Photocatalytic hydrogen production is one of the most important techniques, which have to be part of a sustainable energy system to ensure the survival of our polluted planet. The search for the most efficient photocatalyst for this technique includes not only finding the right material, but as importantly, finding the right structure. We suggest 3D, translucent, nanoparticle-based aerogel monoliths as promising candidates for the photocatalytic hydrogen production in the gas phase. To achieve the best photocatalytic performance, the right fit between the geometries of especially 3D photocatalysts and reactors measuring their performance is crucial. Here, we report how we take control of the geometry of the photocatalyst by introducing 3D printed polymeric scaffolds into the aerogels. Thanks to these scaffolds, we can investigate the gas flow through the aerogel, the UV light penetration into the aerogel and the optimal fit with our custom-made continuous gas flow reactor to maximize the hydrogen production rate. We manage to raise the hydrogen production rate from originally 433 µmol g-1 h-1 by a factor of almost 4 to 1578 µmol g-1 h-1 just by modifying the geometry of the aerogels. Additionally, the rigid scaffolds enhance the mechanical stability of the fragile aerogels, increasing the fabrication yield and, therefore, saving material, money and time. With the possibility to engineer these 3D printed polymeric scaffolds, we can match the geometry of any 3D, template-free, self-supporting photocatalyst to the geometry of reactors built for any photocatalytic gas phase reaction and maximize the photocatalytic performance.

How 3D printed polymeric scaffolds optimize geometry, mechanical stability and photocatalytic performance of nanoparticle-based aerogels

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.