Development of ferromagnetism and formation energetics in 3d TM-doped SnO2: GGA and GGA + U calculations

•Formation energy strongly depends on the TM dopant size.•Cudoped SnO2 displays magnetic metallic behavior having 85.3% spinpolarization.•A halfmetallic ferromagnetism is obtained in Cudoped SnO2 within GGA + U.•3d TM orbitals are mainly responsible for the magnetism. Electronic and magnetic properties of several 3d transition metals (Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) doped SnO2 by means of ab initio calculations. First, we successfully reproduced the experimental band gap (3.60 eV) of bulk SnO2 within GGA + U scheme. Our results show that calculated formation energies of doped systems strongly depend on the dopants atomic numbers (Z). It is found that Ti-doped SnO2 structure exhibits non-magnetic insulating behavior, while V-, Cr-, Mn-, Fe-, and eeCo-doped systems illustrate magnetic semiconducting states within both (GGA and GGA + U) schemes. Ni-doped SnO2 holds non-magnetic/magnetic semiconducting nature for GGA/GGA + U methods. Surprisingly, Cu-doped SnO2 displays magnetic metallic behavior having 85.3% spin-polarization within GGA scheme, while like half-metallic character is obtained for GGA + U. Hence, the present work indicates that Cu-doping is an effective way to induced interesting magnetism in SnO2, which have potential applications in spintronics.