title: Understanding the Photoluminescence Mechanism of Nitrogen-Doped Carbon Dots by Selective Interaction with Copper Ions.
abstract: Doped fluorescent carbon dots (CDs) have drawn widespread attention because of their diverse applications and attractive properties. The present report focusses on the origin of photoluminescence in nitrogen-doped CDs (NCDs), which is unraveled by the interaction with Cu(2+) ions. Detailed spectroscopic and microscopic studies reveal that the broad steady-state photoluminescence emission of the NCDs originates from the direct recombination of excitons (high energy) and the involvement of defect states (low energy). In addition, highly selective detection of Cu(2+) is achieved, with a detection limit of 10 μm and a dynamic range of 10 μm-0.4 mm. The feasibility of the present sensor for the detection of Cu(2+) in real water samples is also presented.
authors.affiliation: Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695 547, India.
authors.forename: Manjunatha
authors.initials: M
authors.lastname: Ganiga
authors.affiliation: Department of Chemistry, Indian Institute of Space Science and Technology, Thiruvananthapuram, 695 547, India. jobincyriac@iist.ac.in.
authors.forename: Jobin
authors.initials: J
authors.lastname: Cyriac
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002413:Cations, Divalent / Q000032:analysis; D003300:Copper / Q000032:analysis*; D057230:Limit of Detection; D049408:Luminescent Agents / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods; D009584:Nitrogen / Q000737:chemistry*; D045663:Quantum Dots / Q000737:chemistry*; D014867:Water / Q000032:analysis
chemical_list: D002413:Cations, Divalent; D049408:Luminescent Agents; D014867:Water; D002244:Carbon; D003300:Copper; D009584:Nitrogen
keywords: carbon nanodots; copper; nitrogen; photoluminescence; sensors