The Synthesis Of Ni₂FeGa Alloy Nanowires By Electrodeposition And Its Magnetic Properties

Ni₂FeGa alloys have attracted much attention due to ts high saturation magnetization,good magnetocaloric effect and magnetoresistance effect.However,However,Ni₂FeGa alloy nanowires have not been successfully synthesized,and their basic physical properties are not yet known.Whether the Ni₂FeGa alloy still has the abundant physical properties of bulk material and whether there will be new properties under the one-dimensional scale is worth exploring.In this paper,Ni₂FeGa alloy nanowires were prepared by electrodeposition,and their structure and magnetic properties were characterized.For the preparation of nanowires,using sulfate as the main salt for electrodeposition,double electrodes as the electrode system,and constant current pulse as the deposition power source,Ni_53.6Fe_29.3Ga_17.1 and Ni_42.9Fe_30.7Ga_26.4 nanowires were prepared.The results show that it is difficult for Ga ions to co-deposit with Fe and Ni.Only when high Ga ion concentration(5-15 times of Ni²⁺,15-30 times of Fe²⁺)and high current density act simultaneously,the Ga content in the alloy can be made obvious Promote.The structure of the nanowire is the coexistence of two phases,one phase is the?phase(A1)with FCC structure,and the lattice constant a=3.67(?);the other phase is BCC structure(A2),the lattice constant a=2.87(?),and the average grain size is 5.6-11.6 nm,the coercivity H_c is 10-134 Oe.The coercivity is significantly affected by current density and deposition time,and the variation of remanence ratio and coercivity is basically the same.There is no martensitic transformation in the range of 80-370 K,and the Curie temperature T_c of all samples is greater than 370 K.The ferromagnetic resonance results show that the gyromagnetic ratio of Ni_54.2Fe_31.2Ga_14.6(NFG-8)is 33.99 GHz/T,the Lande g factor is 2.429,the Gilbert damping coefficient?is 0.018 3,M_s is 96.1 emu/cm³;K_eff is 0.031 7×10⁶ erg/cm³;Ni_44.1Fe_33.2Ga_22.8(NFG-6)has a gyromagnetic ratio of 27.95 GHz/T,a Lande g factor of 1.997,M_s of 101.4 emu/cm³,and K_eff of 0.034 7×10⁶ erg/cm³.