Figure 4: Dependence of A. ferrooxidans growth on light wavelength and intensity.
From: Growth of non-phototrophic microorganisms using solar energy through mineral photocatalysis
(a) Growth curves of A. ferrooxidans under different conditions. This graph shows the dependence of cell growth on wavelength of visible light. A light intensity of 8 mW cm−2 (of the rutile surface area) was used. (b) The dependence of current density on wavelength. The highest current density at 420 nm corresponds to the highest cell growth yield. (c) The photoelectric efficiency of the rutile-A. ferrooxidans system, as a function of light wavelength (orange curve), showing that the efficiency is the highest at 420 nm, which accounts for the highest cell growth yield. These measurements were made at a fixed light intensity 8 mW cm−2 over the logarithmic phase of the cells. The light absorption spectrum of rutile is also plotted as a function of light wavelength (green curve). (d) The dependence of the cell concentration of A. ferrooxidans (at day 4) on light intensity at a fixed wavelength of 420 nm (red curve). Current density is also plotted as a function of light intensity (green curve).
