A large collaboration led by researchers from the University of Wollongong has used the Australian Synchrotron to investigate a promising carbon coated cathode material for rechargeable sodium ion batteries that had a very long life.

The research demonstrated that  a new compound, an iron-based pyrophosphate-based sodium composite, could compete with other iron-based cathode materials for large scale applications, such as wind and solar storage, because  its charge retention capacity was close to 90 per cent after 1100 cycles at 5 C.

 

Low energy density, sluggish sodium kinetics and poor cycling stability have been the main barriers to the widespread use of sodium ion batteries as less costly alternative to lithium batteries.

The synchrotron was used to investigate the electrochemical mechanism at work in a new cathode material, Na3.32Fe 2.34 (P2O7) as reported in Advanced Materials.

The multiple anions of the new compounds give them high structural and thermal stability with only small volume changes in the unit cell.

Qinfen Gu, a senior scientist on the powder diffraction beamline, said it was possible to charge and discharge the battery in real time while sending X-rays through the nanoparticles, which revealed what was happening at a structural level in the cathode material during cycling.


The diffraction data indicated a single phase transition during charge and discharge, which helped explain its superior electrical performance.

A reversible electrochemical reaction, suggested by continuous lattice breathing, also took place in the material.

“The movement of the sodium ions can cause the cathode to expand or contract, which can degrade the material and interfere with the movement of electrons,” said Gu.

In this case the researchers noted that only a small change in lattice parameters and unit cell offered strong support for the stability of the structure during cycling.

The application of a carbon coating on the cathode material improved its thermal and structural stability, enhanced its electrical conductivity and contributed to a high rate capacity. 

The investigators also attributed superior electrochemical performance to a dramatic increase in the transfer rate of electrons across different layers of the material and an acceleration of the transfer of sodium ions by the uniform amorphous carbon layer.

Experiments confirmed that without the carbon coating, the material degrades very quickly and after 500 cycles, charge retention capacity drops.

“The electrolyte attacks the cathode material and the carbon coating slows this down,” explained Gu.

The material would be low cost because it is primarily composed of ample elements, sodium and iron, and offers improved safety.

 Other collaborating institutions included the University of South China, the University of Queensland and Sichuan University (China). 

http://dx.doi.org/10.1002/adma.201605535

ANSTO has secured $80.2 million in new funding to expand the research capabilities of the Australian Synchrotron. 

The funding boost was made by the New Zealand Synchrotron Group Limited (representing funding from the New Zealand Government and 10 New Zealand universities and research institutions), the Defence Science and Technology Group and 19 universities and medical research institutes across Australia. 

The new funding will expand the number of beamlines at the Synchrotron from 10 to as many as 18, increasing research output at the facility and helping keep up with significant researcher demand for the state-of-the-art facility.

The first stage of the expansion will see the construction of the Micro-computed Tomography (MCT) beamline and the Medium Energy XAS (MEX) beamline: 

•        The MCT beamline will complement the Imaging and Medical Beamline (IMBL), by allowing 3D structures to be studied in close detail, which will enable advanced research in the fields of biological and health sciences.

•        The MEX beamline will enable mapping of lighter elements such as sulphur, phosphorous, chlorine, calcium and potassium, with applications across sectors including aiding in the development of cancer treatment.

These beamlines will be closely followed by a Small Angle X-ray Scattering (BioSAXS) beamline. Supported by the New Zealand Synchrotron Group’s significant $25 million investment, the beamline will allow for detailed protein studies focussed on improving drug design and validation processes. 

Minister for Industry, Innovation and Science, Senator the Hon Arthur Sinodinos, welcomed the funding for the beamline expansion, which will be supported by the Australian Government’s significant operational investment made via the National Innovation and Science Agenda (NISA).

The NISA provides $520 million in operational funding to the Australian Synchrotron, which includes operational funding for the new beamlines.

Minister Sinodinos said the scale of the contributions highlighted the extremely significant role the Synchrotron plays in Australia’s science and innovation ecosystem. 

“The Australian Synchrotron is one of our most important pieces of landmark research infrastructure, which on a daily basis delivers practical benefits across a variety of vital areas,” Minister Sinodinos said.

“This is applied science at its best, with applications for medical researchers, the environment and industry.

“The Australian Government welcomes this new investment to expand capacity at the Synchrotron, which will be supported by our significant operational investment made via the National Innovation and Science Agenda (NISA).”

ANSTO CEO, Dr Adi Paterson, said this was the latest ANSTO collaboration that provides new opportunities for industry and researchers. 

“ANSTO has been working to secure more than $100 million in capital funding to ensure the facility remains world-class and continues to meet the needs of researchers and industry,” Dr Paterson said. 

“This is a great first step, and we look forward to continuing to work with industry and government to support the vitally important work of our scientists and researchers.” 

