Tuning the functional groups of carbon quantum dots in thin film nanocomposite membranes for nanofiltration

2018 ◽  
Vol 564 ◽  
pp. 394-403 ◽  
Author(s):  
Huazhen Sun ◽  
Peiyi Wu
Keyword(s):  
Thin Film ◽  
Quantum Dots ◽  
Functional Groups ◽  
Carbon Quantum Dots ◽  
Nanocomposite Membranes ◽  
Thin Film Nanocomposite

Forward osmosis application of modified TiO2-polyamide thin film nanocomposite membranes

2015 ◽  
Vol 57 (30) ◽  
pp. 14013-14023 ◽  
Author(s):  
Maryam Amini ◽  
Ahmad Rahimpour ◽  
Mohsen Jahanshahi
Keyword(s):  
Thin Film ◽  
Forward Osmosis ◽  
Nanocomposite Membranes ◽  
Thin Film Nanocomposite

Novel thin film nanocomposite membranes incorporated with functionalized TiO2 nanoparticles for organic solvent nanofiltration

2014 ◽  
Vol 241 ◽  
pp. 155-166 ◽  
Author(s):  
Majid Peyravi ◽  
Mohsen Jahanshahi ◽  
Ahmad Rahimpour ◽  
Ali Javadi ◽  
Saeideh Hajavi
Keyword(s):  
Thin Film ◽  
Organic Solvent ◽  
Tio2 Nanoparticles ◽  
Nanocomposite Membranes ◽  
Organic Solvent Nanofiltration ◽  
Thin Film Nanocomposite

scholarly journals Synthesis and Properties of Nitrogen-Doped Carbon Quantum Dots Using Lactic Acid as Carbon Source

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 466
Author(s):  
Kaixin Chang ◽  
Qianjin Zhu ◽  
Liyan Qi ◽  
Mingwei Guo ◽  
Woming Gao ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Lactic Acid ◽  
Fluorescence Quenching ◽  
Functional Groups ◽  
Fluorescence Intensity ◽  
Carbon Quantum Dots ◽  
Nitrogen Doped ◽  
Ph Values ◽  
Wide Range ◽  
Nitrogen Doped Carbon

Nitrogen-doped carbon quantum dots (N-CQDs) were synthesized in a one-step hydrothermal technique utilizing L-lactic acid as that of the source of carbon and ethylenediamine as that of the source of nitrogen, and were characterized using dynamic light scattering, X-ray photoelectron spectroscopy ultraviolet-visible spectrum, Fourier-transformed infrared spectrum, high-resolution transmission electron microscopy, and fluorescence spectrum. The generated N-CQDs have a spherical structure and overall diameters ranging from 1–4 nm, and their surface comprises specific functional groups such as amino, carboxyl, and hydroxyl, resulting in greater water solubility and fluorescence. The quantum yield of N-CQDs (being 46%) is significantly higher than that of the CQDs synthesized from other biomass in literatures. Its fluorescence intensity is dependent on the excitation wavelength, and N-CQDs release blue light at 365 nm under ultraviolet light. The pH values may impact the protonation of N-CQDs surface functional groups and lead to significant fluorescence quenching of N-CQDs. Therefore, the fluorescence intensity of N-CQDs is the highest at pH 7.0, but it decreases with pH as pH values being either more than or less than pH 7.0. The N-CQDs exhibit high sensitivity to Fe3+ ions, for Fe3+ ions would decrease the fluorescence intensity of N-CQDs by 99.6%, and the influence of Fe3+ ions on N-CQDs fluorescence quenching is slightly affected by other metal ions. Moreover, the fluorescence quenching efficiency of Fe3+ ions displays an obvious linear relationship to Fe3+ concentrations in a wide range of concentrations (up to 200 µM) and with a detection limit of 1.89 µM. Therefore, the generated N-CQDs may be utilized as a robust fluorescence sensor for detecting pH and Fe3+ ions.

Sign in / Sign up

Export Citation Format

Share Document