Qingdao University successfully developed elastic graphene airgel
Among the many macro-structure of graphene, the graphene airgel (Graphene Aerogel) is one of the most compelling material. And a resilient graphene airgel, because of low density, high porosity, excellent mechanical properties and high conductivity, are widely used in the field of lightweight structural materials, energy storage material, a flexible electrically conductive material, the sensor and damping material . Material scientists have developed the current preparation of high resilience template method, a sol-gel method or the like graphene airgel. But the preparation of graphene can not be designed shape airgel, airgel graphene shape generally depends on the shape of the container. Recently, the right to Qingdao University professor Liu Jing, Li Chen Wei young teachers and researcher at the Institute of Chemistry Liuchen Yang, Australia Deakin University Professor Yang Wenrong al. cooperation , the trade melamine foam is expendable template, It retains the shape of the template utilizing a template graphene oxide to graphene network assembled, and then by etching away hydroiodic acid template, an ultra-resilient prepared graphene airgel having a complicated shape. Schematic diagram of the FIG. 1 In melamine foam as a template, the preparation of ultra-resilient graphene airgel (A); graphene airgel various shapes (BF ) and the three-dimensional graphene airgel composite structure (g). The airgel having a super-resilient, exhibits high compressive strength of 0.556 MPa at a strain rate of 95%. The airgel has excellent durability, a deformation of 90%, can withstand compressive hundreds of times – test responses. And the sample at a high temperature (400 deg.] C) and low temperature (-100 deg.] C) over its resilient properties are maintained. FIG. 2 Mechanical properties of graphene airgel characterize the graphene airgel exhibit superhydrophobic, for a variety of organic solvents, exhibits a high adsorption efficiency (176-513 g g-1). Ultra-resilient due to the sample, high mechanical properties and excellent heat resistance, solvent can be recovered or removed by suction or squeezing the burning, it can be reused adsorbed solvent. FIG. 3 Graphene airgel solvent adsorption test (AD); Adsorption – extrusion (e, g) and adsorption – combustion (f, h) cycling test .Due to the high conductivity of graphene airgel structure and an excellent stability, compression, bending and other deformation of the sample exhibits stable electrical response and sensitivity, can be assembled into a pressure / strain sensors. And it may be made of a flexible wearable period, directly affixed to the surface of the human body, the human body for detecting motion information of the wrist, and finger pulse. FIG. 4 Graphene airgel cylindrical assembly into a pressure / sensor (a) Schematic strain; alkenyl cylindrical graphite airgel compression cycle test (BD); graphene airgel film bending cycle test (E); airgel assembled into a flexible wearable device for detecting body motion: bending the wrist (f), the bending finger (g), pulse rate, and (h). This preparation is simple, high performance, easy to design the shape of graphene airgel important for industrial applications and expansion of such materials. Research results Superelastic and Arbitrary-Shaped Graphene Aerogels with Sacrifcial Skeleton of Melamine Foam for Varied Applications was published in on Advanced Functional Materials.