Australian Synchrotron Director, Professor Andrew Peele said the expansion will alleviate demand issues and enable new research opportunities. 

“This expansion will give Australian and New Zealand industry and our best and brightest scientific minds access to even more specialised tools and techniques needed for important research,” said Professor Peele.

“This will enable them to continue to compete on the world-stage and deliver real-life benefits to the community.” 

ANSTO will continue to work with universities and other stakeholders to secure the remainder of the required funding. 

Contributors to the project include:

Australian National University - Charles Sturt University - Curtin University – Deakin University - Macquarie University – Monash University - Queensland University of Technology - RMIT University - Swinburne University - University of Canberra - University of Melbourne - University of New South Wales - University of Queensland - University of the Sunshine Coast - University of Sydney - University of Tasmania - University of Western Australia - University of Wollongong – Walter and Eliza Hall Institute of Medical Research – ANSTO - Defence Science and Technology Group - New Zealand Synchrotron Group (including contributions from the New Zealand government and 10 universities and research institutions) 

Media enquiries: 

Minister Sinodinos: Nat Openshaw 0409 049 128

ANSTO / Australian Synchrotron: Phil McCall 0438 619 987

 

Queensland researchers have shown that single crystals, typically thought of as brittle and inelastic, are flexible enough to be bent repeatedly and even tied in a knot.

Researchers from Queensland University of Technology and The University of Queensland (UQ) determined and measured the structural mechanism behind the elasticity of the crystals down to the atomic level using the Australian Synchrotron.

Video: Copyright QUT

Their work, published in Nature Chemistry, opens the door for the use of flexible crystals in applications in industry and technology. 

The research was led by ARC Future Fellows Associate Professor Jack Clegg in UQ’s School of Chemistry and Molecular Biosciences and Associate Professor John McMurtrie in QUT’s Science and Engineering Faculty. 

Associate Professor McMurtrie said the results challenged conventional thinking about crystalline structures.

“Crystals are something we work with a lot – they’re typically grown in small blocks, are hard and brittle, and when struck or bent they crack or shatter,” he said.

“While it has previously been observed that some crystals could bend, this is the first study to examine the process in detail.

“We found that the crystals exhibit traditional characteristics of not only hard matter, but soft matter like nylon.”

The researchers grew bendable crystals about the width of a fishing line and up to five centimetres long from a common metal compound – copper (II) acetylacetonate.

They mapped changes in the atomic scale structure when the crystals were bent using X-ray measurements performed at the Australian Synchrotron.

A view of the structural deformation on the elongated (left) and compressed (right) areas of the crystal.

Dr Jason Price, a beamline scientist at the Australian Synchrotron, who helped design the experiments, explained that preliminary studies were undertaken on the MX1 beamline and followed by extensive measurements on the MX2 beamline.

“This experiment really shows the opportunity to look at variation within a single crystal. The microfocus capacity of the beam at MX2 is such that it can gather data from different parts of the crystal, so, when it is under strain from expansion or compression.”

 Crystals from six other structurally related compounds, some containing copper and some other metals, were also tested and found to be flexible.  

Associate Professor Clegg said the experiments showed that the crystals can be repeatedly bent and return quickly to their original shape with no signs of breaking or cracking when the force bending them is removed.

“Under strain the crystal molecules reversibly rotate and reorganise to allow the compression and expansion required for elasticity and still maintain the integrity of the crystal structure,” he said.

“The ability of crystals to bend flexibly had wide-ranging implications in industry and technology.

“Crystallinity is a property that underpins a variety of existing technologies, including semi-conductors and lasers which are used in almost every electronic device from DVD players to mobile phones and computers.

“But the hardness that makes them suitable for high-strength industrial components limits their use in other technologies. Flexible crystals like these could lead to new hybrid materials for numerous applications from components of planes and spacecraft to parts of motion or pressure sensors and electronic devices.”

Associate Professor McMurtrie said the method the researchers have developed to measure the changes during bending could also be used to explore flexibility in any other crystals.

“This is an exciting prospect given that there are millions of different types of crystals already known and many more yet to be discovered,” he said.

“Bending the crystal changes its optical and magnetic properties, and our next step is to explore these optical and magnetic responses with a view to identifying applications in new technologies.”

The research was funded by an ARC Discovery Grant and supported by the Australian Synchrotron. Research collaborators and co-authors of the study are: Anna Worthy, Professor Chen Yan, and Yanan Xu (QUT) and Dr Arnaud Grosjean, Dr Michael Pfrunder and Dr Grant Edwards (UQ).

http://dx.doi.org/10.1038/nchem.2848  

For interview:

QUT Associate Professor John McMurtrie, j.mcmurtrie@qut.edu.au   07 3138 1220

UQ Associate Professor Jack Clegg, j.clegg@uq.edu.au  0408 642082