An intramolecular charge transfer (ICT) based chemosensor for silver ion using 4-methoxy-N-((thiophen-2-yl)methyl)benzenamine

Abstract

4-Methoxy-N-((thiophen-2-yl)methyl)benzenamine was found to be a highly selective chemosensor for Ag⁺ ion in methanol–water (1 : 1 v/v) mixture over other metal ions such as Na⁺, K⁺, Li⁺, Cu⁺, Ba²⁺, Cd²⁺, Co²⁺, Cu²⁺, Fe²⁺, Hg²⁺, Mn²⁺, Ni²⁺, Pb²⁺ and Zn²⁺ with a limit of detection (LOD) is 5.0 × 10⁻⁶ mol L⁻¹. Upon binding to Ag⁺ ion, a strong fluorescent enhancement is observed which is attributed to an increase in intramolecular charge transfer (ICT). The proposed mechanism is strongly supported by TD-DFT calculations.