Method for producing cobalt ferrite particles and cobalt ferrite particles produced by same

A method for producing cobalt ferrite particles, comprising:

• performing a thermal treatment on a ferrite precursor formed of a ferrous salt and a cobalt salt in the presence of a sulfite, wherein the thermal treatment is
• performed in a pressure vessel within a temperature range of 100° C. or higher and 190° C. or lower under a hydrothermal condition, and the resulting cobalt ferrite particles have an average particle diameter of 0.5 to 2 μm, or
• performed by heating the ferrite precursor at normal pressure within a temperature range of 60° C. or higher and lower than 100° C., and the resulting cobalt ferrite particles have an average particle diameter of 2 to 5 μm;
• wherein the cobalt ferrite particles have non-hollow spherical shapes;
• and
• wherein the cobalt ferrite particles have a CV value of 0.3 to 0.7.