1 research outputs found
Fabricating 3D Macroscopic Graphene-Based Architectures with Outstanding Flexibility by the Novel Liquid Drop/Colloid Flocculation Approach for Energy Storage Applications
Inspired by “water
ripples” in nature and the flocculation phenomenon in colloid
chemistry, a novel liquid drop/colloid flocculation approach is developed
to fabricate an extremely flexible and compressible 3D macroscopic
graphene-based architecture (hydrogels or aerogels), via a new coagulation-induced
self-assembly mechanism. This facile and universal technique can be
achieved in a neutral, acidic, or basic coagulation bath, producing
microsized hydrogels with various structures, such as mushroom, circle,
disc shapes, etc. The method also allows us to introduce various guest
materials in the graphene matrix using transition metal salts as the
coagulating bath. A mushroom-shaped NiCo oxide/GS hybrid aerogel (diameter:
3 mm) is prepared as an example, with ultrathin NiCo oxide nanosheets
in situ grown onto the surface of graphene. By employing as binder-free
electrodes, these hybrid aerogels exhibit a specific capacitance of
858.3 F g<sup>–1</sup> at 2 A g<sup>–1</sup>, as well
as a good rate capability and cyclic stability. The asymmetric supercapacitor,
assembling with the hybrid aerogels as cathode and graphene hydrogels
as anode materials, could deliver an energy density of 21 Wh kg<sup>–1</sup> at power density of 4500 W kg<sup>–1</sup>. The ease of synthesis and the feasibility of obtaining highly flexible
aerogels with varied morphologies and compositions make this method
a promising one for use in the field of biotechnology, electrochemistry,
flexible electronics, and environment applications