Introduction American Chemical Society National Meetings and Expositions are held twice a year in spring and autumn and constitute the largest gathering of chemical scientists at any point in the conference calendar. This year the 247th meeting (1) was held from 16th–20th March 2014, hosted at the Dallas Convention Centre, Texas, USA. The overarching theme of the conference was Chemistry...
This event, hosted by the Royal Society of Chemistry, was held at Burlington House, London, UK, on 23rd November 2017. There was a good attendance with 55 delegates from academia and industry, mainly from the UK. A brief overview of some of the presentations is described here to give a flavour of recent progress in this area. The first session was called ‘Control of Pickering Emulsions’....
Professor Binks’ research is primarily concerned with materials chemistry. He is a physical chemist with research interests in surfactants, foams, emulsions and colloidal particles at interfaces. His work looks at the fundamental science that underpins the behaviour of formulations. As such, it has implications for industry applications in areas as diverse as food, cosmetics, oil and gas,...
“Particle-Stabilized Emulsions and Colloids: Formation and Applications”, edited by To Ngai and Stefan A. F. Bon, is the third book of the Royal Society of Chemistry (RSC) Soft Matter Series, published in 2015. Both editors have extensive expertise in polymer chemistry and its application to colloid science. Professor Ngai's research interests focus on interparticle interactions at fluid...
The accurate and precise characterisation of disordered, mesoporous solids continues to be an ongoing challenge due to the high level of complexity of such materials. Common, indirect methods, such as gas sorption and mercury porosimetry, still offer relatively cheap, and, most importantly, statistically representative characterisations of macroscopic samples. This work reviews and expands upon recent developments aimed at increasing, and cross-validating, the information obtained from such methods. This involves developing a better understanding of the pore-pore co-operative effects that emerge only in extensive, disordered pore networks to better interpret raw characterisation data, and to use these effects to deliver more information on the void space. This work also describes novel hybrid methods that also greatly increase the information that indirect methods can deliver on complex mesoporous solids.
Introduction The meeting was held at the National Physical Laboratory, Teddington, UK, on 9th and 10th October 2018. This was the fourth such meeting, with the general aim of bridging the so-called ‘valley of death’ in translating research on graphene into meaningful products. The speakers were primarily academics and those from companies manufacturing graphene. One or two manufacturers of...
This study focuses on new technologies for the production of medical implants using a combination of robotics and microplasma coatings. This involves robot assisted microplasma spraying (MPS) of a multilayer surface structure on a biomedical implant. The robot motion design provides a consistent and customised plasma coating operation. Based on the analytical model results, certain spraying modes were chosen to form the optimised composition and structure of the titanium/hydroxyapatite (HA) multilayer coatings. It is desirable that the Ti coated lower layer offer a dense layer to provide the implant with suitable structural integrity and the Ti porous layer and HA top layer present biocompatible layers which are suitable for implant and tissue integration. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to analyse the structure of the coatings. The new robot assisted MPS technique resulting from this research provides a promising solution for medical implant technology.
Ceramics are traditionally sintered at high temperatures (~80% melting temperature (Tm)). There are numerous incentives to reduce processing temperature: the reduction in processing energy; integration of polymeric and non-noble metals; greater control of microstructure and final component geometries. ‘Cold sintering’ has been developed as a novel method of densification which uses a transient liquid phase, pressure and heat to achieve dense ceramics. This review explores the process of cold sintering and its potential to densify various ceramic materials and components at low temperatures (<300°C), primarily describing recent results at The University of Sheffield, UK.
Introduction Into my hands came an exciting new book about space. “Spacecraft Thermal Control Technologies” is written by Professor Jianyin Miao, Qi Zhong, Professor Qiwei Zhao and Professor Xin Zhao. All the authors of this book are part of the Institute of Spacecraft System Engineering, China Academy of Space Technology (CAST), Beijing, China. Jianyin Miao is a head scientist of heat...
