Abstract: The present disclosure provides binder compositions formed with a plurality of binder materials having differing mean particles, the binder compositions being useful to improve washcoat adhesion on a substrate. Adhesion can be improved related to an increase in the binder concentration without a significant or substantial increase in associated viscosity. Such binder compositions can comprise a first binder material formed of a plurality of particles having a first mean particle size and a second binder material formed of a plurality of particles having a second mean particle size, wherein a ratio of the first mean particle size to the second mean particle size about 2 or greater. The present disclosure further provides catalyst compositions, catalyst articles, and emission systems incorporating the binder compositions.