Nanostructured mixed metal oxides as catalysts and method of making thereof

A method of forming a metal oxide material having a rod shape or a polyhedral nanostructure;

• the method comprising:
• preparing a first reverse micro-emulsion system comprising a precipitating agent dispersed in a first aqueous medium;
• preparing a second reverse micro-emulsion system containing a metal salt dispersed in a second aqueous medium, wherein preparing the second reverse micro-emulsion system includes ultrasonicating to obtain a transparent micro-emulsion suspension of the metal salt dispersed in the second aqueous medium;
• combining the first and second reverse micro-emulsions together to initiate a reaction;
• allowing the reaction to continue for a predetermined amount of time to form a product mixture comprising a metal oxide gel and the first and second aqueous media;
• separating the metal oxide gel from the first and second aqueous media;
• collecting the metal oxide gel;
• and
• calcining the metal oxide gel to form the metal oxide material;
• wherein the metal oxide material corresponds to the chemical formula of La2MxNi1-xO4, Pr2-yAyNiO4, or La2-zDzNiO4, wherein M is copper (Cu), cobalt (Co), iron (Fe), manganese (Mn), chromium (Cr), aluminum (Al), or platinum (Pt);
• A is lanthanum (La) or neodymium (Nd);
• D is calcium (Ca), barium (Ba) or strontium (Sr);
• x ranges from 0 to 1;
• y ranges from 0 to 2;
• and z ranges from 0 to 0.25.