Flexible and stable 3D lithium metal anodes based on self-standing MXene/COF frameworks for high-performance lithium-sulfur batteries

Abstract

Lithium metal (Li) is believed to be the ultimate anode for lithium-ion batteries (LIBs) owing to the advantages of high theoretical capacity, the lowest electrochemical potential, and light weight. Nevertheless, issues such as uncontrollable growth of Li dendrites, large volume changes, high chemical reactivity, and unstable solid electrolyte interphase (SEI) hinder its rapid development and practical application. Herein a stable and dendrite-free Li-metal anode is obtained by designing a flexible and freestanding MXene/COF framework for metallic Li. COF-LZU1 microspheres are distributed among the MXene film framework. Lithiophilic COF-LZU1 microspheres as nucleation seeds can promote uniform Li nucleation by homogenizing the Li + flux and lowering the nucleation barrier, finally resulting in dense and dendrite-free Li deposition. Under the regulation of the COF-LZU1 seeds, the Coulombic efficiency of the MXene/COF-LZU1 framework and electrochemical stability of corresponding symmetric cells are obviously enhanced. Li-S full cells with the modified Li-metal anode and sulfurized polyacrylonitrile (S@PAN) cathode also exhibited a superior electrochemical performance.

A Novel Material for High‐Performance Li–O2 Battery Separator: Polyetherketone Nanofiber Membrane

“…Beside these general properties, the structural characteristics of the separator (including pore size, pore size distribution, porosity, and thickness) affects the transportation of Li + in the separator, as well as at the interface between the separator and the electrode. [ 18 ] This further affects the lithium nucleation process during electroplating and ultimately determines the ease of lithium dendrite formation. [ 2b ] The pore sizes, pore size distributions, porosity, and thickness of the three separators are characterized, as shown in Figure a–c.…”

Combining metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs): Emerging opportunities for new materials and applications

“…Currently, numerous studies have shown that MOF-based hybrid materials could afford multifunctional properties via hybridization with other functional materials (e.g., metal nanoparticles [113][114][115][116], polymers [117,118], and other MOFs [119,120]. Similarly, combining functional components with COFs to obtain COF-based hybrid materials has also attracted widespread concerns [121][122][123][124][125][126]. Recently, researchers have successfully achieved the hybridization of MOFs and COFs, which can be further divided into two categories: MOF@COF hybrid materials synthesized by introducing the prepared MOFs into the synthetic system of COFs and COF@MOF hybrid materials prepared via the growth of additional MOFs outside/inside the pre-synthesized COFs.…”

On the occasion of the 80th birthday of Professor Yitai Qian: Celebrating 60 years of innovation in solid-state chemistry and nanoscience

“…In terms of structural design, Guihua Yu from University of Texas at Austin provides a comprehensive overview on the fabrication, advances, and challenges of vertically aligned 2D material electrodes for scalable energy storage systems [43]. Jinkui Feng from Shandong University demonstrates a flexible and freestanding MXene/COF framework to stabilize the Li anode in Li-S battery [44]. Zhaoping Liu from Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences reports porous carbon nitride microspheres as uniform lithophilic coatings on Cu/Li foils to achieve dendrite-free lithium plating [45].…”