▎ 摘　　要

Twin T-graphene is a new three atomic layer thick two-dimensional carbon allotrope. In the current research, the structural and electronic properties of 3d transition metal (TM) embedded twin T-graphene are studied utilizing density functional theory (DFT) calculations. All 3d TM atoms transfer charge to the neighboring C atoms, and strongly get adsorbed to the sheet. Our findings reveal that the electronic properties of twin T-graphene are modulated by TM adsorption. The twin T-graphene is a semiconductor, while TM decorated twin T-graphene shows different electronic properties depending on the species and concentration of TM atoms. The semiconductor for Sc, Ti, V, Cr, and Zn adsorption, metal for Mn, Cu, and Ni adsorption, and bipolar magnetic semiconductor for Fe and Co adsorption are observed. The energy band gap of TM embedded twin T-graphene sheets with semiconducting properties decreases with increasing the concentration of TM atoms. Our results indicate that TM embedded twin T-graphene can be used in electronic and spintronic devices.