Experimental and computational investigation of highly selective dual-channel chemosensor for Al(III) and Zn(II) ions: construction of logic gates

Abstract

Abstract: The N,N ′-Bis(salicylidene)-2-hydroxy-phenylmethanediamine (BSHPMD) was synthesized and characterized by IR, UV-Vis and 1H NMR spectroscopic techniques. The single crystal X-ray diffraction studies reveal that the compound had a monoclinic crystal system with C2/c space group. The cation recognizing profile of the receptor BSHPMD was explored by UV-Vis and fluorescence spectroscopic methods. The receptor was found to recognize selectively Al 3 + and Zn 2 + ions over a panel of other metal ions such as Na +, Mg 2 +, Ca 2 +, Mn 2 +, Co 2 +, Ni 2 +, Cu 2 +, Sr 2 +, Cd 2 +, Ba 2 +, Hg 2 +and Pb 2 +. The Job’s plot analysis reveals that BSHPMD binds with Al 3 + and Zn 2 + in 1:1 stoichiometry ratio. The binding constants of the receptor for Al 3 + and Zn 2 + were 2.13 × 10 3 and 16.23 × 10 3M - 1, respectively. The detection limit for Al 3 + and Zn 2 + is 10.04 × 10 - 8 and 4.98×10-8M, respectively. The NMR titration and IR titration studies reveal the sensing mechanism of BSHPMD. The multi-ion detection of BSHPMD is used to construct NAND and OR molecular logic gates. Hirshfeld surface analysis based on DFT method with 3-21G as basis set is used to calculate various intermolecular interactions. Fingerprint plots are made to find out the percentage of different types of interactions. Graphical Abstract: SYNOPSIS We synthesized salicylaldehyde-based Schiff base sensor by facile condensation of easily available and inexpensive chemicals. The structure was established by single-crystal XRD study, Hirshfeld surfaces and fingerprint analysis. The compound can be used as a sensor for detecting Al 3 + and Zn 2 + ions selectively. The Schiff base sensor was found to be active even in the presence of many other metal ions. Intramolecular interactions existing in the Schiff base were calculated by DFT method. The multi-ion detection was used to construct NAND and OR Molecular logic gates. [Figure not available: see fulltext.].