Fe 3 O 4 nanoparticle-decorated 3D pinewood-derived carbon for high-efficiency electrochemical nitrate reduction to ammonia.

Electrochemical nitrate (NO 3 - ) reduction is a sustainable pathway for ambient ammonia (NH 3 ) synthesis while eliminating NO 3 - pollutants in water. However, the NO 3 - reduction reaction (NO 3 - RR) involves a complicated eight-electron transfer process, which needs highly selective and efficient electrocatalysts. This work describes the synthesis of Fe 3 O 4 nanoparticle-decorated 3D pinewood-derived carbon (Fe 3 O 4 /PC) as a high-efficiency catalyst for the electroreduction of NO 3 - to NH 3 at ambient reaction conditions. When tested in 0.1 M NaOH containing 0.1 M NO 3 - , the Fe 3 O 4 /PC obtains a large NH 3 yield of 394.8 μmol h -1 cm -2 and high faradaic efficiency (FE) of 91.6% at -0.4 V. Significantly, Fe 3 O 4 /PC also delivers high stability.