Solid membranes for degradation of emerging contaminants such as atrazine is of significant interest for water engineering applications. In this study, nanocatalyst particles have been anchored on vertically-aligned carpet-like arrays of carbon nanotubes (CNT) grown on porous carbon foams. This hierarchical architecture combines the advantages of highly surface-active nanoparticles with the robust and reusable structural advantage of porous solid membranes suitable for water treatment devices. Three types of palladium-based nano-catalytic surfaces have been investigated: metallic palladium (Pd), Pd nanoparticle with a layer of oxide (PdO-coated Pd), and Pd nanoparticle coated with thin film of silver (Ag-Pd). Their catalytic activities have been compared by analysing the degradation rate of atrazine in water. It is noted that all three catalysts show high levels of atrazine degradation, with the PdO-coated nanoparticles showing the highest kinetics. These results demonstrate that hierarchical hybrid architectures can provide compact and powerful surface-active materials such as adsorbents and catalytic degradation devices in future water treatment applications.