Big Data and Materials Design: Towards a Blueprint for Improving Batteries and

Catalysts

Sarbajit BanerjeeDepartment of Chemistry

Department of Materials Science and Engineeringbanerjee@chem.tamu.edu

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?