Synthesis Of Graphene Based Two-Dimensional Hybrids For Energy Storage And Conversion

Due to the large specific surface area,good electrical and mechanical properties,graphene has been widely used in energy storage and conversion.However,the application of graphene was limited by its low density of active sites,so scientists began to do some research of graphene-based composites,and achieved gratifying results.In this work,based on existing research achievements and aiming at solving controllable prepare graphene-based materials,an efficient strategy was proposed.The main contents and details are list as follows:1.Interfacial polymerization approach towards GO@PANI:An interfacial strategy was developed for r preparation of GO@PANI by using template,aniline as monomer.Interfacial polymerization is a slow and self-assemble process,as-prepared PANI exhibit greater linearization of polymeric chain and the PANI can be growth on the graphene uniformly,which are favor electrical conductivity.Furthermore,the thickness and anchored ions of GO@PANI can be controlled by adjust the ratio of aniline and doped acid.2.Synthesis of metal phosphides anchored graphene hybrids for energy storage and conversion:Iron cation-(Fe³⁺)and phosphate anion-(PO₄^3-)anchored PANI nanosheets?GO@?Fe|P?PANI??can easily be produced by using H₃PO₄ as an acid dopant and dissolving FeCl₃ in the aqueous layer.After direct pyrolysis under hydrogen atmosphere,diiron phosphide-embeddedandnitrogen-dopedporouscarbonnanosheets?RG@?Fe₂P?NPC??can be easily produced by using GO@?Fe|P?PANI?as a precursor.The obtained RG@?Fe₂P?NPC?show a high specific surface area,exhibiting outstanding performance for supercapacitor and electrochemical catalysis.Using such GO@?Fe|P?PANI?as precursor can further promise the uniform distribution of Fe₂P nanoparticles and form protected carbon layer around the nanoparticles,which will strength the interaction between graphene and nanoparticles,therefore enhanced the performance of materials.By altering the metal cations in aqueous layer,other kinds of metal phosphides or dual metal phosphides embedded carbon nanosheets can be easily prepared and show excellent electrochemical properties.3.Molybdenum-carbide-anchored nitrogen-doped porous carbon nanosheets as ultraefficient electrocatalysts for hydrogen evolution reaction:Herein,we employ Mo-anchored PANI nanosheets as precursors to prepare Molybdenum-carbide-anchored nitrogen-doped porous carbon nanosheets?Mo₂C@2D-NPC?.The as-fabricated 2D hybrid nanosheets possessed evenly distributed Mo₂C nanoparticles and high specific surfaces,indicating the presence of abundant exposed active sites for electrocatalysis.As a catalyst for electrocatalytic HER in alkaline media,Mo₂C@2D-NPC exhibited a low onset overpotential of 0 mV,an overpotential of only 45 mV at a current density of 10 mA cm^-2,and a small Tafel slope of 46 mV dec^-1.Such high electrocatalytic HER activity is comparable to that of commercial Pt/C,and superior to all of the previously reported Mo₂C-based catalysts.Density functional theory calculations were conducted to improve the understanding of the mechanism of the extremely high HER activity of Mo₂C@2D-NPC electrocatalysts.