Environmental and Energy. Catalysis by Nanostructures. Nanostructured
catalysts already widely used for: Pollutant clean-up: e.g., catalytic converter in
autos - ...
Environmental and Energy Catalysis by Nanostructures Nanostructured catalysts already widely used for: Pollutant clean-up: e.g., catalytic converter in autos - probably prevented more cancer death that all medical treatment combined Chemicals production with less energy consumption, less polluting side products. Fuel conversions to more efficient, cleanly-burning forms.
Promising future: Nanostructures now can be made with tuned reactivity, and far more homogenous in structure- key to high selectivity! So… soon we could have (with proper research) lots better catalysts, thus: cleaner cars, chemical industry, power plants, heating. But…nanostructures are inherently unstable wrt larger structures, leads to catalyst deactivation, slower catalyst development.
Electronic character of nanoparticles are tunable, with size as “knob”. Different colors for different sizes of nanoparticles of same semiconductor (Bawendi, Brus, Alivisatos, Nie, others).
Bright idea: catalytic properties also ought to be tunable for metal nanoparticles.
Implications of Particle Size wrt: Chemisorption and Catalytic Reactivity •
Atoms of same element which are more “coordinatively unsaturated” (i.e., have fewer neighbors) tend to bind next species more strongly. Example: Bond energy between 2 C atoms increase as the number of H or R neighbors decreases: H3C …… CH3 90 kcal/mol H2C …… CH2 146 kcal/mol HC …… CH 200 kcal/mol.
