New paper published in Applied Catalysis B: Environmental which explores a promising new approach to resource recovery and wastewater treatment. Nitrate is widely distributed in industrial wastewater and contaminated water bodies, and electrochemically converting it into ammonia holds great potential. At the same time, the treatment of harmful algal blooms (HABs) presents a significant challenge worldwide. It’s time-consuming, resource-intensive, and has a high CO2 footprint. But what if we could see this carbon and nitrogen-rich biomass as a vast renewable resource, rather than disposable waste? That’s precisely what we set out to do.
Within our Sino-German collaboration, we developed a Fe-dispersed carbon-based catalyst derived from HABs biomass. The resulting material achieved a maximum ammonia yield rate of 16449 μg/h/cm2 (1.2 mmol/h/mg_cat) and NH3 Faradaic efficiency of 87.3%. Furthermore, the catalyst demonstrated excellent stability, with continuous operation over 50 hours. Our experimental and theoretical calculation results suggest that the Fe-N4 site facilitates the electrocatalytic nitrate reduction reaction by reducing the energy barriers of the NO3–-to-NH3 pathway.
We believe our strategy of upcycling HABs biomass waste into functional catalysts represents a significant step forward in renewable and carbon-neutral energy technologies. We are grateful for the opportunity to contribute to this field and are excited to continue exploring new solutions to some of our most pressing environmental challenges.