Vanadium doped cobalt nickel spinel ferrite-based nanocomposite electrodes

1. A nanocomposite electrode, comprising:

a substrate;

at least one binding compound;

at least one carbonaceous compound; and

vanadium doped spinel ferrite nanoparticles (V-SFNPs);

wherein the V-SFNPs have a formula of Co x Ni 1-x V y Fe 2-y O z ;

wherein x=0.1-0.9, y=0.01-0.10, and z=3-5;

wherein the substrate is at least partially coated on a first side with a mixture comprising the V-SFNPs, the at least one binding compound, and the at least one carbonaceous compound.

2. The nanocomposite electrode of claim 1 , wherein the V-SFNPs have:

a substantially spherical shape;

an average size of 10-1000 nm.

3. The nanocomposite electrode of claim 1 , wherein the V-SFNPs comprises:

20-30 wt % oxygen, 1-10 wt % vanadium, 40-50 wt % iron, 10-20 wt % cobalt, and 10-20 wt % nickel, based on the total weight of the oxygen, vanadium, iron, cobalt, and nickel.

4. The nanocomposite electrode of claim 1 , wherein the mixture comprises:

1-20 wt. % of the V-SFNPs; and

80-99 wt. % of the binding compound, and the carbonaceous compound based on the total weight of the V-SFNPs, the binding compound, and the carbonaceous compound.

5. The nanocomposite electrode of claim 1 , having:

85-92 wt % carbon, 5-10 wt % oxygen, 0.1-2 wt % vanadium, 0.5-2 wt % iron, 0.5-1 wt % cobalt, and 0.5-1 wt % nickel, based on the total weight of the carbon, oxygen, vanadium, iron, cobalt, and nickel.

6. The nanocomposite electrode of claim 1 , wherein:

the binding compound is at least one selected from the group consisting of polyvinylidene fluoride and N-methyl pyrrolidone.

7. The nanocomposite electrode of claim 1 , wherein:

the carbonaceous compound is at least one selected from the group consisting of graphite, activated carbon, reduced graphene oxide, carbon nanotubes, carbon nanofibers, and carbon black.

8. The nanocomposite electrode of claim 1 , wherein:

the substrate is made from at least one material selected from the group consisting of stainless steel, aluminum, nickel, copper, platinum, zinc, tungsten, and titanium.

9. The nanocomposite electrode of claim 1 , wherein the V-SFNPs are made by a method comprising:

mixing a cobalt (II) salt, a nickel salt, an iron (III) salt, and a vanadium (III) salt in water to form a mixture;

adjusting the pH of the mixture to 10-12 with a base to form a basic mixture;

heating the basic mixture to 150-200° C. for 10-20 hours to form a powder; and

washing the powder with water and drying at a temperature of 60-80° C. to form the V-SFNPs.

10. A method of making the nanocomposite electrode of claim 1 , comprising:

mixing the binding compound and the carbonaceous compound for 1-4 hours at a temperature of 50-70° C. to form a paste;

adding 1-20 wt. % of the V-SFNPs, based on the total weight of the binding compound, the carbonaceous compound, and the V-SFNPs, into the paste and sonicating for 10-30 minutes creating a mixture;

coating the mixture onto the substrate to form the nanocomposite electrode; and

drying the nanocomposite electrode at a temperature less than 100° C.