Self-sustained photocatalytic power generation using eco-electrogenic engineered systems.

An eco-electrogenic engineered system (EES) was designed to mimic the functional role of natural aquatic ecosystems and evaluated their response to bio-electrogenic activity by cascadically interlinking three tanks with functionally diverse biota viz., floating macrophytes (Tank 1), submerged plants (Tank 2) and filter feeders (fish and snails) (Tank 3). Tank 1 showed efficient power generation (voltage (series): 0.86 V; current density (parallel): 37 mA/m) than Tank 2 (voltage (series): 0.76 V; current density (parallel): 34 mA/m) and Tank 3 (voltage (series): 0.65 V; current density (parallel): 22 mA/m). Integrating all three tanks enabled maximum power generation in parallel-series (P-S) connection (9.5 mW/m) than individual series and parallel connections (6.5/5 mW/m). Interaction of microbes and plants studied at the interface of electrochemical and engineering aspects illustrated the feasibility of EES as a self-sustainable system with innate diverse functional aquatic biota and rhizo-microbiome to produce bioelectricity.