Enhanced sensing of organometallics on defect-engineered chalcogenide systems

Chalcogenide systems often exhibit intrinsic defects during fabrication due to technological limitations. In this work, we investigated the effects of single-atom (metal or chalcogen) vacancies and metal-chalcogen divacancies in group IV monochalcogenides on the sensing of organometallic molecules. We observe that defective chalcogenides with low formation energies enhance molecular adsorption while maintaining reasonable recovery times. The interaction strength follows the hierarchy: metal-vacancy > divacancy > chalcogen-vacancy, contrasting with the substrate stability order: metal-vacancy > chalcogen-vacancy > divacancy. Organometallic molecules preferentially adsorb parallel to the surface plane at an angle rather than vertically. Analysis of the electronic structure revealed an n-type sensing mechanism for cobaltocene adsorption, with half-metallic and bipolar magnetic semiconducting properties.