| Three-dimensional graphene material constructs a three-dimensional porous network structure through two-dimensional graphene sheets,and extends the excellent physical and chemical properties of graphene in the micro-size to three-dimensional macro-size materials.By controlling the pore orientation and pore wall structure of graphene,three-dimensional graphene has high elastic properties.At present,elastic three-dimensional graphene has attracted extensive attention in mechanical damping,energy storage,sensing,oil-water separation and other applications.Carbon nanotube（CNTs）is a kind of one-dimensional carbon nano-carbon material with large aspect ratio.The composite of CNTs and three-dimensional graphene can effectively increase the specific surface area of three-dimensional graphene,provide more load sites,and increase the contact area during compression/recovery,so that the comprehensive application performance of the composite is significantly improved.In this paper,CNTs were grown in situ in elastic graphene aerogel（EGA）.The orientation,length and growth density of CNTs were controlled by growth factors.The application of EGA/CNTs composites in energy storage,oil-water separation and other fields was further studied.The main research of this paper is as follows:（1）In order to improve the loading efficiency of the catalyst on the graphene wall and control the growth structure of CNTs,the surface treatment of the graphene pore wall in EGA was studied.Si O2 thin layer was in-situ coated on the graphene pore wall of EGA by hydrolysis pyrolysis process.Studies have shown that the Si O2 layer can be uniformly coated on the graphene wall when the volume of Si Cl4 precursor solution is 0.05 m L and the volume of C8H20O4Si is 0.05 m L.CNTs were in-situ grown on the surface-treated EGA by chemical vapor deposition（CVD）method,and the effects of CVD process parameters on the length and orientation morphology of CNTs were studied.The results show that the injection rate of carbon source/catalyst solution is the main factor affecting the orientation of CNTs,and the vertical CNTs array can be obtained when the injection rate reaches 20 m L/h.The injection time can significantly affect the length of CNTs,and the maximum growth length can reach 38μm.The compression/recovery test shows that the EGA can still maintain high elasticity after the growth of CNTs,the maximum recoverable compression deformation can reach 90%,and the stress retention rate can reach 90%after 1000compression/recovery.（2）Based on the large specific surface area,continuous conductive network and porous structure of EGA/CNTs,EGA/CNTs was used as electrode skeleton to load Mn O2for supercapacitor electrode.Mn O2 was in-situ loaded into EGA/CNTs aerogels by electrochemical deposition process.Micromorphology characterization showed that Mn O2 could be uniformly loaded on CNTs,and the load increased with the extension of deposition time.Compression/recovery test showed that Mn O2could maintain stable load during compression/recovery.The electrochemical performance test showed that the mass specific capacitance of EGA/CNTs-Mn O2 could reach 754 F·g-1.After assembled into a compressible symmetric electrode supercapacitor,the mass specific capacitance of its energy storage performance under 80%compression deformation can still maintain 97%,showing excellent compression resistance.Its volume specific capacitance reaches 32.6 F·cm-3,which is 465%higher than that of the uncompressed precursor.（3）EGA/CNTs were applied to oil-water separation,and their adsorption properties were studied by regulating the growth density and length of CNTs in EGA.Studies have shown that with the increase of CNTs growth density and growth length,the adsorption rate and adsorption capacity of the composites will be improved due to the increase of specific surface area and capillary channel of the composites.When the injection speed is 20 m L/h and the injection time is 20 min,the adsorption capacity of pump oil and oil can reach more than 65 times. |
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