Polarization induced dynamic photoluminescence in carbon quantum dot-based ionic fluid

Abstract

We have recently reported the synthesis of water-dispersible, polymer-passivated and redox-active carbon quantum dots (CQDs).

Stable Semiconducting Ink Based on a Polypyrrole/Carbon‐Quantum‐Dot Aqueous Colloidal Suspension: A Potential Sensor for Volatile Organics Present in Food

“…The acidic pH may be due to presence of few unbound SO 3 − H + groups as shown in Scheme .The presence of iron on CQD−Fesurface was confirmed from EDX data during TEM analysis (Figure SI1). DLS data of CQD−Fe shows increased hydrodynamic diameter (H d ) compared to earlier reported PSS‐CQDs (Figure a) . The increase in H d may be attributed to the formation of CQD−Fe colloidal clusters during impregnation of Fe 3+ ions through sharing of ligand sites available on multiple CQDs as shown in Scheme .…”

“…Aqueous PSS‐CQD suspension behaved as electrolyte without addition of supporting ions and exhibited stable redox behavior within a voltage regime of 3 V. Distinguishable oxidation and reduction peaks were noticed at +1.0 V and ‐ 0.52 V respectively . Owing to the presence of SO 3 − Na + groups, the powdery PSS‐CQDs were converted to a stable solvent‐less liquid through simple ion exchange process . The process involved resin based transformation of SO 3 − Na + to SO 3 − H + followed by acid‐base titration with a polyetheramine.…”

“…The process involved resin based transformation of SO 3 − Na + to SO 3 − H + followed by acid‐base titration with a polyetheramine. The titration resulted in the exchange of the surface H + ions with ammonium moieties of the polyetheramine and with the formation of stable solvent‐less ionic liquid‐like CQDs . The liquid‐CQDs too behaved as electrolyte in the voltage regime of 6 V. The aim of the present work is to improve the electronic properties of PSS‐CQDs by incorporating polypyrrole (PPy) on the CQD surface; thereby stabilizing the PPy‐coated CQD (CQD‐PPy) colloidal particles as a water‐based stable writable semiconducting ink.…”

“…At the very initial stage of synthesis, surface SO 3 − Na + groups of PSS‐CQDs were converted to SO 3 − H + by resin‐based ion exchange method in water . pH of the protonated PSS‐CQD suspension was found to be 2.5.…”

A Liquid Derivative of Phosphotungstic Acid as Catalyst for Benzyl Alcohol Oxidation in Water: Facile Separation and Stability of Benzaldehyde at Room Temperature†

“…Bhattacharjee et al . reported the preparation of nano ionic materials where Jeffamine ® was used as base or counter‐ion . The liquid nature of the dried PTA‐ Jeffamine ® catalyst is due to the low glass transition temperature of the polymer (T g =− 55°C) .…”