Platinum-based alloys are being developed for high-temperature applications with the aim of replacing some of the currently used nickel-based superalloys (NBSAs) and benchmark alloy, PM2000. The platinum-based superalloys have a similar structure to the NBSAs and can potentially be used at higher temperatures and in more aggressive environments because platinum is more chemically inert and has a higher melting point. In this paper, the recent progress in research and development of platinum-based superalloys is overviewed. Firstly, the composition optimisation and structural design of platinum-base superalloys are introduced. The structural characteristics, mechanical properties, oxidation resistance and corrosion behaviour of platinum-aluminium ternary, quaternary and multiple superalloys are summarised. Finally, directions for further research and application of platinum-based superalloys are analysed and prospected.
The present article reviews the synthesis routes and applications of platinum-based nanoparticles in emerging fields such as energy harvesting, health care applications and sensors. Increasingly, more useful, novel and multifunctional materials are needed with fewer side effects. This article provides an overview of Pt-based nanoparticles along with recent applications in electrochemistry, photochemistry, biosensors and gas sensors. In particular, platinum dioxide (Adams’ catalyst) has been used in many chemical reactions including hydrogenation, oxidation and reduction.
This paper overviews the fabrication, microstructural characteristics, mechanical properties and tribological behaviour of B4C reinforced aluminium metal matrix composites (AMMCs). The stir casting procedure and parameters used to fabricate the Al-B4C composites are discussed. The influence of physical parameters such as applied load, sliding speed and sliding distance on tribological behaviour is analysed. The role of the mechanically mixed layer (MML) and wear mechanisms on the wear behaviour and friction coefficient are emphasised. The overview of tribological behaviour revealed that the Al-B4C composites possess excellent abrasion resistance and the ability to operate over a wide range of physical parameters. The Al-B4C composites exhibited better tribological behaviour when compared with the composites reinforced with conventional reinforcement particles (SiC).
In the present study polyvinylpyrrolidone (PVP) stabilised copper/palladium bimetallic nanoclusters were synthesised through chemical routes. The prepared Cu/Pd bimetallic nanoparticles were characterised by ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The UV-vis absorbance band confirmed the formation of complex metal ions triggered by the complexing agent trisodium citrate. The XRD pattern indicated the formation of bimetallic nanoparticles. The TEM images of the synthesised bimetallic Cu/Pd nanoparticles showed that the size distribution of the particles was in the range 5–15 nm. An acoustic particle sizer was then used to analyse the size distribution. The results obtained by the acoustic particle sizer were consistent with the XRD and TEM analyses. These results demonstrate the potential usefulness of the acoustic particle sizer for quick and easy characterisation of nanoparticles in various catalytic, sensor and fuel cell applications.
To evaluate future applications of metallic clusters in nanoscience and nanotechnology, the electronic properties of the high-nuclearity carbonyl anionic platinum cluster [Pt19(CO)22]4– were investigated using two different organic cations. In particular, N,N'-diethyl viologen dication (Vio2+) and N,N'-dimethyl-9,9'-bis-acridinium dication (Acr2+) were employed as counterions, oxidising agents and characterisation probes. The reactions of [Pt19(CO)22]4– tetra-n-butylammonium salt, (TBA+)4([Pt19(CO)22]4–), with both (Vio2+) and (Acr2+), used as tetraphenylborate salts, yielded two new compounds, which were isolated. The stoichiometries and properties of these new compounds were determined and compared on the basis of infrared (IR) solution spectra, electron spin resonance (ESR) analyses, fluorometric spectra, superconducting quantum interference device (SQUID) magnetometry and resistivity measurements. For Vio2+, a cation-exchange reaction produced the final compound (Vio2+)2([Pt19(CO)22]4–), ‘PtVio’, which was structurally characterised by single crystal X-ray diffraction (XRD) analysis. However, when using Acr2+, a spontaneous redox reaction occurred and a (Acr+)(TBA+)2([Pt19(CO)22]3–) stoichiometry for the precipitated solid, ‘PtAcr’, was inferred from the experimental evidence, leading to an interesting ‘doubly-radicalic salt’. This new type of salt, consisting of a radical anionic Pt cluster and a radical cation, is characterised by extremely simple synthesis and isolation processes and by the lowest solid-state resistivity found in high-nuclearity cluster salts with redox-active cations (1).
