Ultra-thin two-dimensional nanosheets for in-situ NIR light-triggered fluorescence enhancement

Abstract

Ultra-thin two-dimensional (2D) nanosheets of Zn-based metal -organic framework (MOF) were prepared from the precursor [Zn(bpydc) (H2O)·H2O]n (bpydc = 2,2′-bipyridine-5,5′-dicarboxylate), by using a liquid phase ultrasonic stripping technique. The atomic thickness and the abundant oxygen atoms making the nanosheets are well dispersed in various solvents, exhibiting unique fluorescence responses to solvents of different polarities. Adding on, by loading on the ytterbium ion (Yb3+)-sensitized hexagonal phase up-converting nanoparticles (UCNPs, sodium yttrium fluoride (NaYF4): 20 mol% Yb3+, 1 mol% erbium (Er3+ ions)) on the surfaces of nanosheets, the in-situ near infrared (NIR) light (980 nm) triggered luminescence enhancement has been observed, suggesting the favorable application foreground in biomedical science, super-capacitors, and electronic devices.