Carbon dots-derived three-dimensional-ordered macroporous host with high penetrability and catalytic activity for LSBs under lean electrolyte  

作　　者：Jiao-Zi Duan Hua-Yu Pei Quan Yang Xue Li Xin Ba Xue Yong Jun-Ling Guo Si-Yu Lu 

机构地区：[1]Green Catalysis Center,College of Chemistry,Zhengzhou University,Zhengzhou 450001,China [2]Country State Center for International Cooperation On Designer Low-Carbon&Environmental Materials,School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [3]Hubei Institute of Quality Supervision Inspection,Wuhan 430061,China [4]Department of Chemistry,University of Sheffield,Sheffeld S37HF,UK

出　　处：《Rare Metals》2024年第6期2560-2573,共14页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.52122308 and 52102318);Fellowship of China Postdoctoral Science Foundation(Nos.2021TQ0287 and 2022M722855)。

摘　　要：The practical energy density of lithium-sulfur batteries(LSBs)is seriously limited by the high electrolyte-to-sulfur ratios(E/S).The E/S can be reduced by employing hosts with easy-to-infiltrate structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress"shuttle effect"via accelerating the slow conversion of soluble poly sulfides to insoluble sulfides.Among the easy-to-infiltrate structures,the three-dimensional-ordered macroporous(3DOM)structure is easier to scale preparation and more suitable for the existing industrial processes.However,it is difficult to obtain the 3DOM with(1)high penetrability due to the high viscosity of frequently-used organic polymer precursors and(2)high catalytic activity due to the low confinement effect,meaning that uniformly dispersed small-sized catalytic materials are difficult to load on 3DOM.Herein,using carbon dots(CDs)with both organic and inorganic properties as a precursor and aggregation limiting agent,a 3DOM host with high penetrability and homodispersed Ni particles of small sizes(Ni-CDs-3DOM)was synthesized.In this host:(1)CDs precursor with suitable viscosity can improve the penetrability.(2)CDs can effectively inhibit the agglomeration of Ni particles.(3)Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur reactions.Consequently,the Ni-CDs-3DOM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading(5.5 mg·cm^(-2))and low E/S(6.5μl·mg^(-1)).This work indicates the usefulness of CDs in constructing hosts for LSBs with high energy density.

关 键 词：Lithium-sulfur batteries Carbon dots Catalytic action Easy-to-infiltrate structure Lean electrolyte 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ426[化学工程]