Constructing Well-Defined and Robust Th-MOF-Supported Single-Site Copper for Production and Storage of Ammonia from Electroreduction of Nitrate

Abstract

A combined technique of production and storage of ammonia (NH 3 ) from electroreduction of nitrate (NO 3 – ) through one material is highly desirable but remains a huge challenge. Herein, we proposed a proof-of-concept strategy for combined NH 3 production and storage from electroreduction of NO 3 – through elaborately designing a single-site Cu II -bipyridine-based thorium metal–organic framework (Cu@Th-BPYDC). Noticeably, the single Cu II site, anchored by a solid–liquid postsynthetic metalation within Th-BPYDC, shows a novel square coordination structure, as determined by the single-crystal X-ray diffraction. This strongly implies its enormous potential as an open metal site and consequently enables excellent performance in electroreduction of NO 3 – for NH 3 production, giving 92.5% Faradaic efficiency and 225.3 μmol h –1 cm –2 yield. Impressively, we can further use Cu@Th-BPYDC material to effectively capture the previously produced NH 3 from electroreduction of NO 3 – , affording an uptake up to 20.55 mmol g –1 at 298 K at 1 bar. The results in this work will outline a new direction toward the combined technique for advanced electrocatalysis such as gas production plus storage/or separation.

Subnanometric alkaline-earth oxide clusters for sustainable nitrate to ammonia photosynthesis

“…Another virtue of using NO 3 − feedstock lies in its rich distribution in wastewater. The abundant nitrate in wastewater offers sufficient reactants for NO 3 − reduction reaction (NO 3 − RR) routes 17 – 20 . Instead of the partial reduction of NO 3 − to N 2 for its purification, the eight-electron transfer reaction for NO 3 − to NH 4 + synthesis provides an opportunity for the value-added conversion of contaminative NO 3 − into ammonia as an economically competitive product.…”

Electropolymerization of Metal Clusters Establishing a Versatile Platform for Enhanced Catalysis Performance

“…À to valuable NH 3 . [11] Especially, copper catalysts and their derivatives have been explored for the NRA reaction with high efficiency. [11a,f,i,j] Based on the above considerations, we investigated the electrocatalytic NRA activity of Poly-Cu 14 cba.…”

“…Recently, electrochemical reduction of nitrate (NO 3 − ) to ammonia (NRA) has been demonstrated as an attractive alternative approach, since this reaction converts the widespread water pollutant NO 3 − to valuable NH 3 [11] . Especially, copper catalysts and their derivatives have been explored for the NRA reaction with high efficiency [11a,f,i,j] . Based on the above considerations, we investigated the electrocatalytic NRA activity of Poly‐Cu 14 cba .…”

Electropolymerization of Metal Clusters Establishing a Versatile Platform for Enhanced Catalysis Performance

“…As shown in Figure 3c, the NH 3 yield rate gradually increases with a more negative potential from −0.75 to −1.15 V vs. RHE, while the Faradaic efficiency of NH 3 is represented by a volcanic shape curve, and the maximum value is calculated to be 90 % at −1.05 V vs. RHE. Further increasing of the potential results in a decrease of Faradaic efficiency, which is probably due to increased competitive hydrogen evolution reaction (HER) [11a,j] . The maximum selectivity value of NH 3 was 80 % at −1.05 V (Figure S13).…”