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Transcript of Nanomaterials for Energy Center for Nanoscience University of Missouri-St Louis, St. Louis, MO63121...
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