Photosynthetic biofilms have much higher cell density than suspended cultures and when grown in a stacked waveguide configuration, can have orders of magnitude higher areal productivity. Evanescent and plasmonic growth of biofilm cultures have been demonstrated, solving issues with light penetration impeding growth, but thus far the technology has been limited to biofuel production applications. In this thesis, plasmonically excited cyanobacterial biofilms are used to produce electrical power in a photosynthetic-plasmonic-voltaic device. This approach uses red lasers to deliver light to cells via an optical waveguide through the generation of surface plasmons at the interface between a metal and dielectric, in this case a glass-gold-air interface. This gold film serves a dual purpose as a current collector for electrons generated at the cell surface. Experiments presented here demonstrate positive power output light response under both direct light and plasmonic excitation and produced equivalent power output of 6 uW/m2 under similar light power intensities.

Photosynthetic biofilms have much higher cell density than suspended cultures and when grown in a stacked waveguide configuration, can have orders of magnitude higher areal productivity. Evanescent and plasmonic growth of biofilm cultures have been demonstrated, solving issues with light penetration impeding growth, but thus far the technology has been limited to biofuel production applications. In this thesis, plasmonically excited cyanobacterial biofilms are used to produce electrical power in a photosynthetic-plasmonic-voltaic device. This approach uses red lasers to deliver light to cells via an optical waveguide through the generation of surface plasmons at the interface between a metal and dielectric, in this case a glass-gold-air interface. This gold film serves a dual purpose as a current collector for electrons generated at the cell surface. Experiments presented here demonstrate positive power output light response under both direct light and plasmonic excitation and produced equivalent power output of 6 uW/m2 under similar light power intensities.