High-efficiency nitrate electroreduction to ammonia on electrodeposited cobalt-phosphorus alloy film

Electrocatalytic eight-electron nitrate (NO3-) reduction is a sustainable strategy to degrade NO3- and convert it into high value-added ammonia (NH3) but needs efficient catalysts with high activity and selectivity. Our study shows the use of Ti plate supported cobalt-phosphorus alloy film (Co-P/TP) as a highly active and selective electrocatalyst for ambient NO3--to-NH3 conversion. In 0.2 M Na2SO4 with 200 ppm NO3-, Co-P/TP offers an NH3 yield rate of 416.0 +/- 7.2 mu g h(-1) cm(-2) and a high faradaic efficiency of 93.6 +/- 3.3% at -0.6 V and -0.3 V vs. reversible hydrogen electrode, respectively, with good durability. Noticeably, a conversion rate of 86.9% is achieved after 10 h bulk electrolysis.

Automated summary

The study demonstrated the use of a Ti plate supported cobalt-phosphorus alloy film as a highly active and selective electrocatalyst for the conversion of nitrate to ammonia. The catalyst showed high NH3 yield rate, Faradaic efficiency, and durability under experimental conditions.