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Nanomaterials for Energy

Nanomaterials for Energy

Center for NanoscienceUniversity of Missouri-St Louis, St. Louis, MO63121

Center for NanoscienceUniversity of Missouri-St Louis, St. Louis, MO63121

Missouri Energy Summit, Columbia, MO, 23 April 2009

Missouri Energy Summit, Columbia, MO, 23 April 2009

Jingyue (Jimmy) Liu and Eric Majzoub

Jingyue (Jimmy) Liu and Eric Majzoub

Patrick KinlenCrosslink, St. Louis, MO 63026

Patrick KinlenCrosslink, St. Louis, MO 63026

Outline Outline 1) Introduction to energy usage

2) The role of nanocatalysts

3) Nanomaterials for hydrogen storage

4) Nanostructured polymer solar cells

5) Supecapacitors and batteries

6) Summary

1) Introduction to energy usage

2) The role of nanocatalysts

3) Nanomaterials for hydrogen storage

4) Nanostructured polymer solar cells

5) Supecapacitors and batteries

6) Summary

Clothing

Shelter

Water

The Necessities of Human Survival

Food

What More Do We Want?

Improving Quality of Life

Transportation

Health Health

Communication

Environment Environment

FoodWaterShelterClothing

Health

Environment

Tra

nsp

ort

ati

on

Com

mu

nic

ati

on

Energy

En

erg

y

Energy

En

erg

yNatural Gas

Nuclear

Coal

Petroleum

BiomassBiomass

HydroHydro

Geothermal

Geothermal

Wind

Wind

Solar

Solar

EIA

US Energy Consumption by Source(1980-2030)

QBtu

EIA

We will still depend on dwindling fossil fuels unless major events

occur

The role of nanocatalysis in energy

Energy efficiency for existing chemical processes

Coal to liquid (CTL) fuel and gas to liquid (GTL) fuel processes for mid-term

Hydrogen production

Low temperature hydrogen or alcohol fuel cells

CTL technology could be a competitive and an assured source of transportation fuels. Coal gasification offers less costly capture and compression of CO2, and with sequestration Fischer-Tropsch fuels can have a lower carbon footprint than traditional petroleum-based fuels.

Coal-to-liquids (CTL) technology by Fischer-Tropsch processes

(2n+1)H2 + nCO → CnH(2n+2) + nH2O

CnH(2n+2) + ½ nO2 → (n+1)H2 + nCO

CHx + H2O → (1+0.5x)H2 + CO

F-T process

Syngas process

Catalysts consist of Co, Ni, Ru or combinations

Hildebrandt et al., Science 323 (2009) 1680

3C + 4H2O    2CO + 4H2 + CO2    2(-CH2-) + 2H2O + CO   

3C + 6H2O    3CO2 + 6H2    2(-CH2-) + 4H2O + CO2      

New reaction processes can reduce energy and CO2

emissions

Storage typeEnergy density by

mass (MJ/Kg)Energy density by

volume (MJ/L)

Hydrogen (700bar) 143 5.6

Hydrogen liquid 143 10.1

Hydrogen gas 143 0.01079

Methane (1.03bar 55.6 0.0378

Natural gas 53.6 10

LPG propane 49.6 25.3

LPG butane 49.1 27.7

Gasoline 46.4 34.2

Biodiesel 42.2 33

Butanol 36.6 29.2

Ethanol 30 24

Methanol 19.7 15.6

Glucose 15.55 23.9

Zinc 5.3 38

Energy density of various energy carriers

Stored H2

PEMFuel cell

H2O

H2

Electricity

CAT

H2 Production from H2O

CAT

Technical challenge:High efficiency, long life time, low cost and safety

Technical challenge:High efficiency, long life time, low cost and safety

Hydrogen Energy CarrierHydrogen Energy Carrier

H2

Metal HydridesCNT

Metal-organic Frameworks

PEM Fuel Cell for Automobiles

Stored H2

PEMFuel cell

H2O

H2

Electricity

CAT

Reformer

Fuel tank

CO2

H2 CH3OHCH3CHOH

CAT

H2Production

CAT

High effi ciency, long life time, low cost and safetyHigh effi ciency, long life time, low cost and safety

PEM Fuel Cell for Automobiles

Stored H2

PEMFuel cell

H2O

H2

Electricity

CAT

Reformer

Fuel tank

CO2

H2 CH3OHCH3CHOH

CAT

Reformer

Fuel tank

CO2

H2 CH3OHCH3CHOH

CAT

H2Production

CAT

High effi ciency, long life time, low cost and safetyHigh effi ciency, long life time, low cost and safety

CH3OH + H2O CO2 + 3H2

CH3OH -- CO + 2H2

CO + H2O -- CO2 + H2

Cu/ZnO/Al2O3

Hydrogen Production by Steam Reforming of

Methanol

Catalyst issue: Deactivation caused by Cu

sintering Safety issue

Hydrogen Production by Steam Reforming of

MethanolCatalyst issue:

Pd/ZnO generates high amount of CO

Iwasa’s group obtained better CO selectivity and catalyst stability by reducing Pd/ZnO at moderate to high temperaturesExplanation: formation of PdZn alloy

nanoparticles (similar band structure to Cu)

