To find a suitable sensitivity sensor for dimethyl methylphosphonate (DMMP) as nerve agent, we studied the adsorption behavior of DMMP on the exterior surface of defected semiconducting (10,0) single-wall carbon nanotube (SWCNT) by means of first-principles van der Waals density functional (vdW-DF) calculations. The obtained results of adsorption energies reveal that the defect embedded within the (10,0) SWCNT does not promote binding capability in this system. Notably, analyzing the electronic structures and Mulliken population for the energetically most favorable complex supports that the defect changes slightly the electronic properties of SWCNT, indicating there is no considerable hybridization between the corresponding orbitals and the weak interaction obtained quantitatively in terms of binding energies. (C) 2012 Elsevier B.V. All rights reserved.