A Pyrolysis‐Free Method Toward Large‐Scale Synthesis of Ultra‐Highly Efficient Bifunctional Oxygen Electrocatalyst for Zinc‐Air Flow Batteries. Issue 21 (1st May 2022)

• Record Type: Journal Article
• Authors: Li, Xueli; Liu, Di; Liu, Qingbin; Xiang, Zhonghua
• Is Part Of: Small. Volume 18:Issue 21(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-01
• Subjects: bifunctional oxygen catalysts -- covalent organic polymers -- large‐scale preparation -- pyrolysis‐free -- zinc‐air flow batteries; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202201197
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: The transition‐metal nitrogen‐carbon (M‐N‐C) catalysts, as one of the optimal bifunctional oxygen catalysts, are vital for cathodic oxygen electrode of Zn‐based air flow batteries (ZAFBs). However, chemical complexity of M‐N‐C catalysts prepared via the traditional pyrolytic process increases the difficulties of precise control toward configuration and repeatability, especially in large‐scale synthesis. Herein, a bifunctional oxygen catalyst via a pyrolysis‐free approach based on closed π‐conjugated covalent organic polymers (COPs, microwave synthesis) is developed, which inherits the advantage of the well‐defined configuration in an atomic manner. Profited from distinct catalytic centers and strong electronic coupling at the interface between COP and layered double hydroxides, the as‐synthesized catalyst not only more easily permits large quantity production (>1 kg per batch), but also maintains an ultrahigh bifunctional activity and a long cycle stability even after scale synthesis (Δ E [ E j10 – E 1/2 ] = 591 mV; energy efficiency drops by only 2.02% after 1200 cycles), which overwhelmingly exceeds the benchmark Pt/C+IrO2 and the state‐of‐the‐art pyrolytic bifunctional M‐N‐C oxygen catalysts. Abstract : A structurally well‐defined bifunctional oxygen catalyst is prepared via a pyrolysis‐free approach. The as‐synthesized catalyst more easily permits large quantity production while maintaining ultrahigh bi‐functional catalyst activity, overwhelmingly exceeding the benchmark Pt/C+IrO2 and the state‐of‐the‐art pyrolytic M‐N‐C catalysts.