Hydrogen cyanide sensor based on the porphyrin-like B4-doped [60]-fullerenes: a DFT study

Using density functional theory calculations, a porous C60 fullerene with B4 porphyrin-like cavity (C54B4) is designed, and its potential application is investigated in the HCN detection. The formation energy is predicted to be about − 155.5 kcal/mol, which is comparable with that of C54N4 nanocage (~ − 156.1 kcal/mol) and is somewhat less negative than that of [60] fullerene (~ − 161.0 kcal/mol). The C54B4 nanocage shows much higher electrical conductivity compared to the C60 and C54N4 nanocages. We found that the HCN adsorbs on the C54B4 nanocage via two different mechanisms, including vertical adsorption from its N-head and horizontal adsorption with N–C bond. These mechanisms differently affect the electronic properties of C54B4. The most stable HCN/C54B4 complex is that in which the HCN molecule lies on the center of B4 cavity so that each C or N atom is in connection with two B atoms with adsorption energy of about − 73.5 kcal/mol. Upon the HCN adsorption, a large charge transfer about 0.33 e and a great gap opening about 1.56 eV occurred for C54B4, which sharply increases the electrical resistance of C54B4, but its effect on work function is negligible. Thus, we concluded that C54B4 may be a promising electronic sensor for the HCN gas.