Doped Effects On The Electronic Properties Of Phosphorene Nanoribbons

Phosphorene,a novel two-dimensional(2D)material has been successfully fabricated in experiment in 2014 and attracted extensive research's interest due to the exotic properties and potential application in nanoelectronic devices.In practice,the performance and properties of phosphorene based devices are strongly influenced by the edge and doping.The nanoribbon is an effective model to simulate the edge and doping effect in 2D materials.However,it's lack of systematic studies of edge configurations and doping properties in phosphorene nanoribbons.Therefore,we have studied the structural,electronic and magnetic properties of phosphorene nanoribbons with different doping groups.(1)We perform first-principles calculation to study cooperation between the neighbor groups on the edge morphology and electronic properties of ZPNRs terminated by common groups H,F,O,S and OH.We find that the cooperation has little effects on the H(F)-terminated ZPNRs,but induces an edge reconstruction for the O(S)-terminated ZPNRs.The edge reconstruction derives from the repulsion between neighbor O atoms and the deformation of the P skeleton induced by the p state coupling between the edge,second edge and third edge P atoms.O-terminated ZPNRs is a semiconductor and enlarges the band gap,but induces an extra transport channel near the CBM and decreases the electronic effective mass in comparison with H-terminated ZPNRs.OH-terminated ZPNRs undergoes a doubling of the UC along the periodic direction because of the different directions of the neighbor O-H bonds at the same edge.In comparison with H-terminated ZPNRs,OH-terminated ZPNRs shows the similar band gap and electronic effective masses,but increases the effective mass of hole.(2)We perform first-principles calculation to study the size effects and the edge effects on the local magnetic moment of ZPNRs doped by the transition metals(including Fe,Co,Ni).It is found that the stable doping sites are all in the interior of the ribbons.The doping sites become insensitive to the edge when the distance is larger than 3 zigzag chains between the doping site and the edge.The Co dopant doesn't induce nonzero magnetic moment,while Fe and Ni dopants induce 1?B magnetic moment.The applied axial strain cannot modulate the magnetic moment for Fe,Ni and Co doped ZPNRs in the range from-8% to 12%.The local magnetic moments all result from the d orbital hybridization of the transition metal atoms.