Spectroscopy case studies

Improving catalysts to provide greener emissions

The hunt for viable green alternatives to traditional petrol and diesel engines has led a move towards natural gas engines, which produce less carbon dioxide emissions.

But natural gas engines pose other problems due to unburnt methane (a potent greenhouse gas) in the exhaust feed. So scientists at Diamond, Johnson Matthey – a global leader in sustainable technologies - and the University of Reading, have been researching ways to improve catalysts to convert residual methane into more environmentally friendly products.

A multi-technique approach to study the properties of ZnO under industrial conditions

Zinc oxide (ZnO) is a highly desirable multifunctional material possessing superior electronic, structural and morphological properties which also exhibits high chemical stability, a broad range of radiation absorption and high photostability. For this reason, ZnO is used in n-type semiconductors, solar cells, photocatalysts, sensing materials and antiseptic additive compounds. 

Many believe that the defects present in ZnO’s structure are a key factor in influencing aspects of its performance and control of specific defect types could be used to enhance its functionality.

The essential trace mineral, selenium, is of fundamental importance to human health. It plays an important role in many biological processes such as guarding against oxidants, the formation of thyroid hormones, DNA synthesis, fertility and reproduction.

At present, insufficient levels of Se in the diet affects up to 14% of the population worldwide, bringing with it the associated risk of developing chronic degenerative diseases.

Plants can transform naturally occurring inorganic Se species (present in soil) into organic Se species – the desired form of selenium in the human diet. Effectively, the Se level in soil usually has a direct influence on the concentration of Se present in food and subsequently in the human body. However, high Se concentration in soil induces stress in the plant and may hamper its normal development.

The effects of mine tailings dam failures on local ecosystems

On 4th August 2014, the Mount Polley mine tailings dam failed, resulting in 25 million m³ of material discharged into the surrounding area, the second-largest failure by volume on record.

Mine tailings dam failures of this kind can rapidly add large volumes of vanadium (V)-bearing solid and liquid waste to the fluvial environment, with both short and long-term effects on the local ecosystems.

Measuring nanoparticle penetration into the skin using a new sunscreen formula

For many years, the skin care industry has been challenged with providing sun protection for its users whilst being environmentally friendly and both easy and safe to use. 

Many existing products on the market use nanoparticles containing zinc oxide and titanium dioxide. These have been known to provide a transparent coating when used in formulations spread onto the skin’s surface. This transparency provides an aesthetically pleasing result, not achievable with larger-particle formulations. However, the potential for solid nanoparticles to penetrate and to diffuse into the body raises a considerable health and safety issue. There has therefore been a drive for research in this area, to develop alternative solutions.

Increasing fuel efficiency whilst retaining reactor safety

To be fully effective, the cladding encapsulating nuclear fuel
must be highly resistant to radiation damage, be relatively
transparent to thermal neutrons, have effective corrosion
resistance and good mechanical properties. Zirconium alloys are well suited to these needs and have therefore to date been the most favoured material for fuel cladding. Commonly used alloys such as Zircaloy-2, Zircaloy-4, M5TM and ZIRLOTM also include small amounts of iron which has been shown to increase corrosion resistance.

High-performance, low cost materials for electronic devices

Transparent conducting films are an important component of modern life, providing optically transparent and electrically conductive material for a wide range of devices, such as smart phones, touchscreens and solar panels. The field’s most widely used material is tin-doped In₂O₃ (ITO), accounting for 60% of both global indium use and the transparent conductor market. However, indium is expensive, so there is strong demand for a cheaper alternative or a way to use less indium.  

A Newton Fund collaboration for the Thai food industry

The diet in Thailand has traditionally consisted of vegetables, pork, chicken and fish, and many Thais are avid meat lovers. Recently, however, there has been a move towards healthier alternatives to meat, providing a challenge for the food industry to maintain the desired flavour and experience of eating meat, whilst turning to more plant-based sources.