Detailed nanostructural mechanisms are lacking

Our recent research is to develop practical nanostructured model catalyst to understand the synthesis-structure-performance relationships of the Pd/ZnO nanocatalyst

Preparation and characterization of Pd/ZnO precursor materials

In situ heat treatment at various temperatures and characterization

In situ catalytic reactions and characterization

1 m

ZnO Nanoblets/Nanoribbons

2 nm2 nm

In situ Heat Treatment400°C55 minLayers of Pd and Zn atomsFormation of PdZn L10 alloy

[100] zone axis

ZnPd

PEM Fuel Cell

H+

Anode CathodeCatalyst

H2Air +H2O

Anode:H2(g) 2H+(aq) + 2e-Cat

Catalysts: Pt, PtRu, PtMo, …Major issues: CO, CO2

Cathode:O2(g) + 4H+(aq) +4e- 2H2O(l)

Cat

Catalysts: Pt, PtNi, PtCr, PtCo, …Major issues: activity, stability

Influence of the surface morphology and electronic surface properties on the kinetics of ORR. RRDE measurements for ORR in HClO4 (0.1 M) at 333 K with 1600 revolutions per

minute on Pt3Ni(hkl) surfaces as compared to the corresponding Pt(hkl) surfaces

Marković/Ross 2007

1 nm

4-nm Pt-Ni alloy nanoparticle showing the preferentially exposed (111) surfaces, which provide much better catalytic performance in hydrogen based fuel cells.

2 nm

Design and Fabricate Desired Nanoparticle Fuel

Cell Catalysts

Hydrogen StorageAnother key challenge to the hydrogen economy

Majzoub Research GroupMajzoub Research GroupTheory and ExperimentFor Energy Utilization

Theory and ExperimentFor Energy Utilization

KineticsKinetics

H2 storage targetsH2 storage targets

ThermodynamicsAnd Phase Stability

ThermodynamicsAnd Phase Stability

Modern Hydrogen Storage Materials

NaAlH4 band structureNaAlH4 band structureComplex Ionic Hydrides•Wide gap insulators

(vs. metal interstitial)•Large wt.% of hydrogen•LiBH4 18%•LaNi5H6 1.2%

Complex Ionic Hydrides•Wide gap insulators

(vs. metal interstitial)•Large wt.% of hydrogen•LiBH4 18%•LaNi5H6 1.2%

• Desirable hydrogen enthalpy: 20-40 kJ/mol H2

• Nanoscale materials for thermodynamic tuning• Control particle size and S/V ratio

• MgH2: ΔH = 75kJ/mol H2

• Develop new materials with size control of nanoparticle metals!

• Desirable hydrogen enthalpy: 20-40 kJ/mol H2

• Nanoscale materials for thermodynamic tuning• Control particle size and S/V ratio

• MgH2: ΔH = 75kJ/mol H2

• Develop new materials with size control of nanoparticle metals! (de Jong, JACS, 127, 16675, 2005)

The Sun Provides Us Energy

Harvest 1 hour of sunlight is enough for 1 year’s energy use for

the whole world

Solar Panels: Directly Convert Sun

Energy to Electricity or Heat

What is the problem?

Advanced Technology of New Nanostructured Polymer Solar

Cells

Advanced Technology of New Nanostructured Polymer Solar

Cells

Flexible, high efficiency and low cost

3rd G 4th G

Printable & Flexible Plastic Solar Cells

Photoactive polymer blend P3HT:PCBM

Conducting polymer

Al

e +

P3HB: poly(3-hexylthiophene)

PCBM: [6,6]-phenyl-C61 butyric acid methyl ester

Electron donor and transporter of holes

Electron acceptor and transporter

100 nm

Printable Electronics

Super Capacitors and Batteries

New nanostructures can make significant

improvement

Coin Cell Supercapacitor: Coin Cell Supercapacitor: Role of PANI Conductivity on Device Role of PANI Conductivity on Device

PerformancePerformance

Enhancement in conductivity of PANI Enhancement in conductivity of PANI Film contributes to Boost Coin Cell Film contributes to Boost Coin Cell

Energy and Power Densities Energy and Power Densities

Coin Cell Supercapacitor: Coin Cell Supercapacitor: Role of PANI Conductivity on Device Role of PANI Conductivity on Device

PerformancePerformance

Polyaniline (PANI)

Film

Electrical Conductiv

ity (S/cm)2

Specific Capacitance (F/g)3

Energy Density (WH/Kg)

4

PAC 1003 film

0.2 1.2 0.38

Novel Secondary Doped

PAC 1003 Film

250 6.13 1.92

1000 12.48 3.39

4000 17.21 5.38

SummarySummary Nanostructured materials play a

major role in solving the energy challenges in the 21st century

The Center for Nanoscience at UM-St. Louis, working together with local research institutions and companies, is poised to develop alternative energy sources

Nanostructured materials play a major role in solving the energy challenges in the 21st century

The Center for Nanoscience at UM-St. Louis, working together with local research institutions and companies, is poised to develop alternative energy sources

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