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Mullins Research Group – Materials Chemistry for Energy

Materials Chemistry for Energy

3. Electrode Materials for Li-Ion Batteries

1. Nano-Structured Materials for SolarPhotoelectrocatalysisfor Fuels

Surface Chemistry,Catalysis, Electrocatal.,

Of Nano-Structured Surfaces

Prof. Allen Bard

Prof. Henkelman

Prof. Adam Heller

Prof. Hwang

Iron Oxide NanoColumns

Gold Clusters on Titania

2.

& &

Prof. Crooks

Solar Photoelectrochemical Water-Splitting to Produce Hydrogen

hh+

n-typesemiconductor

photoanode

e-

cat.H2O

O2 + 4H+

CATHODE

cat.

4H+

2H2 New materials and device architecturescould make these processes more efficient and less costly!

Solar Photoelectrochemical Water-Splitting

h

PhotocatalyticMaterial

Section of Single FeatheryNanocolumn

OH- ½O2Solution“Feathery Filament”From Nanocolumn

H+

H2 h

PhotocatalyticMaterial

Section of Single FeatheryNanocolumn

OH- ½O2Solution“Feathery Filament”From Nanocolumn

H+

H2

1. Pick “Candidate”Abundant, Metal-Oxide Photoelectrocatalysts

2. Rapid SynthesisAnd Screening

3. Deposit PromisingMetal-Oxide

Materials with Nano-Structured

Morphology

4. CharacterizeMaterial

5. TestPhotoelectrochemically

TiO2 Nano-Structured Films

H3C-CH2OH

OH3C-CH2O—H--

H3C-CHOH2O

Au/Pd Alloy Surface

Surface Chemistry/Catalysis/Electrocatal.of Nano-Structured Surfaces

Surface Chemistry/Catalysis/Electrocatal.of Nano-Structured Surfaces

Clusters on Supporting Surface

Exploratory studies ofcatalysis/“surface chemistry”- green processing, fuel cells

and fundamental insights.

Nano-Structured Titanium Carbide Film which has Pt-like Catalytic Properties.

Examples

TiO2 Clusters on Au(111) SurfaceOsgood, Hrbek-Nano Lett. (2005)

Gold Clusters on TitaniaGoodman-Science (1998)

Na,Li-Ion Battery OperationDischarging

Anode ActiveMaterial

CuAl Li+

Li+

Li+

Cathode ActiveMaterial

Electrolyte

e-

e- e- e- e-

e-

e-e-

ConductiveAdditive

Polymer Binder

Na,Li-Ion Battery OperationRecharging

CuAl Li+

Li+

Li+

Electrolyte

e-

e- e- e- e-

e-

e-e-

Anode ActiveMaterial

Cathode ActiveMaterial

ConductiveAdditive

Polymer Binder

Electrode Materials for Na,Li-Ion Batteries

Iron Oxide Nanorods GrownHydrothermally

Silicon Nanoparticles in Carboxymethyl-Cellulose Binder with Carbon Nanotubes

and Carbon Nanoparticles

Graphite is typically used as anode in Li-Ion batt.’s but safety issues persist

Need alternate materials and architectures:

•Low voltage vs. Li/Li+•High capacity•High Li transport•Good electron conductor•Large volume change•Low cost and abundant •Non-toxic/environmentally

benign

Our approach involves nanostructured sample synthesis, materials characterization, and electrochem.testing (e.g., Li transport rate, cyclability, capacity, etc.)

200 nm

Germanium Nanorods Grownby Glancing Angle Deposition

A day in the labs ….Device Testing

Catalysis & Surface Chemistry

Complex Materials Synthesis

Sample Exchange

Substrate Holder

Evaporators

16o

WBi V

Mo

FTO Substrates