Efficient fuel combustion catalyst delivery device and method are provided. A fuel combustion catalyst delivery device includes a storage vessel that contains a liquid. The liquid includes one or more catalytic materials. The storage vessel is attached to a nebulizer that can convert the liquid to an aerosol to be delivered into an air intake of a combustion zone. The aerosol can accelerate fuel combustion. The storage vessel and the nebulizer are made from materials suitable to be exposed to the liquid and the aerosol. The storage vessel and the nebulizer are also suitable to be placed in proximity to the combustion zone such as an engine compartment so that the aerosol can be delivered into the air intake of the combustion zone easily and effectively. The surfaces of the delivery device exposed to the liquid or the aerosol may be made of corrosion-resistant or inert materials if the liquid is acidic. The surfaces of the delivery device exposed to the liquid or the aerosol may be also made from materials that produce substantially no contaminants into the liquid. The nebulizer may convert the liquid to an aerosol at a rate between once per second and one hundred times per second. The nebulizer may have holes for passing the liquid where each of the holes has a size not greater than about 10 .mu.m. The delivery device can deliver up to 500 ml or more of liquid as aerosol over 500 hours of operation.