Methods of forming metal nanomaterials

A method of forming a metal nanomaterial, comprising;

• forming an aqueous precursor solution comprising a metal precursor and a metal oxide precursor;
• adding a complexing agent to the aqueous precursor solution;
• hydrolyzing the metal precursor and the metal oxide precursor to form a sol;
• heating the sol to form a gel;
• calcining the gel to incorporate metal cations from the metal precursor into a metal oxide lattice from the metal oxide precursor;
• exposing the calcined gel to a reducing agent to exsolve the metal from the metal oxide lattice;
• and
• forming the metal nanomaterial comprising an iridium/samarium-doped ceria material, a particle size of the metal in the metal nanomaterial being substantially uniform and determined by an amount of the complexing agent added to the aqueous precursor solution and the amount of the complexing agent controlling a hydrolysis rate of the metal cations in the aqueous precursor solution.

A method of forming a metal nanomaterial, comprising;

• forming an aqueous precursor solution comprising a metal precursor and a metal oxide precursor;
• adding a complexing agent to the aqueous precursor solution;
• hydrolyzing the metal precursor and the metal oxide precursor to form a sol;
• heating the sol to form a gel;
• calcining the gel to incorporate metal cations from the metal precursor into a metal oxide lattice from the metal oxide precursor;
• exposing the calcined gel to a reducing agent to exsolve the metal from the metal oxide lattice;
• and
• forming the metal nanomaterial comprising a ruthenium/lanthanum-doped ceria material, a particle size of the metal in the metal nanomaterial being substantially uniform and determined by an amount of the complexing agent added to the aqueous precursor solution and the amount of the complexing agent controlling a hydrolysis rate of the metal cations in the aqueous precursor solution.

A method of forming a metal nanomaterial, comprising;

• providing an aqueous precursor solution comprising a metal precursor, a metal oxide precursor, and a complexing agent, the metal oxide precursor comprising a samarium salt and a cerium salt;
• hydrolyzing the metal precursor and the metal oxide precursor to form a sol;
• incorporating metal cations of the metal precursor into a metal oxide of the metal oxide precursor;
• and
• exsolving the metal cations to form a metal nanomaterial comprising a metal and the metal oxide, the metal of the metal nanomaterial exhibiting a substantially uniform size, a particle size of the metal in the metal nanomaterial determined by an amount of the complexing agent added to the aqueous precursor solution and the amount of the complexing agent controlling a hydrolysis rate of the metal cations in the aqueous precursor solution.

A method of forming a metal nanomaterial, comprising;

• adding a complexing agent to an aqueous precursor solution comprising a metal precursor and a metal oxide precursor, the metal precursor comprising a metal salt including iridium;
• hydrolyzing the metal precursor and the metal oxide precursor to form a sol;
• incorporating metal cations of the metal precursor into a metal oxide of the metal oxide precursor;
• and
• calcining the metal cations to form a metal nanomaterial comprising the metal and the metal oxide, the metal comprising a predetermined substantially uniform particle size, a particle size of the metal in the metal nanomaterial determined by an amount of the complexing agent added to the aqueous precursor solution and the amount of the complexing agent controlling a hydrolysis rate of the metal cations in the aqueous precursor solution.

A method of forming a metal nanomaterial, comprising:

• forming an aqueous precursor solution comprising a metal precursor and a metal oxide precursor;
• adding a complexing agent to the aqueous precursor solution;
• hydrolyzing the metal precursor and the metal oxide precursor to form a sol;
• heating the sol to form a gel;
• calcining the gel to incorporate metal cations from the metal precursor into a metal oxide lattice from the metal oxide precursor, the metal oxide lattice comprising ceria (CeO2), samarium doped ceria (SDC), or lanthanum doped ceria (LDC);
• exposing the calcined gel to a reducing agent to exsolve the metal from the metal oxide lattice;
• and
• forming a metal nanomaterial comprising a metal and a metal oxide, a particle size of the metal in the metal nanomaterial determined by an amount of the complexing agent added to the aqueous precursor solution and the amount of the complexing agent controlling a hydrolysis rate of the metal cations in the aqueous precursor solution, the metal exhibiting a substantially uniform particle size.