Transition metal electrochemical catalyst prepared using ultrafast combustion method, and synthesis method therefor
A method for preparing a transition metal electrochemical catalyst according to an embodiment of the present disclosure includes dissolving a nitrogen precursor and a transition metal precursor in a polyol-based solvent so as to prepare a solution in which transition metal ions and free anions are coordinated, and mixing same with a support so as to prepare a mixture, igniting the mixture so as to carbonize the polyol-based solvent, thereby forming transition metal nanoparticles encompassed by carbon, performing heat treatment in order to carbonize remaining organic matter contained in the mixture, and removing, through acid treatment, impurities and transition metal nanoparticles not encompassed by carbon, and then removing remaining acid through washing and additional heat treatment, thereby a nanocatalyst having a structure in which a single-atom transition metal-nitrogen bonding structure and/or transition metal nanoparticles encompassed by carbon exist is synthesized.
1 . A method of synthesizing a transition metal electrochemical catalyst, the method comprising:
dissociating a nitrogen precursor and a transition metal precursor in a polyol-based solvent so as to prepare a solution in which transition metal ions and free radical anions are coordinated, and mixing the solution with a support so as to prepare a mixture;
igniting the mixture having been prepared in step a) so as to carbonize the polyol-based solvent, thereby forming transition metal nanoparticles encompassed by carbon;
performing heat treatment in order to carbonize remaining organic matter contained in the mixture; and
removing, through acid treatment, impurities and transition metal nanoparticles not encompassed by carbon, and then removing remaining acid through washing and reheat treatment, whereby a nanocatalyst having a structure in which a single-atom transition metal-nitrogen bonding structure and/or transition metal nanoparticles encompassed by carbon exists is synthesized.
2 . The method of claim 1 , wherein the polyol-based solvent is any one selected from the group consisting of tetraethylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, and butylene glycol.
3 . The method of claim 1 , wherein the nitrogen precursor is a monomer of multi-ring structure containing nitrogen, and is 1,10-phenanthroline, 1,10-phenanthroline-5-amine, or 2,2-bipyridine.
4 . The method of claim 1 , wherein the support is any one selected from the group consisting of is carbon black, graphene, carbon nanotubes, carbon nanofibers, silica (SiO2), titania (TiO2), zirconium oxide (ZrO2), polyaniline, polypyrrole, and silicon carbide (SiC).
5 . The method of claim 1 , wherein the transition metal precursor and the nitrogen precursor are mixed in a molar ratio of 1:0.5 to 1:10.
6 . The method of claim 1 , wherein the support and the polyol-based solvent are mixed in a mass ratio of 1:2 to 1:60.
7 . The method of claim 1 , wherein the transition metal precursor is a transition metal in the 3rd to 5th periods.
8 . The method of claim 1 , wherein the igniting is performed by blocking a combustion condition in order to control the degree of carbonization of the polyol-based solvent and the degree of oxidation of the transition metal.
9 . The method of claim 1 , wherein the heat treatment is performed at a temperature of 500° C. to 1,000° C. for 30 minutes to 12 hours under a flow of inert gas or ammonia gas.
10 . The method of claim 9 , wherein the inert gas is any one selected from the group consisting of nitrogen (N2), argon (Ar), helium (He), a mixed gas of inert gas and hydrogen (H2), and ammonia gas.
11 . The method of claim 1 , wherein the acid treatment is performed at a temperature of 0° C. to 90° C. for 30 minutes to 12 hours.
12 . A transition metal electrochemical catalyst synthesized by the method according to claim 1 .