Preparation method and use of high-entropy alloy (HEA)@carbon fiber composite nanomaterial
Provided are a preparation method and use of a high-entropy alloy (HEA)@carbon fiber composite nanomaterial. Five or more metal salts of different metal elements are dissolved in an organic solvent, a complexing agent is added to obtain a mixture, and then the mixture is stirred to obtain a mixed metal salt solution. A polymer is added to the mixed metal salt solution, and dissolved by stirring to obtain an electrospinning precursor solution. The electrospinning precursor solution is transferred into a syringe and the syringe and a syringe needle is kept free of air bubbles, and electrospinning is then conducted to obtain a precursor fiber membrane. The precursor fiber membrane is subjected to vacuum drying, a resulting dried sample is subjected to pre-sintering, and a resulting pre-sintered sample is then subjected to calcination to obtain the HEA@carbon fiber composite nanomaterial.
1 . A method for preparing a high-entropy alloy (HEA)@carbon fiber composite nanomaterial, comprising:
(1) dissolving five or more metal salts of different metal elements in an organic solvent, adding a complexing agent to obtain a mixture, and then stirring the mixture at room temperature until the metal salts and the complexing agent are dissolved to obtain a mixed metal salt solution;
(2) adding a polymer to the mixed metal salt solution obtained in step (1), dissolving by stirring, with a dissolution temperature of 20° C. to 80° C. and a dissolution time of 4 h to 36 h, to obtain an electrospinning precursor solution;
(3) transferring the electrospinning precursor solution obtained in step (2) into a syringe and keeping the syringe and a syringe needle free of air bubbles, and then conducting electrospinning to obtain a precursor fiber membrane; and
(4) subjecting the precursor fiber membrane obtained in step (3) to vacuum drying at a temperature of 40° C. to 80° C. for 12 h to 24 h, subjecting a resulting dried sample to pre-sintering in an air atmosphere, and then subjecting a resulting pre-sintered sample to calcination in an inert atmosphere to obtain the HEA@carbon fiber composite nanomaterial; wherein
the electrospinning in step (3) is conducted under the following conditions: a positive voltage of 17 kV to 25 kV, a negative voltage of −0.5 kV to −2.0 kV, a syringe needle model of 23 to 20, a distance between the syringe needle and a receiver of 8 cm to 20 cm, a propulsion speed of 0.3 mm/min to 2.5 mm/min, an ambient temperature of 25° C. to 60° C., and an ambient humidity of 10% to 40%; and
an aluminum foil or a silicone paper is used as the receiver, a receiving is achieved by one process selected from the group consisting of flat plate receiving and roller receiving, and during the receiving, a Taylor cone at a front end of the syringe needle remains stable without bifurcation.
2 . The method of claim 1 , wherein in step (1), the metal salts each are at least one selected form the group consisting of a chloride, a nitrate, a carbonate, a sulfate, and an organic salt, and
a metal element in the metal salts is selected from the group consisting of tin, antimony, germanium, iron, cobalt, nickel, chromium, manganese, copper, zinc, titanium, vanadium, molybdenum, tungsten, magnesium, aluminum, and indium.
3 . The method of claim 2 , wherein in step (1), the metal salts in the mixed metal salt solution have a total molar concentration of 0.1 mol/L to 1.2 mol/L, and
all metal elements in the metal salts have a total atomic proportion of 100%, with a percentage of each metal element ranging from 5% to 35%.
4 . The method of claim 1 , wherein the complexing agent is at least one selected from the group consisting of citric acid, sodium citrate, potassium pyrophosphate, acetylacetone, diethanolamine, sodium alginate, and oxalic acid, and
the complexing agent in the mixed metal salt solution has a molar concentration of 0.1 mol/L to 0.8 mol/L.
5 . The method of claim 1 , wherein the organic solvent is at least one selected from the group consisting of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), tetrahydrofuran (THF), dimethylacetamide (DMA), acetone, isopropanol, hexafluoroisopropanol (HFIP), and anhydrous ethanol.
6 . The method of claim 1 , wherein in step (2), the polymer is at least one selected from the group consisting of polyacrylonitrile (PAN), polyvinylpyrrolidone (PVP), polypropylene glycol (PPG), polystyrene (PS), polybenzimidazole (PBI), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyetherimide (PEI), polyvinylidene fluoride (PVDF), and polyvinyl acetate (PVA), and
a ratio of a mass of the polymer to a total molar number of all metal elements in the metal salts is in a range of 0.2 g:1 mol to 0.2 g:2 mol.
7 . The method of claim 1 , wherein in step (4), the pre-sintering in the air atmosphere is performed by heating to a temperature of 200° C. to 280° C. at a first heating rate of 1° C./min to 5° C./min and holding for 1 h to 3 h, and
the calcination in the inert atmosphere is performed by heating to a temperature of 600° C. to 1,200° C. at a second heating rate of 1° C./min to 10° C./min and holding for 2 h to 5 h.