Si is regarded as the most promising anode material for lithium-ion batteries owing to its high theoretical capacity and low working voltage. Waste glass microfiber filters (GFs) can be an optimal silica resource for nanostructured Si synthesis because they do not require crushing or acid leaching procedures, which are essential for other silica resources. In this study, benefiting from the original filter shape, fibrous yolk-shell structured Si/carbon composite freestanding electrodes are fabricated via magnesiothermic reduction (MgR) and carbon coating processes using GFs not only as the silica precursor for MgR but also as the hard template for carbon coating. The carbon shell acts as a conductive framework for the freestanding electrodes and encapsulates the Si nanoparticles (Si NPs) inside the shell with a void space. The freestanding electrodes exhibit good cycling performance and a high areal capacity of 2.2 mA h cm−2 at the 150th cycle because of the yolk-shell structure, which accommodates the volume expansion of the Si NPs.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Ministry of Science and ICT ( 2019R1A2B5B02070203 ), and by Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by Ministry of Science and ICT ( 2018M3D1A1058744 ).
© 2020 Elsevier B.V.
- Freestanding electrode
- Glass microfiber filter
- Lithium-ion battery
- Magnesiothermic reduction
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering