Quantum Dots Fight Water Pollution

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Chemical waste frequently ends up in water bodies, causing increasingly serious problems, as the chemicals are difficult to remove and the water becomes unusable. Quantum dots are here to change that.

Quantum dots are semiconductor-based crystals sized only a few nanometers that are capable of emitting light (usually deployed in electrical displays and solar cells). While most conventional quantum dots are derived from heavy metals and are therefore toxic, researchers from Aligarh Muslim University in India are working on nonmetallic environmentally friendly quantum dots that can be used in biological applications.

According to Interesting Engineering, the researchers have been developing Cdots and Sdots (quantum dots based on carbon and sulfur, respectively) for environmental applications, from creating safer invisible inks to decontaminating water supplies.

The tiny dots can detect and break down contaminants found in water sources, including pollutants like lead, cobalt, and chromium. This environmentally friendly method also prevents additional leaching of new metals from the dots.

Cdots, in addition to detecting pollutants, have shown the potential to break down water-based pollutants (like pesticides and dyes) and can be developed to soak up automobile oil. The researchers also reportedly intend to create a customized Cdot-based filtration system to assist in the event of an oil spill.

Furthermore, the team reportedly means to use this revolutionary invention in real-world and close-to-home scenarios, such as the Yamuna River in New Delhi (which is heavily polluted), in order to combat pollution at its source. The nonmetallic quantum dots can be used to detect and distinguish many different contaminants in the river, such as pesticides, surfactants, metal ions, antibiotics, and dyes.

The authors of the study explained in a press release: “Ideally, the dots will be functionalized to grab as many of these different contaminants on their surfaces as possible, so they can then be easily removed.”