Multiresponsive luminescent probe for Fe³⁺, CrO₄^2- and Cr₂O₇^2- in aqueous solution based on N,N’-bis-pyridin-2-ylmethylene-hydrazine and phthalate ligands

Abstract

One new luminescent metal-organic framework (LMOF), {[Cd₂(L) (BDC)₂(H₂O)₂]·4H₂O}_n (1) (L = N,N’-bis-pyridin-2-ylmethylene-hydrazine, H₂BDC = phthalic acid), was synthesized and structurally characterized by single-crystal X-ray diffraction analysis, elemental analysis, infrared spectroscopy and thermogravimetric analysis. Complex 1 exhibits two-dimensional (6,3)-topological layer structures that are further stabilized by hydrogen bonds into a 3 D architecture. Luminescence experiments showed that 1 can act as a turn-off luminescent probe for the sensitive and selective detection of Fe³⁺, CrO₄^2-, and Cr₂O₇^2- ions. The detection limits as well as the possible quenching mechanism was also explored.

Graphical Abstract

Keywords:

• Luminescent metal-organic frameworks
• crystal structure
• selective sensing
• fluorescence quenching

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the Provincial Natural Science Foundation of Anhui (Nos. 1408085QB32 and 2008085QB55), the Key Project of Anhui Provincial Fund of Distinguished Young Scholars in Colleges and Universities (No. 2013SQRL059ZD), the Program for Innovative Research Team in Anqing Normal University, Anhui Provincial Teaching Demonstration Course (No. 1498), Quality Engineering Project of Anqing Normal University (No. 2020aqnujyxm14) and the Open Project of Anhui Key Laboratory of Optoelectronic and Magnetic Functional Materials (ZD2020005).