Titanium and copper tailoring of fullerene (Cu-Ti@C60) as a sensor nanostructured for toxic gas pollutants: A DFT study

Abstract

Here, a fullerene-based (C₆₀) material comprising sixty carbon atoms was selected due to its advantageous properties including sensitivity, electrical conductivity, and having a structure that can be readily modified. The C₆₀ bare surface was further doped with Ti, a metal, and then decorated with Cu to improve its overall properties and enhance its adsorption of NO₂, NO, CO₂, CO, and SO₂ gasses using the density function theory (DFT) computation conducted at the PBE0/LanL2DZ level of theory. The surface Cu-Ti@C₆₀ was studied at the O, N, and C sites to determine the sites exhibiting the highest adsorption strength for the studied gases. The NO₂-N-Cu-Ti@C₆₀ complex possessed the most significant adsorption energy of −14.3571 eV while the CO₂ binding at the O-site exhibited the lowest adsorption energy of −0.58638 eV. This indicates that the Cu-Ti@C₆₀ surface binds greatly to the NO₂ and NO gases with a good adsorption strength observed for SO₂ gas. Also, there was a minimal change in the energy gap of the surface after adsorption with studied gases which showcased the stability of the systems. These analyses carried out in this study position Cu-Ti@C₆₀ surface to be a promising material in developing a sensor device for NO₂, NO, CO₂, CO, and SO₂ with a strong adsorption rate for NO₂, NO, SO₂, CO, CO₂ in a descending sequence.