氮氧添加对纳米固体功函数的调制

model is presented towards measures lowering the work function for high-efficiency electron emission. It is suggested that an oxide or nitride tetrahedron formation creates nonbonding lone pairs that induce the anti-bonding dipoles associated with density of states that added to a position above the Fermi level and that nano-fabrication could densitify the charges in the confined region due to the coordination number (CN)-imperfection-induced bond contraction. However, over dosing N or O may cause hydrogen-like bond formation with “dipole/+” valence state that could recovers the reduced work function. Closely packed nanotips also recover the work function to that of a flat surface. It is anticipated that the work function of a surface can be lowered by proper co-doping O or N with metals of low-work function to the miniaturized tips. Predictions agree with various experimental observations.