“Metal-Organic Frameworks: A New Class of Crystalline Porous Materials” published by Lambert Academic Publishing, 2014, is a book written by Dr Behnam Seyyedi on the emerging porous materials of metal-organic frameworks (MOFs). The term MOF was coined by Omar Yaghi in 1995 (1). MOFs consist of both organic and inorganic building entities, where the organic ligands, i.e. spacers, are coordinated to the metal ion clusters, i.e. nodes, to create extended frameworks. In some cases, the frameworks are rigid enough to form internal voids after solvent removal, forming structures with high porosity and surface areas (up to ~ 7000 m2 g–1). MOFs have shown potential applications in a wide range of fields, such as gas separation and storage, catalysis, sensing and drug delivery.
Materials chemistry is concerned with establishing connections between structure, properties, processability and performance of molecular materials, including organic compounds and polymers, supramolecular architectures and nanoporous substances. Encompassed within this diverse field are molecular magnets, graphene, optoelectronic devices, artificial photosynthesis, chemical sensors, speciality polymers, fluorescent labels, functional membranes, composite conjugated hybrids and molecular sieves. The field relies heavily on sophisticated organic synthesis but readily embraces computational chemistry in order to delve more deeply into the properties of the materials. The topic provides an important interface between atomic, molecular and supramolecular behaviour and the functions of the substance under examination. All manner of molecular materials are considered, ranging from thin films to organogels to solids with microscopic cavities. The 12th International Conference on Materials Chemistry was held between 20th–23rd July 2015 at the University of York, UK, and covered the full range of topics, with six plenary lectures supported by twenty-four keynote lectures and over a hundred invited or contributed talks (1). In addition, some 370 posters were presented. The conference was co-chaired by Duncan Bruce (University of York) and Dermot O'Hare (University of Oxford, UK).
Introduction “Hierarchical Nanostructures for Energy Devices” is part of the Royal Society of Chemistry Nanoscience & Nanotechnology Series. The editors Seung Hwan Ko and Costas P. Grigoropoulos have published more than 60 articles together with a strong focus on laser processing of nanomaterials and hierarchical surface coatings. This book highlights the advantages of hierarchical...
Aqueous suspensions of multi-walled carbon nanotubes (MWCNTs + deionised water) have been synthesised. Carbon nanotubes (CNTs) were derived by chemical vapour deposition (CVD). Transmission electron microscopy (TEM) measurements show the formation of MWCNTs. Three samples of CNT-based aqueous nanofluids having MWCNT concentrations of 0.01 vol%, 0.03 vol% and 0.05 vol% were prepared with the help of ultrasonic irradiation. A very small amount of sodium dodecyl sulfate (SDS) was used as a surfactant to minimise the agglomeration of the MWCNTs. An effective enhancement in thermal conductivity was observed at different temperatures. The obtained results are explained with percolation theory.
Introduction Faraday Discussions are unique international meetings that focus on miscellaneous areas of chemistry and have been held for over 100 years. The format of these meetings is distinctive because delegates submit their papers in advance and these are distributed to all the participants prior to the meeting. During the meeting, the presenting authors are given five minutes to...
Johnson Matthey has a long history and track record of designing and supplying specialist coatings into a wide range of application areas and substrate types. A common theme is the requirement to deposit precise amounts of materials. This is key for expensive platinum group metals and for the resulting coating to provide a function such as catalytic, conductive, protective or optical....
