Abstract
Surface plasmons have shown increasingly widespread applications in the last decade, especially in the field of solar energy conversion, recently leading to the use of metal nanoparticles as plasmonic photocatalysts. The latter offers great potential in overcoming traditional catalysts by providing localized heating and unconventional reaction pathways leading to improved product selectivity. A complete understanding of the underlying mechanisms remains, however, elusive due to the close resemblance between thermal and non-thermal effects, both leading to enhanced reaction rates. In this tutorial, we will introduce the basic physics of surface plasmons and the interaction mechanisms with surrounding molecules. We will then discuss the main strategies to evaluate photothermal effects and the main signatures of hot electron-driven processes. These aspects will be covered in specific examples of plasmonic photocatalysis for energy-relevant chemical reactions in the case of colloidal suspensions and at the solid/gas interphase in solid pellets, which involve different thermal constraints and thus different experimental strategies to reveal the effects of localized heating and hot electrons.
Highlights
At the beginning of the 20th century, the rise in the world population was depleting the deposits of KNO3 that constituted the natural supplies of nitrogen-based fertilizers, endangering the planet of starvation
We will discuss the main strategies to evaluate photothermal effects and the main signatures of hot electron-driven processes. These aspects will be covered in specific examples of plasmonic photocatalysis for energy-relevant chemical reactions in the case of colloidal suspensions and at the solid/gas interphase in solid pellets, which involve different thermal constraints and different experimental strategies to reveal the effects of localized heating and hot electrons
After the initial wave of reports showing the potential advantages of the new class of plasmonic photocatalysts, especially the possibility of tuning the product selectivity, the scientific community has recently realized the subtle difficulty in properly accounting for non-thermal effects and their distinction from thermal ones
Summary
At the beginning of the 20th century, the rise in the world population was depleting the deposits of KNO3 that constituted the natural supplies of nitrogen-based fertilizers, endangering the planet of starvation. Only carrier-mediated and local field-enhanced processes offer the possibility of tuning the reaction pathways.[8,9,10] As a consequence, recent investigations are making an effort to shed more light on the fundamental principles underlying these catalytic processes, with the aim of enabling the realization of efficient and scalable plasmonic photocatalysts This tutorial aims first at giving a basic introduction about the field of plasmonic photocatalysis, explaining the differences and similarities with “traditional” catalysis and photocatalysis; second, at describing the basic physical–chemical mechanisms involved in plasmonic nanoparticles in contact with molecules; and third, at discussing examples of plasmonic photocatalysis in colloidal systems and at the solid/gas interphase in solid pellet catalysts through the identification of thermal and non-thermal mechanisms in these two cases. The readers interested in further knowledge in the field and in other aspects that have not been included here are referred to systematic reviews.[8,9,10,12,13,14]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call