A DFT study on the structural and electronic properties of Td and C2 symmetry C24X4 and C22X6 heterofullerenes (XÂ =Â B, Al, N, and P)

► Doping of four and six B, Al, N, and P on C28 leads to Td and C2 symmetry heterofullerenes.► Aromatic C24N4 and C22N6 are the most stable heterofullerenes among all. ► Electronic conductivity is increased through B and Al doping.