Facile Synthesis of Hierarchical Porous Carbon Monolith: A Free-Standing Anode for Li-Ion Battery with Enhanced Electrochemical Performance

Abstract

Hierarchical porous carbon aerogel with a continuous three-dimensional framework has been synthesized via evaporation induced, coassembly based sol–gel polymerization of organic and inorganic precursors, for application as the anode in a Li-ion battery. A combination of resorcinol (R) and formaldehyde (F) as organic precursors and hybrid silica sources composed of TEOS (tetraethyl orthosilicate), APTES (3-aminopropyl triethoxysilane) and APTEMS (3-aminopropyl trimethoxysilane) as inorganic precursors has been used to obtain the porous carbon monolith. The porosity of the carbon aerogel has been tuned by varying the ratio of APTES/APTEMS. Postpyrolysis, the etching of the composite to remove silica network resulted in the formation of a high specific surface area (BET ∼ 2600 m2 g–1) carbon containing the distribution of micro-, meso- and macroporous domains. The electrode exhibits a high reversible capacity of 890 mAh g–1 after 100 cycles at a current density of 50 mA g–1.