Multicolor CdSe quantum dots as gasoline nanomarkers

Abstract

The markers commonly used to detect fraud and adulteration in fuels are conventional organic molecules. Recent developments in nanotechnology have gained an important role in this field. The novelty of this work is the application of multicolor semiconductor fluorescent nanocrystals, CdSe quantum dots (QDs), as gasoline nanomarkers. QDs with fluorescence emissions ranging from green to red were evaluated as gasoline nanomarkers. They retained their colloidal and fluorescence stability after more than 5 years, as verified by visualization under UV light and by absorption and fluorescence spectra. Additionally, they were clearly detected in gasoline concentrations of around 40 ppm. Advantages of this class of nanomarkers over traditional organic molecules markers are: the simpler production process, the high photostability and the ease and sensitivity of detection based on fluorescence emission in multicolored wavelengths. Thus, the application is potentially useful for different gasoline matrices. For instance, CdSe quantum dots could be used to differentiate regular gasoline from gasoline with additives, or differentiate gasolines produced in different sources and thus subjected to different commercial taxation. Therefore, this study presents nanomaterials such as CdSe QDs and their optical properties, used as gasoline nanomarkers, as a technological innovation in the field of Chemical Engineering.

Graphical abstract