Pixel International Conferences

The production of hydrogen with sunlight is becoming increasingly important and offers various possibilities. One approach in current research is to embed a light-driven catalytic molecule within a hierarchically structured soft matrix to use solar radiation within a chemical reaction for photocatalytic water splitting [1].
This article presents the further development of an experiment on photocatalytic water splitting [2] with the aim to improve the conversion rate and ultimately the hydrogen evolution. The photosystem consists of titanium dioxide (catalyst), Eosin Y (photosensitive molecule), triethanolamine (electron donor) and is enhanced by the addition of simple polymers (e.g., polyacrylic acid) that form a suitable matrix and aid the reaction.
Based on the didactic reductions already made, the quantitative determination of hydrogen by the low-cost hydrogen sensor of the LabPi system [3] is to be extended by the qualitative observation of a gas evolution with the naked eye. For this purpose, further parameters that influence the conversion rate will be optimised. On the one hand, through the addition of ethanol, which acts as a catalyst in the right concentration range. On the other hand, the addition of suitable co-catalysts has shown to significantly improve the conversion rate [4]. Furthermore, the concentrations of the reactants are investigated. By using a simple daylight source, the reaction can be carried out independent of external influences (season, clouds, sunlight intensity, etc.) at the optimum efficiency in a short time.
The experiment offers a first insight into the development of a future generation of materials, which represent an approach for sustainable hydrogen development through sunlight. The subject area also offers numerous links to classical school contents (i.e., catalysis, energy conversion, redox reactions, polymers) as well as to basic concepts of chemistry (energy, structure-property). Lastly, the link between photochemistry with an Education for Sustainable Development can be taken up synergistically [5].