Lithium Storage Behavior of Three-Dimensional Graphene-like Ordered Microporous Carbon Synthesized in a Zeolite Template

Abstract

Nanostructured carbons with high porosity are of great interest as high-performance anode materials for lithium-ion battery (LIB) applications. In the present work, we investigated the Li storage behavior of three-dimensional graphene-like ordered microporous carbon, which was synthesized via a zeolite-templating route. The microporous carbon exhibited an extremely high initial Li storage capacity as an anode for LIBs. Approximately 60% of the initial capacity was reversible during the subsequent cycles, while 40% was irreversible. The reversible capacity was comparable to the highest value reported so far with carbon alone. In order to investigate the chemical state of the Li species (i.e., ionic or metallic), the charged and discharged zeolite-templated carbon sample was characterized with 7Li nuclear magnetic resonance spectroscopy. The location of lithium was investigated using a transmission electron microscope equipped with an electron energy loss spectrometer and an energy-dispersive X-ray spectrometer. The result indicated that most of the reversible and irreversible lithium existed in nonmetallic +1 oxidation state inside the carbon micropores. The huge amount of Li storage is attributed to the three-dimensionally ordered microporous structure with a large surface area built with the single-layer graphene-like framework. In this study, we provides insights on the Li storage behavior in narrow carbon pore environment.