Highly Sensitive CO Gas Sensor from Defective Graphene: Role of van der Waals Interactions

Table 2

Comparison of the calculated adsorption energy ( in eV) and equilibrium molecule-substrate distance ( in Å) at sites h and l of graphene and defective graphene, respectively, between different vdW functionals.

Methods	h		l
	PBE + vdW	−0.11	2.88	−2.15	1.33
DFT-D2	−0.09	2.87	−2.25	1.33
DFT-D3	−0.10	2.92	−2.17	1.33
vdW-DF	−0.14	3.02	−1.80	1.33
optB88-vdW	−0.11	2.77	−2.04	1.33
optPBE-vdW	−0.16	2.93	−2.01	1.33