Hybrid Inorganic-Organic Materials for Energy: Silica & Films for Fuel Cells, Study notes of Spanish Language

Download Hybrid Inorganic-Organic Materials for Energy: Silica & Films for Fuel Cells and more Study notes Spanish Language in PDF only on Docsity! 6-50 nm cubic hexagonalhexagonal cubic lamellar spheresspheres For example, EO EOPO m mn CH3CH3 CH3CH3 CCH2 H2 Mesostructured silica 10 nm 50 nm New Hybrid Inorganic-Organic Materials for Energy Applications D. Zhao et al., Science, 279, 548, 1998 Cubic Hexagonal cubic cubicbicontinuous bicontinuous with Prof. Galen Stucky, UCSB Prof. Glenn Fredrickson, UCSB One Example: Proton-Exchange Membranes in Fuel Cells PEM Fuel Cell Ion-conducting channel > 80 oC< 80 oC Anode Cathode Membrane H2 H2 Air Air, water NafionTM 800 m2/g 12 nm SO3H O Re O O O Si H3C Al Functionalization of Inorganic-Organic Solids catalysis: biodiesel opto-electronics, optical materials fuel cell membranes electrodes capacitors F F Focused ion-beam TEM: Mesoporous Carbon film cross-section Mesoporous Carbon Films Electrodes Capacitors Electrocatalysts Mesoporous Carbon Films Surface Area: 400 m2/g Conductivity: 10 S/cm Carbon Cloth Electrodes Surface Area: 50 m2 Conductivity: 40 – 50 S/cm By comparison, G.L. Athens, B.F. Chmelka, Adv. Mater., submitted. Dehydration of Polymeric PEM Materials e.g., Nafion® DuPont Ion-conducting channel Yeager, Steck, J. Electrochem. Soc., 185, 1880, 2001 > 80 oC < 80 oC 800 m2/g Filling of Remaining Mesopore Volume with Triflic Acid (CF3SO3H) SO3H F2 F3C F SO 3H F 2F 3C F SO3H F2 F3C F SO3H F2 F3C F SO3H F2 CF3F SO3H F2 CF3F SO3H F2 CF3F SO3H F2 CF3F SO 3 HF 2 CF 3 F SO 3 HF 2 CF 3 F SO3H F2 CF3F SO3H F2 CF3F SO3H F2 CF3F SO3H F2 CF3F SO3H F2 CF3F SO 3 H F 2 CF 3 F F HO3S F2CF3 F SO 3 HF 2 CF 3 F HO3S F2CF3 F F3CSO3- H+ F 3 CSO 3 -H + F 3 CS O 3 - H + F 3 CSO 3 -H + F3CS O3 - H+ F3C SO3 - H+ F 3 C SO 3- H + F3CSO3- H+ F 3 C SO 3 -H + F3CSO3- H+ F 3 CS O 3 - H + F3CSO3- H+ F3CS O3 - H+ F3CS O3 - H+ F 3C SO 3 - H+ F 3CSO 3 -H+ F 3 C SO 3 - H + 50 nm • Increases concentration of acid moieties • Improves barrier properties Surface-grafted PFSA Pore-filling triflic acid Approach Hierarchical design of inorganic materials 50 nm 29Si 1H • Molecular functionalization of block-copolymer- templated mesoporous silicas • Incorporation of aluminosilica moieties to control adsorption properties • Incorporation of acidic moieties to introduce ion-conduction properties • Characterization of material properties over molecular, meso-, macroscopic length scales • Feedback to synthesis, processing, modelling