Designing an effective catalyst to convert palm oil waste into sustainable biofuels

Indonesia is one of the largest suppliers of palm oil in the world, producing 42 million tonnes in 2018¹. It is also experiencing an increase in car usage, coupled with a growth in imports of fuel.

To overcome this problem, the Indonesian government is driving a move to biofuels. Until recently the fresh fruit bunch from palm oil has successfully been used, however the empty fruit bunch (EFB) and palm kernel shell (PKS) provide a more sustainable source of lignocellulose, a key component in second generation biofuel production.

One prospective method for the biofuel production is conversion of lignocellulose into bio-oil via fast pyrolysis and then upgrading the bio-oil over a catalyst, to remove oxygen. However, the existing alumina-based and noble metal catalysts still suffer from catalyst deactivation due to carbon deposition and metal leaching.

Recycling carbon dioxide and powering the chemical reactions with renewable energy.

Over recent years we have seen a global move towards renewable energy not only to support increased demand for energy but also to reduce the production of carbon dioxide, a common pollutant from burning fossil fuels. Engineers and scientists are continually looking at ways to store this energy during periods of low user consumption (day-time) and to maximise its usage during periods of high demand (evening-time).

XAS studies of titanium dioxide thin films for memory applications

Titanium dioxide is one of the most widely used metal oxides and in recent years it has attracted increasing attention in the form of thin films for applications in microelectronics. In particular, it has found potential application in resistive random access memory (RRAM) cells, where the titanium dioxide active layer is sandwiched between two metal electrodes in a metal-insulator-metal (MIM) device architecture. Because of their simple structure, RRAM cells, also known as memristors, can be incorporated into devices with high density that function at low power and high speed. The importance of RRAM devices is due to the fact that they exhibit resistive switching; i.e., they have the ability to toggle their corresponding resistance between high and low resistance states by application of an appropriate voltage. However, this resistive switching mechanism is not currently well understood and is still a matter of debate.

Chemical tomography: world first in catalysis research

In the chemical industry and industrial research, catalysis plays a vital role. Catalysts are in constant development to fulfil economic, political and environmental demands. Gaining valuable new information about the atomicnanoscale chemical structure, coupled with information about the micro-distribution of such species, has applications across a wide range of disciplines such as materials, biomedical, environmental, and geophysical sciences.

Understanding the Charging Mechanism of Lithium-Sulfur Batteries Using Spatially Resolved Operando X-Ray Absorption Spectroscopy

In today’s battle against climate change, replacement of conventional cars with battery electric vehicles (BEV) offers an opportunity to significantly reduce future carbon dioxide emissions. Currently, BEVs employ lithium-ion batteries which are expensive to produce and have significant drawbacks; their safety and limited transport being the main issues. Significant interest is therefore being shown in replacing these lithium-ion batteries with a lithium-sulfur battery (LiS or Li₂S/Si), which operates using a cheap and abundant raw material with about a two-fold higher specific energy compared to lithium-ion batteries.

Spectroscopic studies on anticancer therapy gallium

Gallium (Ga) based salts show very promising anticancer properties. However, the maindrawbacks of therapy with Ga salts is the need for slow, long-term infusion to avoid the toxicities associated with high plasma levels of Ga, and the poor bioavailability when the drug is dosed via the oral route.

Reducing wear and tear with effective lubricants

Effective lubrication has a significant impact on a number of applications ranging from human artificial joint implants to energy efficiency of internal combustion engines and the reliability of offshore wind turbine gearboxes. At low running speeds and high contact pressures the fluid film cannot be maintained and therefore effective lubrication is greatly influenced by the presence of chemical additives in the lubricant. These additives interact with the lubricated surfaces to form nanoscale tribofilms that reduce both material wear and energy losses due to friction. Understanding the mechanisms by which these tribofilms form is essential for development and optimisation of the next generation environmentally friendly effective lubricants, materials and tribological systems.

