Big Data and Materials Design: Towards a Blueprint for Improving Batteries and
Catalysts
Sarbajit BanerjeeDepartment of Chemistry
Department of Materials Science and [email protected]
Cottrell Scholar
DMR CAREERPFI:AIR
Oxides for Electronics and Conventional/Renewable Energy Applications
Phase Transitions in Nanostructures: Electron Correlated Materials with Massive Electronic or Magnetic Transitions
Nanoscale Imaging of Geometric and Electronic Structure Using Synchrotron Methods
Solution‐Grown Nanocrystals: Mechanistic Understanding of how Molecular Precursors Influence Crystal Growh
Nanocomposite Coatings Incorporating Carbon and Light Metal Nanostructures for Corrosion Protection
So how does one design a material to fulfill a certain function?
Only about 5% of the 160,000 possible ternary materials are known 99% of the 4 million possible quaternaries remain unexplored
Atomistic Structure – Mesoscale Architecture – Bulk Properties
“Computers in the future may weigh less than 1.5 tons”Popular Mechanics, 1949
Some Lessons from Technology…
IEEE Spectrum
Not just beating on silicon but expanding the palette…
Lessons from Technology: A Study in Contrasts
Jean-Marie Tarascon
Needle in a Haystack…• Could you computationally screen
compounds and make only those that are interesting?
-Materials Genome Initiative Hattrick-Simpers, Catal. Lett. 2015, 145, 290-298
Predicting Crystal Structure
Identifying Metastable Phases
Precisely Predicting Electronic Structure (properties that turn on a dime)
Electron Correlation
Kinetics across Interfaces
…Another way to approach this problem is to find a system where a number of different parameters are independently variable: Libraries of compounds
Bringing data science to bear on a couple of specific problems…
(i) Batteries
(ii) Photocatalysts
Learning from spectroscopy data-how can we do better?
- Accelerating materials design-making informed decisions, identifying targets, and rapid optimization
“After many years of almost suspended animation, the battery-electric vehicle industry is showing signs of life. At the Exide motor, Mr. D. P. Dunne stated that the monthly output of these vehicles in Great Britain is larger than it has ever been before. Compared with petrol vehicles, they make less noise and produce less atmospheric pollution.”
Nature 134, 657 27 October 1934
Cathode Design: The Weakest Link?
Cathode Design: Some things to consider…
Electronic Structure
Mesoscale Structure
Atomistic Structure
Life Beyond Li Ion…
V2O5 as a Cathode Material
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Layered 2D framework with plenty of room to accommodate cations and even solvated cations
J. M. Velazquez and S. Banerjee, Small, 2009, 5, 1025-1029.
Accommodating Lithium…
Probing Structure Using X-ray
Spectroscopy
Incident Photon Energy
2s 1s
2pEAuger
h90°
Eh0°
E
J. M. Velazquez, C. Jaye, D. A. Fischer, and S. Banerjee, J. Phys. Chem. C. 2009, 113, 7639-7645.
Split-off conduction band Due to interaction between V 3dxy –Oc
2px/2pyAttributed to V3d and O2p orbitals that have
the smallest π type overlap→ the smallest bonding antibonding splitting
Learning from Synchrotron Spectroscopy
5460 5465 5470 5475 5480 5485 5490 5495 5500 5505
0.0
0.5
1.0
N
orm
aliz
ed
(E) (
a.u.
)
Incident Photon Energy (eV)
Increasing Li
Applying Multivariate Curve Resolution
Lee, J. L. S., & Gilmore, I. S. (2009). The Application of Multivariate Data Analysis Techniques in Surface Analysis. Surface Analysis - The Principal Techniques.
Multivariate Curve Resolution: When Li Enters Slowly
Metastable phaseLi Li Li
Multivariate Curve Resolution: When Li Enters Fast
Li Li
PCA Mapping of Li-Gradients and Phase Separation
Least lithiated (0 < x < 0.3)
Most lithiated (0.9 < x <1.2)
Medium lithiated (0.3 < x < 0.9)
STXM maps inhomogeneous lithiationInsertion of Li-ions is anisotropic and between layersMultiphase domains within nanowires-depending on size…
PCA Image
Eigen Spectra
What Slows Down Li-Ion Diffusion?
