High‐Efficiency Electrocatalytic Conversion of Nitrite to Ammonia Using Nickel Phthalocyanine

Abstract Nitrite (NO 2 − ) is a dangerous pollutant that is often found in groundwater sources and endangers human health. In addition to nitrite removal requirements, electrocatalytic nitrite reduction reaction (eNO 2 RR) holds promise for value‐added ammonia (NH 3 ) production at room temperature. In this study, a solvothermal technique for the preparation of nickel phthalocyanine (NiPc) is used as a highly active electrocatalyst for the conversion of NO 2 − to NH 3 under ambient conditions. The NiPc catalyst shows a remarkable Faradaic efficiency (FE) of 90.1% at −0.9 V versus RHE with maximum ammonia yield rate of 14667 µg h −1 mg cat. −1 at −1.0 V versus RHE in 0.1 M Na 2 SO 4 containing 0.1 M NaNO 2 solution. Furthermore, the catalyst exhibits exceptional long‐term stability during chronoamperometry tests. These findings boost the future ammonia production from nitrite reduction for sustainable development.