Increasing efficiency of photovoltaics via surface plasmon polariton scattering effects in metallic nanostructures
University of California, San Diego, US
surface plasmon, plasmon, photovoltaic, solar, energy, nanotechnology
Metallic nanostructures can exhibit pronounced absorption and scattering effects at optical frequencies due to the existence of collective electron excitations known as surface plasmon polaritons. These effects have been exploited in a variety of applications ranging from molecular spectroscopy to biological tagging to production of colored glass artifacts. We have recently demonstrated that scattering from metal nanoparticles placed in proximity to a solid-state semiconductor photodiode can be engineered to yield increased optical absorption and photocurrent generation over a broad range of visible wavelengths, and have applied this concept to thin-film amorphous silicon photovoltaic devices to achieve substantial increases in energy conversion efficiency. Specifically, low densities of metal nanoparticles integrated with an amorphous silicon photovoltaic device have yielded increases in short-circuit current and energy conversion efficiency of 1.08-1.13x, and numerical simulations indicate that, at higher particle densities, increases of 1.4x should be attainable. These results and a variety of related approaches to improving efficiency of photovoltaics will be discussed.
Back to Program