The present invention includes a catalyst structure and method of making the catalyst structure for Fischer-Tropsch synthesis that both rely upon the catalyst structure having a first porous structure with a first pore surface area and a first pore size of at least about 0.1 μm, preferably from about 10 μm to about 300 μm. A porous interfacial layer with a second pore surface area and a second pore size less than the first pore size is placed upon the first pore surface area. Finally, a Fischer-Tropsch catalyst selected from the group consisting of cobalt, ruthenium, iron and combinations thereof is placed upon the second pore surface area. Further improvement is achieved by using a microchannel reactor wherein the reaction chamber walls define a microchannel with the catalyst structure placed therein through which pass reactants. The walls may separate the reaction chamber from at least one cooling chamber. The present invention also includes a method of Fischer-Tropsch synthesis.