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.

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A research-style laboratory experiment composed of the synthesis of MOF-74 materials, related structural characterization, and the cutting-edge application of electrocatalytic oxygen evolution reaction (OER) has been designed toward advanced undergraduates at East China University of Technology (ECUT). The desired monometallic MOF-74 (Ni-MOF-74 and Co-MOF-74) and bimetallic NiCo-MOF-74 were synthesized by students using cheap raw materials under mild reaction conditions. Students operated the modern instruments to perform powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA) applied extensively in chemical research to explore whether the materials were successfully synthesized and the thermal stability under the guidance of the instructor. The electrocatalytic OER activity of bimetallic NiCo-MOF-74 was compared with monometallic Ni-MOF-74 and Co-MOF-74 to explore and understand the bimetallic synergy effect in MOFs materials. This experiment not only enabled students to master the solvothermal method for MOFs synthesis but also provided students the chance to operate several common chemical instruments and master their functions, realizing the application of theoretical knowledge to practice. Most importantly, this experiment helped students realize the importance of MOFs in the electrochemical energy fields and established a sense of teamwork by analyzing and discussing the bimetallic synergy effect in NiCo-MOF-74 for OER catalysis.

Metal‐organic frameworks (MOFs) have exhibited huge potential in electrocatalytic fields. However, the intrinsic low conductivity and the blockage of metal active sites by organic linkers still seriously hinder their large‐scale application. In this study, as a proof of principle, constructing cofacial π–π stacking in the terminal ligand (4,4′‐bipyridine) of a Ni/Fe‐chain‐based MOF to fabricate strong π–π interaction, in combination with unique hexagonal nanorod (HXR) structure, is found to be an effective strategy to enhance one‐dimensional charge carrier efficiency and thus achieve excellent activity in the oxygen evolution reaction (OER). The approach yields a high turnover frequency (4.54 s−1) in well‐designed bimetallic chain‐based MOFs (NiFe‐HXR) at an overpotential of 350 mV, which is about 8.7 and 34.9 times higher than those in Ni‐HXR (0.52 s−1) and IrO2 (0.13 s−1), respectively. This work effectively combines “through‐bond” channel in chain‐based structure of NiFe‐HXR and “through‐space” transport between face‐to‐face terminal ligands, thus resulting in outstanding OER activity. This strategy of modulating the structure chemistry and morphology of MOFs to promote the OER may open a new perspective to synthesize MOFs for energy‐relevant electrochemical reactions.