Towards High-Performance Future of Batteries—The Critical Effects of Metal-Organic-Framework (MOF)-Based Materials on the Electrodes, Electrolytes and Separators

In this work, we present our recent study on the critical effects of metal-organic frameworks (MOF) materials on the most important components of batteries, including electrodes, electrolytes, and separators. Firstly, a novel MOF/Ionic liquid-based solid-state electrolyte (HKUST-1@IL-Li) is designed by immobilizing ionic liquid ([EMIM][TFSI]) in the nanopores of HKUST-1 MOFs. 3D angstrom-level ionic channels of the MOF host can restrict electrolyte anions and act as “highways” for fast Li⁺ transport. A high ionic conductivity (6.85 × 10^-⁴ S/cm) and excellent thermal stability of the HKUST-1@IL-Li electrolyte is achieved and as-fabricated LiFePO₄/HKUST-1@IL-Li/Li solid-state battery exhibits remarkable performance at high temperature (100 °C). In addition, MOF-derived Co-doped carbon nanosheets are fabricated as cathode hosts for lithium-sulfur batteries (LSBs). Reduced Co nanoparticles evenly distributed on the nanosheets showing the catalytic effect can promote polysulfide conversion. After decorating the carbon nanosheets with DNA molecules, 3D Li₂S nucleation and deposition are realized in a high-sulfur-loaded LSB. A high areal capacity of 8.1 mA h cm⁻² is achieved for the LSB with a high sulfur load of 10 mg cm⁻², which is more than 2 times that of commercial Li-ion batteries. Finally, a MOF/CNT@DNA-Janus interlayer fabricated for LSBs achieves “shuttle effect” suppression and lithium dendrite-free simultaneously. Li⁺transfers through the pathway inside the MOF layer then evenly deposited on the Li anode, which efficiently suppresses the Li dendrites growth. Meanwhile, the experimental evidence combined with theoretical computation of DFT calculations proves that the functional groups on the CNT@DNA layer, such as –P=O and = N–show high adsorption strengths to anchor and block polysulfides. All the research works demonstrate that metal-organic frameworks can be desirable materials for next-generation batteres.<br/><b>Acknowledgment:</b> This work was supported by the National Research Foundation of Korea (NRF-2021R1A2C1008272). This study was supported by Ministry of Trade, Industry and Energy, KEIT, under the project title "International standard development of evaluation methods for nano-carbon-based high-performance supercapacitors for electric vehicles" (project # 20016144). This work was supported by Korean Ministry of Industry, KEIT, "Setting and Developing Key Technology Standards Strategy and Development for Global Competitiveness on Materials, Parts, and Equipments" (project # 20015943).