Manipulating dehydrogenation kinetics through dual-doping Co<sub>3</sub>N electrode enables highly efficient hydrazine oxidation assisting self-powered H<sub>2</sub> production.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32296070.
- Also identified by DOI 10.1038/s41467-020-15563-8 and PMC identifier 7160107.
- 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
Replacing sluggish oxygen evolution reaction (OER) with hydrazine oxidation reaction (HzOR) to produce hydrogen has been considered as a more energy-efficient strategy than water splitting. However, the relatively high cell voltage in two-electrode system and the required external electric power hinder its scalable applications, especially in mobile devices. Herein, we report a bifunctional P, W co-doped Co<sub>3</sub>N nanowire array electrode with remarkable catalytic activity towards both HzOR (-55 mV at 10 mA cm<sup>-2</sup>) and hydrogen evolution reaction (HER, -41 mV at 10 mA cm<sup>-2</sup>). Inspiringly, a record low cell voltage of 28 mV is required to achieve 10 mA cm<sup>-2</sup> in two-electrode system. DFT calculations decipher that the doping optimized H* adsorption/desorption and dehydrogenation kinetics could be the underlying mechanism. Importantly, a self-powered H<sub>2</sub> production system by integrating a direct hydrazine fuel cell with a hydrazine splitting electrolyzer can achieve a decent rate of 1.25 mmol h<sup>-1</sup> at room temperature.