Electricity-powered artificial root nodule.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32198474.
- Also identified by DOI 10.1038/s41467-020-15314-9 and PMC identifier 7083970.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Root nodules are agricultural-important symbiotic plant-microbe composites in which microorganisms receive energy from plants and reduce dinitrogen (N<sub>2</sub>) into fertilizers. Mimicking root nodules using artificial devices can enable renewable energy-driven fertilizer production. This task is challenging due to the necessity of a microscopic dioxygen (O<sub>2</sub>) concentration gradient, which reconciles anaerobic N<sub>2</sub> fixation with O<sub>2</sub>-rich atmosphere. Here we report our designed electricity-powered biological|inorganic hybrid system that possesses the function of root nodules. We construct silicon-based microwire array electrodes and replicate the O<sub>2</sub> gradient of root nodules in the array. The wire array compatibly accommodates N<sub>2</sub>-fixing symbiotic bacteria, which receive energy and reducing equivalents from inorganic catalysts on microwires, and fix N<sub>2</sub> in the air into biomass and free ammonia. A N<sub>2</sub> reduction rate up to 6.5 mg N<sub>2</sub> per gram dry biomass per hour is observed in the device, about two orders of magnitude higher than the natural counterparts.
Medical subject headings
- Electricity
- Electrochemistry
- Root Nodules, Plant