Fig. 1. Optical images of the chl-a fluorescence of H. coffeaeformis (diatom, CCAP 1001/2) during the fluoro-electrochemical experiment, where tpot. on is the time which a potential step of 2.3 V (vs. pseudo Ag wire) was applied to the working electrode. λex = 475 ± 35 nm and λem > 590 nm. The blue line depicts the location of the carbon fibre electrode. A potential of 0 V (vs. pseudo Ag wire) was applied for t = 0–60 s, before the potential steps to 2.3 V for t = 60–90 s.
