Rational Design of Energy Materials

The project uses atomic-scale simulations to accelerate the design of novel materials for low-carbon energy generation, transformation and transport. In particular we focus on understanding the degradation mechanisms that affect current materials used in (a) batteries, (b) solar cells and (c) nuclear reactors, and we use this understanding to design materials resilient to degradation. The materials we develop enable a more sustainable, less resource-intensive, form of clear energy generation.
Person

Principal investigator

Patrick A Burr p.burr@unsw.edu.au
Magnifying glass

Area of science

Earth Sciences, Geosciences, Materials
CPU

Systems used

Magnus
Computer

Applications used

VASP, LAMMPS, Iradina
Partner Institution: UNSW| Project Code: pawsey0289

The Challenge

From a technological point of view, the transition to a clean energy future is largely limited by the performance of current materials used for energy applications. These materials are exposed to harsh environment that are far from equilibrium. Exemplar cases are (a) battery materials, continually cycled from one metastable state to the other in a corrosive environment, and (b) solar cells, exposed to solar irradiation and weather events.
To achieve a sustainable and low CO2 energy future, new materials must be developed that are not only more efficient, but crucially they must be more resilient to degradation in these harsh conditions, so that they can be utilised for longer, thereby reducing the burden on earth’s resource utilisation.

The Solution

We accelerate the development of new improved energy materials by combining stat-of-the-art simulations with advanced experimental techniques. In our project, the experiments, which are inherently timely and costly, are guided by a mechanistic insight of the degradation processes that we develop through our atomic-scale simulations. Our approach starts by developing a mechanistic understanding of the degradation process – for example why do electrodes formed of amorphous TiO2 nanotubes perform better in Li-ion batteries that bulk crystalline counterparts? Once the mechanism is understood, we exploit it to our advantage by identifying alternative materials that should exhibit the same mechanism to greater effect. The list of potential candidates is typically very large, so again we use atomic-scale simulations to down-select only those that are predicted to be readily synthesisable. Finally, we set out to fabricate the materials in the lab, using the atomic-scale insight to optimise the fabrication conditions.

The Outcome

Our approach has been successful in two key areas: solar cells, battery electrodes
(1) For solar cells, our simulations linked the fabrication conditions (temperature and oxygen partial pressure) to the structure and performance of the MoO3 “contact layer”, which is an important component of advanced solar cell design with higher efficiency. This enables the fabrication of advanced silicon solar cells with MoO3contact layers, and reduced degradation with time due to cross-contamination of Mo in silicon.
(2) Fast charging of batteries is essential for their integration in power grids, but for current state-of-the-art technology this causes accelerated degradation. We have identified that amorphous metal oxide electrodes can sustain faster charging and discharging rates than crystalline electrode, with significantly less degradation. This is due to the mechanism through which Li ions diffuse in amorphous materials. In addition, we have identified strategies to reduce the fragmentation of amorphous Si electrodes during charge-discharge of battery, by simple doping and pre-lithiation steps. This finding may enable Si-based electrodes for high-power batteries, which would greatly reduce the cost and processing compared to the current state-of-the-art.

List of Publications

C.O.T Galvin, P.A. Burr, M.W.D Cooper, P.C.M. Fossati, R.W. Grimes
“Using molecular dynamics to predict the solidus and liquidus of mixed oxides (Th,U)O2 , (Th,Pu)O2 and (Pu,U)O2”
J. Nucl. Mater. (2020)

D.S. Lambert, A. Lennon, P.A. Burr
“Diffusion mechanisms of Mo contamination in Si”
Phys Rev Mater 4 (2020) 025403

D. Lau, C.A. Hall, S. Lim, J.A. Yuwono, P.A. Burr, N. Song, A. Lennon
“Reduced Silicon Fragmentation in Lithium Ion Battery Anodes Using Electronic Doping Strategies”
ACS Appl. Energy Mater. 3 (2020) 1730-1741

S.X. Oliver, M.L. Jackson, P.A. Burr
“Radiation-induced evolution of tungsten carbide in fusion reactors: accommodation of defect clusters and transmutation elements”
ACS App. Energy Mater 3 (2020) 868-878

D.G. Frost, C.O.T. Galvin, M.W.D. Cooper, E.G. Obbard, P.A. Burr
“Thermophysical properties of urania-zirconia (U,Zr)O2 mixed oxides by molecular dynamics”
J. Nucl. Mater. 528 (2019) 151876

T.M. Whiting, P.A. Burr, D.J.M King and M.R. Wenman
“Understanding the importance of the energetics of Mn, Ni, Cu, Si and vacancy triplet clusters in bcc Fe”
J. Appl. Phys. 126 (2019) 115901

C.A. Hall, A. Ignjatovic, Y. Jiang, P.A. Burr and A. Lennon
“Time domain modelling of concurrent insertion and capacitive storage using Laplace domain representations of impedance”
J. Electroanal. Chem. 850 (2019) 113379

B. Zheng, J.E. Fletcher, A. Lennon, Y. Jiang and P.A. Burr
“Improving Generation Ramp Rates of Photovoltaic Systems using Module-Based Capacitive Energy Storage”
J. Power Sources (2019) 423, 227-235

A. Lennon, Y. Jiang, C. Hall, D. Lau, N. Song, P.A. Burr, C.P. Grey, and K.J. Griffith
“High-rate lithium ion energy storage to facilitate increased penetration of photovoltaic systems in electricity grids”
Energy & Sustainability 6 (2019), E2

A Jain, P.A. Burr and D. Trinkle
“First-principles calculations of solute transport in zirconium: Vacancy-mediated diffusion with metastable states and interstitial diffusion”
Phys. Rev. Matter. 3 (2019) 033402

P.A. Burr and S.X. Oliver
“Formation and migration of point defects in tungsten carbide: unveiling the sluggish bulk self-diffusivity of WC”
J. Europ. Ceram. Soc. 39 (2019) 165-172

P.A. Burr, E. Kardoulaki, R. Holmes, S.C. Middleburgh
”Defect evolution in burnable absorber candidate material: Uranium diboride, UB2”
J. Nucl. Mater. 513 (2019) 45–55