Adsorbate induced modulation of strain effects on work functions of a tungsten (100) surface.

The effects of strain on the work functions of tungsten surfaces covered with a monolayer of adsorbates have been studied systematically using ab initio density functional theory. It has been found that the strain on tungsten surfaces due to different atomic coverages exhibits very interesting influences on the surface work function. For a clean tungsten surface, a compressive strain more profoundly increases the work function than a tensile strain, and the strain dependence of the work function shows a concave trend.

Strain and screening effects on field emission properties of armchair graphene nanoribbon arrays: a first-principles study.

The field screening effect on the field-emission properties of armchair graphene nanoribbons (AGNRs) under strain has been studied using first-principles calculations with local density approximation (LDA). Using the zone folding method with the effect of a dipole barrier along with the work function of strained graphene, we can obtain the work function of AGNR of any width under strain, confirmed with the LDA calculations. We have systematically investigated the effects of inter-ribbon distance and ribbon width on the work function of AGNR arrays.

Screening effects on the field enhancement factor of zigzag graphene nanoribbon arrays: a first-principles study.

The field screening effect on the electronic and field-emission properties of zigzag graphene nanoribbons (ZGNRs) has been studied using first-principles calculations. We have systematically investigated the effects of inter-ribbon distance and ribbon width on the work function, field enhancement factor, band gap and edge magnetism of zigzag graphene nanoribbons (ZGNRs). It is found that the work function of ZGNRs increases rapidly as the inter-ribbon distance Dx increases, which is caused by the positive dipole at the edge of the ribbon.