Preparation,Characterization And Supercapacitor Property Of Nickel Phosphide/Carbon-Based

Metal phosphide nickel?Ni₂P?has metalloidity and high electronic conductivity,but the material also has corresponding disadvantages,such as large volume effect and poor stability.Studies have shown that carbon materials have good cycle stability and small changes in volume effect,but the theoretical capacitance of the material is low.Therefore,it is of great scientific significance to combine the research of nickel phosphide and carbon materials.This topic mainly starts from the following aspects:1.Preparation,Characterization and Electrochemical Properties in Supercapacitor of Nickel Phosphate/Graphene?Ni₂P/rGO?CompositesNi₂P/rGO composites were prepared by solvothermal method under the action of CTAB with nickel chloride?NiCl₂.6H₂O?and yellow phosphorus?YP₄?as reactants,ethylenediamine and ethylene glycol as mixed solvents.Through a series of characterizations,30 nm of Ni₂P nanoparticles were uniformly and firmly attached to the surface of the graphene sheets.As a supercapacitor electrode material,by performing electrochemical performance tests on it,the discharge specific capacitance was 1680 F/g when the current density was 0.5A/g.The specific capacity of Ni₂P/rGO composites is maintained at 90%of the initial specific capacitance after circulating 2500 cycles at a current density of0.5 A/g,which means that the prepared Ni₂P/rGO composites have better stability.2.Preparation,Characterization and Electrochemical Properties in Supercapacitor of Nickel Phosphate/Carbon Nanotubes?Ni₂P/MWCNTs?CompositesFirstly,the multi-walled carbon nanotubes are pretreated,and then the pretreated multi-walled carbon nanotubes,nickel nitrate and yellow phosphorus are used as the reaction raw materials by using the solvothermal method,and ethylene glycol and tetraethylenetriamine are mixed solvents.Ni₂P/MWCNTs composites were synthesized in one step at 160? for 10 h.Ni₂P and multi-walled carbon nanotubes interacted to form a stable flower-like structure.By further characterizing the Ni₂P/MWCNTs for phase analysis and electrochemical performance testing of supercapacitors,the results shows that the discharge specific capacitance of the flower-shaped Ni₂P/MWCNTs at a current density of 0.5 A/g can reach 1210 F/g by electrochemical tests.3.Preparation,Characterization and Supercapacitor Properties of Nickel Phosphate/Carbon?Ni₂P/C?CompositesThe core-shell Ni₂P/C composites were successfully synthesized by solvothermal method using isopropyl alcohol,ethylenediamine and H₂O as mixed solvents,nickel nitrate,yellow phosphorus,sucrose and urea as raw materials.By characterization,the composite material has a core-shell structure composed of Ni₂P as a core and carbon as a shell.By adjusting the reaction conditions,the performance and morphology of Ni₂P/C composites reached the optimum state when the reaction temperature was 180?,the reaction time was10 h,and the urea addition amount was 1.0 g.Under this condition,Ni₂P/C was obtained.The composite material was tested for electrochemical performance of supercapacitor.It was found by electrochemical performance test that the discharge time of Ni₂P/C core-shell composite at current density of 0.5 A/g can reach 1120 s,and the calculated specific discharge capacitance is 1120 F/g.