Localized Surface Plasmonic Resonance (LSPR) consists of collective oscillations of free electrons in noble material nanoparticles. This interesting phenomenon can be used in gas sensing applications due to variations of the refractive index of the surrounding environment and a strong local electric field. As a result, LSPR-based devices can be potentially suitable in the detection of small concentrations of different analytes. So far, several plasmonic structures have been implemented to improve both this capability of gas detection and a strong selectivity towards different analytes. Most of these aforementioned architectures are basically bilayered, but in this project a 3D metamaterial will be presented: thanks to an innovative sinthesis technique such as Double Spray Flame Pyrolysis (DSFP) one is able to fabricate a plasmonic resonant architecture in which plasmonic properties are exploited better than in bilayers and, consequently, enhanced performances are possible..