando spectroscopy for studying the surface and bulk of catalysts under process conditions are discussed, with an overview of applying in situ X-ray absorption spectroscopy (XAS), in situ infrared (IR) spectroscopy and in situ near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) for monitoring the bulk and surface composition of PdZn/ZnO and Pd₂Ga/Ga₂O₃ methanol steam reforming catalysts.

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Stress whitening is a long-standing problem and scientific work has focused on evaluating causes of this in bulk polymer systems. In this paper we focus on this optical defect exhibited by a complex thermosetting polyester melamine coating system used extensively in the pre-coated metal industry. There are several mechanisms proposed for how stress whitening occurs and hence there is uncertainty over the causes in the systems mentioned. The most likely explanation given to date is that a number of proposed micro-mechanisms exist, which one is occurring is entirely dependent on the system being investigated. The work presented shows that the presence of dissimilar particles is the cause of the stress whitening. The proposed mechanism for whitening and its disappearance in this case is a time and temperature dependent change in density, i.e. cracking or voiding, where the cracks are outside the range that scatters light with an increase in temperature.

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Rising earth temperatures are causing chaos and we need to act now. A new International Standard helps governments and industry take action towards reducing the damage.

Despite considerable research efforts, finding a chemically stable electrolyte mixture in the presence of reduced oxygen species remains a great challenge. Previously, dimethyl sulfoxide (DMSO) and sulfolane (tetramethylene sulfone (TMS))-based electrolytes were reported to be stable for lithium air (Li-O₂) battery applications. Recently lithium hydroxide (LiOH) based chemistries have been demonstrated to involve supressed side reactions in water-added ether- and DMSO-based electrolytes. Herein, we investigate the impact of DMSO-based electrolyte and sulfolane co-solvent on cell chemistry in the presence of water. We found that DMSO-based electrolyte leads to formation of a peroxide-hydroxide mixture as discharge products and the removal of both LiOH and lithium peroxide (Li₂O₂) on charging from 3.2–3.6 V (vs. Li⁺/Li) is observed. In the presence of sulfolane as co-solvent, a mixture of Li₂O₂ and LiOH is formed as major discharge products with slightly more LiOH formation than in the absence of sulfolane. The presence of sulfolane has also significant effects on the charging behaviour, exhibiting a clearer 3 e⁻/O₂ oxygen evolution reaction profile during the entire charging process. This work provides insights into understanding the effects of the primary solvent on promoting LiOH formation and decomposition in lithium iodide (LiI) mediated non-aqueous Li-O₂ batteries.

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Each year, millions of lives are adversely affected by smoke released from cooking on open fires or simple stoves fuelled by wood, charcoal and dung. The much-awaited series of international guidelines…

Introduction “Atomic Layer Deposition in Energy Conversion Applications” is a series of reviews presented as nine chapters that focus on the applications of atomic layer deposition (ALD) for photovoltaics, electrochemical energy storage and photo- and electrochemical devices. These have been edited by Julien Bachmann whose research is based on the fabrication of nanostructured materials and…

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With over two hundred diseases spread through the food chain, it’s clear that safe, sustainable food production is one of our greatest challenges. Globalization of the food trade further complicates food…

Agricultural products are the base of the Nigerian economy, supplying food for the Nigerian people as well as valuable cash crops for export to other countries. These days, the agricultural sector is developing…

As Quality Manager at KMC, the Danish-based food ingredients company, Marianne Dam is responsible for the maintenance and updating of KMC quality systems and certifications. Here, she explains how ISO…

Can we trust current food security systems and are they sustainable? Some of the specialists involved in the revision of ISO 22000 explain why the new version of the standard is a timely response, for…