Direct Nitrogen Fixation in Air Over Soil Using Dielectric Barrier Discharge Plasma for Enhanced Plant Growth

ABSTRACT Artificial nitrogen fixation through high‐voltage discharging using renewable energy sources could be a controllable and sustainable path to feed the increasing global population. In this research, soil, as a carrier and catalyst, was filled between the electrodes of a dielectric barrier discharge (DBD) plasma to accelerate nitrate nitrogen (NO 3 – ‐N) production from the ambient air at atmospheric pressure. DBD plasma could increase the NO 3 – ‐N content in soil up to 80 mg kg ‐1 in either yellow or red soils within 20 s. The minerals of transition metals in soil were important for the synthesis of NO 3 – ‐N. Precipitated NO 3 – ‐N in the red or yellow soil promoted water spinach's biomass and N uptake.