| Affiliation: | 1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500 China
School of New Energy and Materials, Southwest Petroleum University, Chengdu, 610500 China;2. School of New Energy and Materials, Southwest Petroleum University, Chengdu, 610500 China;3. XJTU-Oxford International Joint Research Laboratory of Catalysis, School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an, 7010049 China;4. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500 China |
| Abstract: | Electrochemical nitrate (NO3?) reduction to ammonia (NH3) offers a promising pathway to recover NO3? pollutants from industrial wastewater that can balance the nitrogen cycle and sustainable green NH3 production. However, the efficiency of electrocatalytic NO3? reduction to NH3 synthesis remains low for most of electrocatalysts due to complex reaction processes and severe hydrogen precipitation reaction. Herein, high performance of nitrate reduction reaction (NO3?RR) is demonstrated on self-supported Pd nanorod arrays in porous nickel framework foam (Pd/NF). It provides a lot of active sites for H* adsorption and NO3? activation leading to a remarkable NH3 yield rate of 1.52 mmol cm?2 h?1 and a Faradaic efficiency of 78% at ?1.4 V versus RHE. Notably, it maintains a high NH3 yield rate over 50 cycles in 25 h showing good stability. Remarkably, large-area Pd/NF electrode (25 cm2) shows a NH3 yield of 174.25 mg h?1, be promising candidate for large-area device for industrial application. In situ FTIR spectroscopy and density functional theory calculations analysis confirm that the enrichment effect of Pd nanorods encourages the adsorption of H species for ammonia synthesis following a hydrogenation mechanism. This work brings a useful strategy for designing NO3?RR catalysts of nanorod arrays with customizable compositions. |
