(Invited) Plasmonic Aerogels for Gas-Phase Photocatalytic Reactions

Abstract

As a special form of material, aerogel has emerged as a promising type of photocatalyst. Owing to the large specific surface area and the developed pore texture, it would be suitable to drive various gas-phase reactions such as CO2 reduction and CH4 conversion. More importantly, the size of the fundamental building blocks in an aerogel, which is typically 5-20 nm, is approaching that of the noble metals with the surface plasmon resonance (SPR) effect. Innovated by Rolison and Niederberger(1, 2), aerogels with plasmonic effect have been extensively studied as photocatalysts for hydrogen evolution and dye degradation in liquid mediumThis talk then aims to introduce some of our recent results on the construction and evaluation of plasmonic noble metal/ceria composite aerogels, which cover the content from the synthesis to new applications. Modified synthesis methods are developed for the rational incorporation of plasmonic metal nanoparticles such as Ag and Au into an aerogel backbone in one step, which offers an alternative route to tune the composition and size of these nanoparticles, or even building single-atom composite aerogels in the conventional sol-gel methodology(3). When these plasmonic aerogel photocatalysts are applied for gas-phase CO2 reduction and non-oxidative CH4 coupling reaction, good performance is observed. The synergistic effect of plasmonic sensitizer and co-catalyst is discussed and is responsible for the performance enhancement. P. A. DeSario, J. J. Pietron, A. Dunkelberger, T. H. Brintlinger, O. Baturina, R. M. Stroud, J. C. Owrutsky and D. R. Rolison, Langmuir, 33, 9444 (2017). F. Rechberger and M. Niederberger, Nanoscale Horizons, 2, 6 (2017). M. Wu, C. Ouyang, Z. Ye, S. Li, Z. Hong and M. Zhi, ACS Applied Energy Materials, 5, 7335 (2022).