In‐situ Electrochemical Activation Enhances the OER Catalytic Performance of Ag NWs@ZIF‐67 in Alkaline Simulated Seawater

• Published in: ChemistrySelect (Weinheim) Vol. 7; no. 22
• Main Authors: Wang, Mengzhen, Lian, Xiao, Wu, Mingzai, Zheng, Fangcai, Niu, Helin
• Format: Journal Article
• Language: English
• Published: 13.06.2022
• Subjects: electrostatic adsorption; In-situ electrochemical activation; nanocatalysts; Zeolitic imidazolate framework
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202201305

Modification of MOFs by in‐situ electrochemical activation is a simple and convenient way. Two dimenstional Zeolitic Imidazolate Framework‐67 (the following is abbreviated as 2D‐ZIF 67) nanosheets were grown on the surface of silver nanowires using a bottom‐up concentration‐controlled method. Due to the inductive effect of the solvent, the nanosheets grow in the direction favorable for the OER catalytic reaction, so the material exhibits an overpotential of 250 mV in both alkaline aqueous solution and alkaline simulated seawater at a current density of 10 mA.cm−2, not subject to CER competition. After in‐situ electrochemical activation in alkaline simulated seawater, oxygen vacancies and reactive sites were generated on the surface of the composites by the synergistic effect of current and electrolyte. Under the same effect, AgCl@Co(OH)2 heterogeneous interface were formed between the Ag nanowires and 2D‐ZIF67 nanosheets. As a result, the OER catalytic performance was further improved, and the overpotential was only 222 mV in alkaline simulated seawater. In this research, we combined the superior electrical conductivity Ag NWs with ZIF‐67, which has poor electrical conductivity. The composites have excellent OER catalytic performance in alkaline aqueous solution and alkaline simulated seawater. At the same time, the catalytic performance of the material was further improved under the action of in‐situ electrochemical activation, which greatly promoted the direct application of MOFs in seawater electrolysis.