Cutting Biofuel Production Costs
Working to use sunlight to convert biomass to biofuels, researchers have found a pathway toward reducing the energy costs associated with making renewable biofuels. To achieve this, they designed semiconducting nanorods that act as light harvesting antennas, and attached metal nanoparticles that are activated by energy from the sun. This nanostructured photocatalyst converted bioderived alcohols to benzaldehyde, toluene, and the zero-emission biofuel hydrogen. Benzaldehyde is used as an almond-flavoring agent in foods and as a precursor for many pharmaceuticals, and toluene is a common industrial solvent. The metal nanoparticles, made from platinum or palladium, not only provided photocatalytic activity, but also prevented etching and degradation of the nanorods. By tuning the composition of the nanorods and the amount of metal attached (less being better!) the production of hydrogen could be increased relative to that of benzaldehyde and toluene. Further tuning and new designs of these photocatalytic nanocomposites are expected to lead to additional ways to produce lower-cost biofuels from sunlight.