**Table 5.**

*Microbial photobioelectrochemical cells with chemotrophic bioanode and photocathode that generate electricity.*

The device was able to reduce 97% of an initial concentration of 25 mg/L of Cr(VI) while it was illuminated; moreover, it could still maintain the reduction reaction, albeit slower, while the light was absent [42].

Two devices used polydopamine coated titanium dioxide nanotubes as photocathode material. Both were used to catalyze MoS2 nanoparticle synthesis. In this case, the focus of the devices was to be used as catalyzers to produce the semiconductor nanoparticles, instead of oxidizing organic matter or generate added value such as electricity or hydrogen. It was demonstrated that MoS2 obtained through these systems can be used for hydrogen generation under visible light illumination [39, 54].
