Yasir Arafat, Muhammad Rizwan Azhar, Yijun Zhong, Xiaomin Xu, Moses O. Tadé and Zongping Shao
{"title":"A bi-functional air electrode developed from a dual-MOF strategy for high-performance zinc–air batteries†","authors":"Yasir Arafat, Muhammad Rizwan Azhar, Yijun Zhong, Xiaomin Xu, Moses O. Tadé and Zongping Shao","doi":"10.1039/D4EY00008K","DOIUrl":null,"url":null,"abstract":"<p >A durable, high-performing and cost-effective bi-functional catalyst toward oxygen reduction/evolution reactions (ORR/OER) is the key towards the practical application of Zn–air batteries (ZABs). Here, we report a new concept of combining pristine and carbonized MOFs for developing a bifunctional electrocatalyst for ZABs, where the pristine MOF acts as a support for the OER catalysts and the carbonized MOF acts as the ORR catalyst and enhances the electronic conductivity. By electroless NiP-plating over the surface of the Fe-containing 3D MOF (MIL-100), the catalyst shows superior activity for the OER, delivering a current density of 10 mA cm<small><sup>−2</sup></small> at an overpotential of 295 mV together with a low Tafel slope of 62 mV dec<small><sup>−1</sup></small>. A 3D porous MOF serves as a substrate for growing NiP with maximal exposed active sites and the iron in the MOF interacts with NiP to further boost the intrinsic OER activity. Subsequently, we introduce carbonized ZIF-67 (C-ZIF-67) into NiP-MIL-100 to build a bifunctional catalyst, where C-ZIF-67 not only provides ORR catalytic activity but also creates a synergetic effect with NiP-MIL-100, and to expedite the charge/mass transfer. Using this air electrode for ZABs, an excellent bifunctionality with a small potential gap (0.78 V), a high peak power density (203 mW cm<small><sup>−2</sup></small>) and robust cycling over a period of 500 h were achieved.</p>","PeriodicalId":72877,"journal":{"name":"EES catalysis","volume":" 4","pages":" 968-979"},"PeriodicalIF":0.0000,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/ey/d4ey00008k?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"EES catalysis","FirstCategoryId":"1085","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/ey/d4ey00008k","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
A durable, high-performing and cost-effective bi-functional catalyst toward oxygen reduction/evolution reactions (ORR/OER) is the key towards the practical application of Zn–air batteries (ZABs). Here, we report a new concept of combining pristine and carbonized MOFs for developing a bifunctional electrocatalyst for ZABs, where the pristine MOF acts as a support for the OER catalysts and the carbonized MOF acts as the ORR catalyst and enhances the electronic conductivity. By electroless NiP-plating over the surface of the Fe-containing 3D MOF (MIL-100), the catalyst shows superior activity for the OER, delivering a current density of 10 mA cm−2 at an overpotential of 295 mV together with a low Tafel slope of 62 mV dec−1. A 3D porous MOF serves as a substrate for growing NiP with maximal exposed active sites and the iron in the MOF interacts with NiP to further boost the intrinsic OER activity. Subsequently, we introduce carbonized ZIF-67 (C-ZIF-67) into NiP-MIL-100 to build a bifunctional catalyst, where C-ZIF-67 not only provides ORR catalytic activity but also creates a synergetic effect with NiP-MIL-100, and to expedite the charge/mass transfer. Using this air electrode for ZABs, an excellent bifunctionality with a small potential gap (0.78 V), a high peak power density (203 mW cm−2) and robust cycling over a period of 500 h were achieved.