▎ 摘　　要

Constructing highly conductive and mechanically robust graphene foams remains a great challenge for practical applications. Herein, we report a facile fabrication of covalently cross-linked graphene foam (CCGF) by C-N bonds with superb electromechanical properties. Benefiting from covalent bonds-enhanced effect and removal of oxygen-containing groups of GO sheets, the resulting CCGFs exhibit an excellent compressibility and conductivity. More importantly, the CCGFs exhibit tunable conductivity at different compressed strains and ultrasensitive stress responsivity (0.046 kPa(-1) in the regime of 3.5-5 kPa), featuring huge prospects for elastic conductive and ultrasensitive sensing applications. The proposed strategy may enlighten the fabrication of novel materials via cross-linking for other related applications. (c) 2019 Elsevier Ltd. All rights reserved.