Mesoporous graphene-layered double hydroxides free-standing films for enhanced flexible supercapacitors

Two-dimensional graphene materials as supercapacitors electrode have attracted tremendous attention owing to their high surface area and exceptionally electrical conductivity, while it is still a great challenge to achieve desired mesoporous graphene electrodes as the easy aggregation of graphene nanosheets. Here we report the design and fabrication of mesoporous free-standing reduced graphene oxide (rGO)based films by introducing layered double hydroxides (LDHs) nanoplatelets into the interlayer of rGO nanosheets. The nanostructures regular evolutions of rGO/COAL-LDH free-standing film due to the embedding of LDHs were rationally investigated with detail experiments. Moreover, the flexible all solid-state asymmetric supercapacitor device fabricated by using rGO/CoAl-LDH as positive electrode demonstrates a superior performance compared to most reported rGO-based free-standing film electrodes. The results presented here provide valuable insights into exploring mesoporous graphene-based free-standing architectures for highly-efficient and stable energy storage devices. (C) 2015 Elsevier B.V. All rights reserved.