X8R type fine-grained ceramics capacitor dielectric material and preparation method thereof

The invention discloses an X8R type Ba[1-x]BixTiO3@(Nb2O5-Co3O4) fine-grained ceramic capacitor dielectric material and a preparation method thereof. The general formula of chemical composition of the X8R type fine-grained capacitor dielectric material meets Ba[1-x]BixTiO3+n(aNb2O5+bCo3O4), wherein x is more than 0.002 and less than and equal to 0.015, n is equal to 0.004 to 0.016, a is equal to 0.15 to 0.60mol%, and b is equal to 0.03 to 0.14mol%. The powder material prepared by adopting a precipitation method and a liquid phase coating method meets the indexes as follows: the powder separation of Ba[1-x]BixTiO3 is good, the grain size of the particle is controlled between 50 and 500 nm, and the thickness of the composite oxide coating layer is controlled between 5-30 nm; the performance of the prepared ceramic dielectric material reaches the indexes as follows: ceramic discs is sintered at a temperature range of 1100 to 1300 DEG C, the crystal grain of the ceramic is controlled between 100 and 550nm, the indoor temperature dielectric constant is less than 2600, the indoor temperature dielectric loss is less than 2.5%, and delta C/C25 DEG C is less than +/-15% between the temperature scope from -55 DEG C to 150 DEG C.