Abstract: A sensing device includes a robotic hand, an electrode and a triboelectric sensing layer. The robotic hand includes at least one robot finger. One robot finger is integrated with an electrode layer which is functionalized with a triboelectric sensing layer. The triboelectric sensing layer is composed of plurality of nanostructures including Tellurium. The robot hand with triboelectric sensing layer undergoes contact and separation with the target analyte solution having mercury ions which leads to the formation of mercury telluride owing to the highly selective between of mercury ions to the Tellurium surface. After contacting with the target analyte, the electron transfer ability of the nanostructures attached to robot finger is altered. This process of contact electrification causes the induction of electrons to the electrode layer generating the triboelectric output voltage. The triboelectric output voltage is utilized to determine the concentration of mercury ions in the target analyte solution.