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Download fileMgO Nanocubes as Self-Calibrating Optical Probes for Efficient Ratiometric Detection of Picric Acid in the Solid State
journal contribution
posted on 12.09.2018, 00:00 authored by Subrata Senapati, Karuna Kar NandaFluorescence intensity ratio (FIR)-based
optical sensing where
ratio between the intensity of two different wavelength emissions
is considered for analyzing sensing performance have advantages over
the conventional single wavelength emission based sensing in various
aspects. Here, we have demonstrated the MgO nanocubes, synthesized
by simply heating Mg ribbons in air atmosphere, for possible self-calibrated
picric acid (PA)-sensing application by employing FIR-based technique
in solid state. The as-prepared MgO nanocubes at 600 and 1200 °C
show two emission peaks with both 355 and 532 nm excitation. The intensity
ratio between these two emissions is considered for PA sensing. With
an increase in the PA concentration, the PL intensity of both the
peaks decreases: One with a faster rate as compared to that of the
other one. Hence, the ratio is considered for sensing applications.
The decrease in the PL intensity is possibly due to a static quenching
process, following ground-state electron transfer from MgO to PA.
Interestingly, the nanocubes show high stability and longevity for
repeated washing cycles.