Increase in charge density Decrease in charge density
Added electron localizes on a single vanadium atom within dxy orbitals
Stabilization of a Polaron
Charge transport based on variable range hopping till sufficient Li-ion concentration is reached
Vanadium Oxide Bronzes for Electrochemical Energy Storage
Open frameworks‐plenty of space to accommodate cations
Multivalent redox material: V5+ to V4+ to V3+
Electrically conductive
• Domains form because of polaronic confinement at low Li concentrations-ionized Li occupies dxy level of individual V atoms instead of delocalizing
• Small polarons remain confined until enough Li-ions are inserted wherein polarons can coalesce
How can one design a new phase to limit such polaronic confinement?
ζ-V2O5: A New Tunnel Structured Phase of V2O5
P. M. Marley, T. A. Abtew, K. E. Farley, G. A. Horrocks, R. V. Dennis, P. Zhang, and S. Banerjee,* Chemical Science 2015, 6, 1712-1718.
Isolated at nanoscale dimensions by leaching of Ag-ions from AgxV2O5
Stable up to 650C
Can be packed with Li+, Ga+, Mg2+
First new V2O5 phase in >100 years
Packing the Empty Tunnels with Mg and Li: Reconfiguring MxV2O5
Re-insertion of Li, Ga, and Mg ions illustrates access to a whole new class of structures
Pathways for Li and Mg Diffusion in New Phase
Desired characteristics:
(i) “One size too big” but metastable(ii) Polaronic delocalization
Hundreds of Potential New Phases
(i) Most of these phases are “metastable”-not easily accessed by theory
(ii) How to rapidly screen candidates for desirable characteristics without having to make and characterize every phase?
(iii) How to mine heterogeneous data for correlations? How to incorporate support vector machines in decision making?
Solar Energy Conversion: The Defining Challenge of our Times?
Use sunlight to produce O2 and H2 from H2O
Energy is stored in the H2 bond
Sun, J.; Zhong, D. K.; Gamelin, D. R. Energy & Environmental Science 2010, 3, 1252.Lewis, N. S.; Nocera, D. G. Proceedings of the National Academy of Sciences of the United States of America 2006, 103, 15729-35.
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2H2O → O2 + 4H+ + 4e-
E°R(O2/H2O) = +1.23 V vs. NHE4H+ + 4e- → 2H2
E°R(H+/H2) = 0 V vs. NHE
Getting Thermodynamics and Kinetics Right
Mid-Gap States
Marley, P. M.; Stabile, A. A.; Kwan, C. P.; Singh, S.; Zhang, P.; Sambandamurthy, G.; Banerjee, S. Adv. Funct. Mater. 2013, 23, 153.Wangoh, L.; Marley, P. M.; Quackenbush, N. F.; Sallis, S.; Fischer, D. A.; Woicik, J. C.; Banerjee, S.; Piper, L. F. J. Appl. Phys. Lett. 2014, 104, 182108.
Valence Band
Conduction Band
Mid-gap State
Ef
Pb 6s—O 2p interaction gives rise to a mid‐gap state in the band gap
A Tunable Platform for Precisely Engineering Photocatalysts
β‐MxV2O5 Nanowires/II‐VI Quantum Dots
Intrinsic mid‐gap states of NWs are more positive than oxidation potential of water while more negative than QD valence bands
Mid‐gap states can be tuned by changing stoichiometry/cation identity
Quantum dot valence bands can be tuned by varying composition of quantum dot
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-PbxV2O5Na2Se
EtOH
Cd(NO3)2
EtOH nCdSe-PbxV2O5
Electronic Structure of Heterostructures
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Spectral data shows presence of mid-gap state
Overlap of CdSe valence band and β-PbxV2O5 mid-gap state
β-PbxV2O5β-PbxV2O5β-PbxV2O5β-PbxV2O5
Pelcher, K. E.; Milleville, C. C.; Wangoh, L.; Chauhan, S.; Crawley, M. R.; Marley, P. M.; Piper, L. F. J.; Watson, D. F.; Banerjee, S. Chem. Mater. 2015, 27, 2468.
Condensing Learning Cycles• How to identify targets based on
heterogeneous mixtures of experimental and theoretical data?
• How to identify associations, correlations, and clustering from spectroscopic data?
• How to develop parametric models that do not require full-scale first-principles calculations?