Carbon-quantum dots derived from denatured milk for efficient chromium-ion sensing and supercapacitor applications

Abstract We demonstrate here a sustainable approach to generate carbon-quantum dot (CQD) using denatured (spoiled) milk by a simple one-step hydrothermal method. The unique photophysical property of the CQD has resulted in selective sensing of the chromium ions (Cr6+) as low as 14 µM in control and environmental water samples. The CQD electrode delivered a specific capacitance of 95 F g−1 with an exceptional stability over 1000 cycles.