Affiliation:
1. Laboratory of Spine and Spinal Cord Injury Repair and Regeneration Ministry of Education Tongji Hospital School of Chemical Science and Engineering Tongji University Shanghai 200092 China
Abstract
AbstractThe electrochemical denitrification of nitrate (NO3−) in actual wastewater to nitrogen (N2) is an effective approach to reversing the current imbalance of the nitrogen cycle and the eutrophication of water. However, electrostatic repulsion between NO3− and the cathode results in the low efficiency of NO3− reduction reaction (NO3RR). Here, density functional theory (DFT) calculations are used as a theoretical guide to design a Pd cluster‐loaded multivalent Cu foam (Pd/Cu2O‐CF) electrocatalyst, which achieves a splendid 97.8% NO3− removal rate, 97.9% N2 selectivity, 695.5 mg N g−1Pd h−1 reduction efficiency, and 60.0% Faradaic efficiency at −1.3 V versus SCE. The projected density of states (pDOS) indicates that NO3− and Pd/Cu2O‐CF are bonded via strong complexation between the O 2p (in NO3−) and Cu 3d (in Cu2O) with the input of voltage, which reduces the electrostatic repulsion and enhances the enrichment of NO3− on the cathode. In‐situ characterizations demonstrate that Pd[H] can reduce Cu2O to Cu, and subsequently Cu reduces NO3− to nitrite (NO2−) accompanied by in situ reconfiguration of multivalent Cu foam. NO2− is then transferred to the surface of Pd clusters by the cascade catalysis and accelerates the breaking of N─O bonds to form Pd─N, and eventually achieves the N≡N bond formation.
Funder
National Natural Science Foundation of China
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry