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Tailoring Nanostructured Catalysts in a Hydrogen Economy. Prof. Paolo FORNASIERO Department of Chemistry University of Trieste, Italy pfornasiero@units.it. Le filiere dell’energia- Trieste, 26.11.2010. H 2 PRODUCTION TECHNOLOGIES. Eolic. Electrolysis. Hydro- electric. Reforming. Solar.
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TailoringNanostructuredCatalystsinaHydrogenEconomy Prof. Paolo FORNASIERO Department of Chemistry University of Trieste, Italy pfornasiero@units.it Le filiere dell’energia- Trieste, 26.11.2010
H2 PRODUCTION TECHNOLOGIES Eolic Electrolysis Hydro- electric Reforming Solar size of production cost of available feedstocks Geothermal Fermentation + Reforming Biomass Gasification Pyrolysis + Reforming Gas Oil Carbon
H2 H2O O2 Proton Exchange Membrane Fuel Cells (PEM-FC) H2 PRODUCTION & PURIFICATION • Active and stable catalysts are required for large scale applications • Most efficient catalyst (electrodes) for H2 utilization in Fuel Cells
EMBEDDING APPROACH encapsulationofpreformed metal nanoparticles intoMOxthroughdifferentmethodologies
Protected Impregnated Rh@Al2O3 for MPO 1% Rhimpregnated vs 1% Rhembedded @Al2O3 T = 750°C T. Montini, A. M. Condó, N. Hickey, F. Lovey, L. De Rogatis, P. Fornasiero and M. Graziani, Applied Catalysis B: Environmental73 (2007) 84-97
Ru@LSZ for NH3 DECOMPOSITION Reaction with pure NH3 GHSV T = 500°C 4000 mL g-1 h-1 T = 700°C 30000 mL g-1 h-1 B. Lorenzut, T. Montini, C. C. Pavel, M. Comotti, F. Vizza, C. Bianchini and P. Fornasiero, ChemCatChem2 (2010), 1096-1106 .
Cu@TiO2 for PHOTOCATALYTIC H2 PRODUCTION hn > 3.0 eV Water splitting: Very low efficiency Organic molecule as sacrificial agents Renewable compounds
vs Cu@TiO2 Cu/TiO2 Cu@TiO2 for PHOTOCATALYTIC H2 PRODUCTION • Experimental condition: • Medium pressure Hg lamp 125W • 0.500 g catalyst • 240 mL of solution • Argon flow 15 mL/min Ar in Ar in Ar out Ethanol/water 1:1 Glycerol 1M H2 Evolution rate (mmol/h) Evolution rate (mmol/h) CO2 Time (h) Time (h) V. Gombac, L. Sordelli, T. Montini, J. J. Delgado, A. Adamski, G. Adami, M. Cargnello, S. Bernal and P. Fornasiero, Journal of Physical Chemistry A 114 (2010), 3916-3925
FE-SEM 550°C 550°C 1 μm 200 nm plane-view cross-section O2 + H2O atmosphere granular Cu2O films… plane-view cross-section dry O2 atmosphere …CuO 1D nanoarchitectures
50 40 CuO 30 H2 production/L h-1 m-2 20 10 Cu2O 0 0 2 4 6 time/h 5 4 CuO 3 H2 production/L h-1 m-2 2 1 Cu2O 0 0 2 4 6 time/h Photocatalyticsplittingof H2O/CH3OH (1:1) solutions H2 production Fornasiero P. et al., ChemSusChem2009, 2, 230 Effect of catalyst recycling UV-Vis (125 W) 30000 Activity normalized for the catalyst amount 25000 20000 H2 production/L h-1 m-2 g-1 15000 10000 CuO 5000 0 0 5 10 15 20 25 time / h Vis (125 W) Radiation switched off for 12 h • Significantly better performances than commercial CuxO (<580 L h-1 m-2 g-1) • high timestability of the catalyst
CORE-SHELL STRUCTURE DESIGN COOH-Ce bond stable Ce-OR bond not stable Pd-S bond stable
Pd@CeO2 DISPERSIBLE STRUCTURES AS BUILDING BLOCKS Al2O3 Pd(1%)@CeO2(9%)/Al2O3 Methanol Steam Reforming WGSR CO oxidation JACS2010, 132, 1402-1409
ADVANCED ELECTRODES for SOFCs Cathode: Perovskite ABO3 La1-xSrxNi0.6Fe0.4O3-d ZrO2-based solid electrolite 8-YSZ Anode: LSCM + CeO2 + Pd LSCM =La0.8Sr0.2Cr0.5Mn0.5O3 Catalytic component CeO2-Pd
50 μm 100 μm 50 μm ADVANCED ELECTRODES for SOFCs: ANODE
ADVANCED ELECTRODES for SOFCs: ANODE - 15 % Pd@CeO2 - 15% Maximum power density (W/cm2) - 26 % Pd/CeO2-1 - 26% Pd/CeO2-2 - 42 % - 43% Time (h)