Abstract

2. Plasmonics for Sustainability: harvesting light energy for new solar applications The intense research activity of the past two decades focused on the collective electronic oscillations in high-electron-density media, known as surface plasmons, has led to multiple breakthroughs in fields ranging from chemical sensing and catalysis, to active optical devices, solar light harvesting, even nanomedicine. For many of these applications, the original focus on noble metals may ultimately limit their transition from the research laboratory to widely used commercial technologies. We will describe several research directions that, as they point towards more sustainable materials, open up new research opportunities. Aluminum, the most abundant metal on earth, opens the door to new colorimetric sensing applications and opportunities for active devices[1-4]. Graphene in its smallest form, that of polycyclic aromatic hydrocarbon molecules, can support intense, optical frequency plasmon oscillations with the addition or removal of a single electron from the neutral molecule. In applications that directly address sustainability, we will discuss how plasmonic nanoparticles can be used to generate steam using nanoparticles and sunlight without heating the fluid volume. This effect can be used for a wide range of direct solar processes and applications, such as the solar distillation of liquids and of liquid mixtures [5-9], the green production of bioethanol from cellulosic feedstock, and a direct solar-driven approach to membrane distillation suitable for off-grid, remote site applications.

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