Regulating the rectifying effect of zigzag germanium selenide nanoribbons by selective edge decoration.

Germanium selenide (GeSe) nanoribbons as quasi-one-dimensional materials are expected to host fascinating tunable electronic properties due to the edge state and quantum confinement effect. Herein, the effect on the electronic structures and transport properties of zigzag GeSe nanoribbon (ZGeSeNR) of different functional passivation groups is systematically studied using a combination of density functional theory and the non-equilibrium Green's function. The N-, P-, and S-passivated ZGeSeNRs are metallic, while the F-, Cl-, OH-, and H-passivated ones exhibit semiconductor properties. The rectification behavior is found in lateral ZGeSeNR heterojunctions composed of a metal–semiconductor contact, and the rectification performance can be modulated by changing the edge passivation group, the ribbon width, and the length of the scattering region. Especially, the highest rectification ratio (RR) reaches 9.2 × 106 in the S–H–ZGeSeNR heterojunctions, in which the left and right half-edge atoms are passivated by the S and H groups, respectively. These results are useful for the design of nanoscale rectifiers based on ZGeSeNRs. [ABSTRACT FROM AUTHOR]