Castor seed-derived luminescent carbon nanoparticles for metal ion detection and temperature sensing applications
Avinash Kumar, Ishant Kumar, Sandeep Kumar, Ankita Sharma, Arvind K. Gathania
Abstract
Abstract In the current study, castor seeds are used as a first-time natural precursor in the hydrothermal process of making carbon nanoparticles. The produced nanoparticles have a non-uniform size distribution with an average diameter of 13 nm and a roughly spherical shape. They comprise a variety of functional groups containing carbon, nitrogen, and oxygen. Their spectra have peaks at 524 nm and 441 nm for their emission and excitation, respectively. They exhibit temperature-sensitive Photoluminescence (PL) behaviour, high quantum yield value (24%), and excitation-dependent emission. In high salt environments, UV radiation, storage time, and fluorescent light they provide exceptional photostability. They have been used in applications for metal ion and thermal sensing. With a limit of detection (LOD) value of 18 μ M, they are found to be both sensitive and selective to Fe 3+ ions. Additionally, a nanothermosensor with good recovery and a broad temperature range (5 °C–85 °C) has also been demonstrated with a thermal sensitivity of 0.54% °C −1 based on their temperature-sensitive behaviour.