A group of researchers from the University of Auckland, the University of Aberdeen, and the Universitat Politècnica de Catalunya have utilized sunlight and ethanol to produce hydrogen.
A powder photocatalyst, developed for the research, simplified the hydrogen production process because it helps the process take place at ambient pressure and temperature.
The photocatalyst was placed in a container having ethanol and was exposed to UV light by agitation. The unit features a titanium dioxide semiconductor, which generate electrons when it comes in contact with the sunlight. The electrons are captured by gold nanoparticles that react with alcohol molecules to generate hydrogen. Researcher at the Universitat Politècnica de Catalunya's Nanoengineering Research Centre, Jordi Llorca stated that the contact with the nanoparticles and the structure of the semiconductor are critical features in the photocatalyst’s design.
The quantity of energy and hydrogen generated depends on the region exposed to solar radiation and the quantity of catalyst used. The researchers used ethanol instead of water because it delivered poor results and the materials required for the manufacturing process was pricey. Moreover, ethanol can be obtained from forest and agricultural waste.
The photocatalyst utilizes small-sized gold particles that range in sizes between 2 and 12 nm. The gold nanoparticles capture the electrons produced when titanium oxide, which is used as a support base, comes in contact with sunlight. The researchers also found that hydrogen generation is not influenced by the size of the gold nanoparticles.