In‐Situ Growth of Mn3O4 Nanoparticles on Nitrogen‐Doped Carbon Dots‐Derived Carbon Skeleton as Cathode Materials for Aqueous Zinc Ion Batteries

• Published in: ChemSusChem Vol. 15; no. 6
• Main Authors: Song, Tian‐Bing, Huang, Zun‐Hui, Niu, Xiao‐Qing, Zhang, Xi‐Rong, Wei, Ji‐Shi, Xiong, Huan‐Ming
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 22.03.2022
• Subjects: Carbon; Carbon content; Carbon dots; cathode material; Cathodes; Electrode materials; Electrodes; Energy storage; Manganese oxides; Mn3O4; nanocomposite; Nanocomposites; Nanomaterials; Nanoparticles; Nitrogen; Rechargeable batteries; Synthesis; zinc ion battery
• DOI: 10.1002/cssc.202102390
• ISSN: 1864-5631

Mn3O4 is a promising cathode material for aqueous zinc ion batteries (ZIBs) which is a new type of low cost, eco‐friendly, high security energy storage system, while those previously reported electrochemical capacities of Mn3O4 are far from its theoretical value. In this work, Mn3O4 nanoparticles and nitrogen‐doped carbon dots (NCDs) are synthesized together through an in‐situ hydrothermal route, and then calcined to be a nanocomposite in which Mn3O4 nanoparticles are anchored on a nitrogen‐doped carbon skeleton (designated as Mn3O4/NCDs). Although the carbon content is only 3.9 wt.% in the Mn3O4/NCDs, the NCDs‐derived carbon skeleton provides an electrically conductive network and a stable structure. Such a special nanocomposite has a large specific surface area, plenty of active sites, excellent hydrophilicity and good electronic conductivity. Owing to these structural merits, the Mn3O4/NCDs electrode exhibits a preeminent specific capacity of 443.6 mAh g−1 and 123.3 mAh g−1 at current densities of 0.1 and 1.5 A g−1 in ZIBs, respectively, which are far beyond the bare Mn3O4 nanoparticles synthesized under the similar condition. The electrochemical measurement results prove that carbon dots, as a new type of carbon nanomaterials, have strong ability to modify and improve the performance of existing electrode materials, which may push these electrode materials forward to practical applications. Incorporating carbon for better cathode: Mn3O4 nanoparticles grew in situ on nitrogen‐doped carbon skeleton derived from carbon dots, generating Mn3O4/NCDs nanocomposite as high‐performance cathode material, which exhibits improved electrochemical properties for aqueous zinc ion batteries.