Nano-scale processes in radwaste management

Management and disposal of higher activity radioactive wastes is a significant issue across the developed world as many countries with a history of nuclear power generation and military activities seek long term solutions for these materials. The most common disposal choice is containment within a deep geological disposal facility (GDF). To remain effective over the long term, the design of a GDF must limit the mobility and migration of radionuclides.

Looking at platinum speciation in three way catalysts

Platinum group metals play a crucial role in a variety of applications and in particular for a host of catalytic applications.  The largest application is currently in vehicle emission control (VEC) catalysts to efficiently reduce particulate matter, CO, NOx and hydrocarbons.  This type of catalytic system is diverse and complex and generally contains 0.1-1 wt% active metal deposited on a thermally stable structural support.  Therefore, applying a wide range of techniques is essential to fully understand these complex catalytic materials.

Keele University research provides iron clue in Alzheimer's Disease

By 2021, a million people in the UK will have dementia and yet the cause of the condition is still unknown. Alzheimer’s disease (AD) is a fatal age-related neurodegenerative disorder characterised by extensive neuronal loss in the higher brain centres, resulting in cognitive decline, memory loss and psychosis. It has been suggested that areas of AD pathology are corresponding to the increased concentrations of brain iron and the toxic form of iron builds up in the same location as the brain lesions caused by Alzheimer’s disease. 

Sasol uses microreactor sample environment for catalysis research

A proper understanding of structure-property relationships plays a central role in the design and discovery of novel materials. In many cases, exploring the relationship between the structure of a new material and its physical and chemical properties requires that measurements are carried out under exactly the same in situ conditions of temperature, pressure and atmosphere as the performance environments of the material of interest.

Pitting corrosion – looking into industrial processes using time-resolved in situ studies

”Corrosion resistant” metals are used in challenging environments and where safety is critical, such as in pipelines, aircraft and nuclear waste storage vessels. But it is precisely these materials that are vulnerable to a form of corrosion known as pitting. Understanding of the mechanisms by which these pits form and propagate may allow engineers to build more accurate models of corrosion to predict the lifetime of components and plan when they need inspecting or replacing.

Methanol production from biomass

Catalytic production of methanol is an industrially important process and this high-energy density liquid is widely used in the manufacture of plastics and synthetic fibres, and in fuel cells. Currently, methanol is synthesized on a large scale using natural gas from an energy-inefficient process, which requires an endothermic, and therefore thermally intensive, step to completely break down the methane to CO/H₂ before methanol can be formed. Scientists from the University of Oxford were keen to explore an alternative non-syn-gas route for methanol production utilising ethylene glycol (EG) which can be sourced from biomass.

Fe-based materials for Li ion batteries

Diminishing supplies of fossil fuels, together with the desire to reduce greenhouse gas emissions, has propelled electrochemical storage to the forefront of modern research. In particular, Li-ion batteries have empowered consumer electronic devices and are now seen as having great potential for use in (hybrid)-electricvehicles, where high power densities are essential. In the search for new positive electrodes to meet this demand, there has been a focus on polyanionic compounds and how they can be manipulated to control the voltage of the transition metal redox couple.

Study of metal distribution and speciation in human tissues

Since 1996, approximately 1.5m patients have had metal-on-metal (MOM) hip replacements worldwide. This technology has been shown to work well in the medium term, even for highly active patients; however, young patients require this device to operate for up to 50 years. Significantly, in up to 10% of patients the implant has to be removed prematurely, within five years of implantation. Therefore, a better understanding of the mechanism of failure is needed to develop fully biocompatible implants, for which there has been a predicted soaring demand over the next twenty years.

Elemental mapping of wheat grain

Deficiencies in iron and zinc are affecting an increasing number of people worldwide due to the low intake and bioavailability of minerals from traditional diets based with little or no meat, fruit and vegetables. The problem is particularly serious in Africa, the eastern Mediterranean and south-east Asia where a variety of chronic health problems are related to low mineral intake.