Methods for preparing ceria-zirconia (CZO) materials calcined with precious group metals (PGM) include calcining a CZO material with PGM. The calcined CZO/PGM catalyst is reduced at a temperature of ≥1000° C. to ≤1100° C. for a time of ≥0.5 hour to 1 hour to form a (CZO/PGM)-pyrochlore catalyst. The (CZO/PGM)-pyrochlore catalyst exhibits superior oxygen storage capacity characteristics as a three-way catalyst in vehicle exhaust gas systems.