In recent years, the integration of nanostructure assemblies has led to unprecedented levels of control over the fabrication and functional properties of materials, with numerous potential applications. Here, we highlight the recent contributions towards the fabrication of multi-layered assemblies of carbon nanotubes (CNTs) decorated with gold nanoparticles (Au NPs) on porous materials. In this study, a three-component composite consisting of functionalized carbon nanotubes (CNTs), anodized aluminium oxide (AAO), and Au NPs was designed and synthesized in the form of a free-standing catalyst using a simple and unsophisticated technique for the first time. The AAO were coated with carbon nanotubes and gold nanoparticles and used as the supports for the catalytic. The CNTs-AAO composite was prepared by spin-coating of CNTs on the AAO surface. The Au NP layers were incorporated into the CNTs-AAO composite by immersing the composite in a gold solution. The Au-CNTs-AAO assemblies were tested for catalytic performance in the reduction of p-nitrophenol (p-NP) to p-aminophenol (p-AP). The Au-CNTs-AAO exhibited superior catalytic activity, with a reaction rate (k) of 0.678 min −1, higher than those of Au-CNTs and Au-AAO. Additionally, the Au-CNTs-AAO assemblies prepared with support of different AAO porosities showed that the catalytic activity increased as the pore diameter increased from 40 to 80 nm. Subsequently, it was demonstrated that the surface functionalization of CNTs with the silane moiety leads to higher catalytic activity compared to unfunctionalized CNTs. This efficient approach to the design and construction of this porous support improved the catalyst's properties in the reduction of p-NP, such as the catalytic performance, thermal stability, natural separation and reusability. These layered assemblies can potentially serve as a platform for various catalytic activities.