The air pollution reduction is crucial for health and environmental reasons. Many efforts have already being done for the adsorption of air pollutants (e.g. CO2 molecule) on various substrates. Ti nanostructures on carbon substrates have attracted a lot of attention because of their potential applications in electronic nanodevices, molecular adsorption and gas sensors. Moreover, excellent functionalities (e.g. molecular adsorption) were found for Ti nanostructures on carbon surfaces, depending on the size and the morphology.  We report on Density Functional Theory (DFT) results referring to TiN nanostructures (nanoclusters and nanowires) supported on carbon nanotubes and graphene along with the interaction with CO2 molecules for selective hybrids. Starting with Ti adatom we found that it‘s energetically favored adsorption sites depend on the diameter of zigzag (n,0) SWCNTs or graphene playing important role at the deposition of larger Ti 2D or 3D nanostructures. The nanowires‘ growth depends on the structural characteristics of SWCNTs while they may transforms the cylindrical SWNTs‘ shape to ellipsoid. Additionally, the Ti-NWs inside the SWNT appear to be more stable compared to the outside cases. Concerning the electronic properties of these hybridic systems, it was found that Ti atoms introduce new energy states at the Fermi level, transforming the semiconductor (8,0) and (10,0) SWCNTs as well as graphene to conductors. Most of the new electronic states are characterized by strong Ti3d-C2p hybridizations, while in all studied systems identified significant charge transfer from the Ti adsorbates towards to the carbon substrates. The interaction between the smaller Ti nanostructures (Ti, Ti2, Ti3, Ti7 and Ti13) and the carbon substrates results in the formation of active sites for additional atomic or molecular adsorption, while the Ti-NWs/SWCNTs hybrid systems are characterized by continue electronic areas along the tubes‘ axis. These results were compared with Cu nanostructures on SWNTs and graphene which did not provide interesting active sites or dangling bonds.  The chosen hybridic systems for further CO2 molecule adsorption was the TN/Graphene, with N = 1,3,13. At Ti/Graphene system, the adopted CO2 molecule prefers to reduce into CO and O, while only one Ti atom can bind up to three CO2. The Ti3/Graphene is the only hybridic system in which the adsorbed molecules are not reduced, while at the Ti13/Graphene the reduction of CO2 into CO and O followed by the Ti-NC deformation. These TiN/Graphene hybrid systems are capable to adsorb CO2, and the bigger is the Ti-NC structure the stronger is the molecule adsorption. Through the sequential CO2 addition, we received CO2 adsorption paths on the TiN/Graphene systems. These paths depend on molecule deposition site, the configuration of already adsorbed CO2 and the substrate structure. Although the CO2 contribution is localized at low energies, however its interaction with the substrate affects on the states at the Fermi level. The charge accumulation as well as the dangling bonds, which are mainly located at the Ti atoms, indicates the sites where an additional molecule may adsorbed. Finally, it was found that charge transferred from the Ti nanostructures to grapheme and especially to the adsorbed CO2 molecules. These findings enlighten the early stages of CO2 adsorption on TiN/graphene and may be of use for catalysis applications.