LAUSR

Experimental works have exposed that Al-doping in the structure of ZnO nanostructures intensely increases their electronic sensitivity toward various chemicals. Herein, density functional theory calculations were employed to inspect the Al-doping effect on the sensitivity of a ZnO nanosheet (ZnOS) to the isoniazid (IS) drug. The pristine ZnOS physically adsorbs an IS molecule with adsorption energy (E ad) of −6.8 kcal/mol, and the sensing response value of 2.3 at 298 K. Replacing a Zn atom by an Al atom strengthens the interaction, increasing the E ad to −20.8 kcal/mol. Also, the Al-doping significantly increases the sensing response value to 150.3 by rising the electrical conductivity of the sheet. A short recovery time of 11.3 s is predicted for the Al-ZnOS-based sensor. The water solvent somewhat strengthens the interaction of IS drug with the Al-ZnOS, increasing the sensing response from 150.3 to 175.8. We concluded that the Al-doping makes the ZnOS a promising sensor for IS drug detection. GRAPHICAL ABSTRACT