There is an urgent need for sustainable sources of both energy and clean water. Herein, a novel highly efficient, cost-effective, scalable, adaptable and successive water-energy synergistic system (WESS) is developed using in-series flexible and permeable photocatalytic cell (PC) units for electricity production coupled with water treatment. Each PC unit is assembled as a monolithic device by integrating a Ti-mesh-based, high length-diameter ratio, single crystalline, 3–D anatase TiO2 nanowire array as a photoanode, a low-cost nylon net as a separator, and a carbon felt with improved surface graphitization and graphitic N as an efficient oxygen reduction reaction cathode. The WESS shows excellent energy recover and organic removal for different electrolyte concentrations, treatment capacities, substrate concentrations, and pollutant types. Notably, non-linear and marvellous improvements are achieved in both power output and organic degradation as the unit number increased. We attribute this behaviour to synergistic effects between the PC units, originating from the interactional potential in the serial system which accelerated the charge transfer of photoanode and electrode/electrolyte interface. In this case, a nine-unit WESS successively removed &gt;99.8% of methyl orange accompanying with a maximum power density (Pmax) of ~10.53 mW cm–2, which was ~120 times as great as the highest Pmax of a photo-fuel-cell reported to date. This system also exhibited outstanding stability in long-term implementations. Moreover, efficient electricity generation and organic removal were achieved for the WESS under real sunlight and with an input of salty/seawater. The present novel strategy will pave the way for further systematic design of water-energy nexus techniques in clean energy production and wastewater resource utilization fields.

Highly adaptable, successive water-energy synergistic system for efficient electricity production coupled with water treatment

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.