Synthesis of amphiphilic carbon quantum dots with phosphorescence properties and their multifunctional applications

Abstract

Amphiphilic quantum dots with phosphorescence properties have been synthesized and applied for ion detection and two-photon cell imaging.

Carbon Dots‐in‐Matrix Boosting Intriguing Luminescence Properties and Applications

“…The PVA is found to be an ideal candidate for preparing composite film. CDs@PVA composite film can be easily fabricated by homogeneous dispersion of as‐prepared CDs into a PVA aqueous solution, followed by coating and drying/annealing . Such a method is very simple, in contrast to the abovementioned chemical methods for CDs‐based composites.…”

“…The CDs dispersed in water or in PVA film showed emissions at 400 nm when excited under 325 nm, but the CDs in a PVA matrix displayed an extra phosphorescence at 500 nm with a lifetime of 350 ms after UV light was turned off ( Figure a–c). Later, two RTP composites with lifetimes of 450 and 8.7 ms were prepared by doping CDs and CDs in PVA and PU matrices, respectively . More recently, thermal‐treatment controlled RTP composites were discovered in which the green phosphorescence appeared in different CDs@PVA films after different thermal annealings (150 or 200 °C) .…”

Facile, Quick, and Gram‐Scale Synthesis of Ultralong‐Lifetime Room‐Temperature‐Phosphorescent Carbon Dots by Microwave Irradiation

“…[15,19,34] According to these considerations,w ehave found ao nepot method for the facile and quick preparation of ultralong RTP( URTP) CDs.A ss hown in Figure 1a,b,g ram-scale URTP CDs can be obtained in afew minutes via microwaveassisted heating of an ethanolamine and phosphoric acid aqueous solution, and subsequent dialysis purification and freeze-drying (more details in Supporting Information). [26][27][28][29][30][31][32] Note that the as-developed method features facile,quick and scalable merits,t he obtained product possesses URTP life-time and could potentially be employed as security ink in anti-counterfeiting and information protection. Importantly,t he CDs present the longest RTPlifetime to be 1.46 s(more than 10 s to naked eye,F igure 1c and Video 1i nS upporting Information) among the reported CDs-based materials to date.…”

Carbon Dots with Dual‐Emissive, Robust, and Aggregation‐Induced Room‐Temperature Phosphorescence Characteristics

“…[26,47] Thec haracteristic absorption peaks located at 1689, 1280, 1421, and 937 cm À1 originate from the stretching vibrations of C=Oa nd CÀOb onds,a nd the in-plane and out-of-plane bending vibration of ÀOH on aromatic carboxyl groups (ÀCOOH), respectively. [26,[47][48][49] These FTIR results can be further confirmed by the XPS analysis.Asshown in Figure 2f, the TA-CDs mainly contain Ca nd Oe lements with corresponding contents to be 63.32 %a nd 36.68 %, respectively. TheH RX PS C1ss pectrum can be deconvoluted into four peaks at 284.6, 285.6, 288.8, and 290.5 eV (Figure 2g), contributing to C=Ca nd CÀOb onds, ÀCOOH group,a nd p!p*s hake-up of aromatic network, respectively.…”

“…[48][49][50] The HR XPS O1ss pectrum is fitted by two peaks at 531.8 and 533 eV that can be assigned to O=Ca nd CÀOb onds, respectively ( Figure 2h). [26,47,48] Moreover,t he 1 Ha nd 13 CNMR spectra exhibit that the TA-CDs only contain aromatic H(7.62-8.48 ppm) and carboxyl H(13.28 ppm), and sp 2 C( 129.58-134.89 ppm) and carboxyl C( 167.12 and 167.05 ppm), respectively (Supporting Information, Figures S1 and S2). [51,52] To further clarify the formation and chemical structure of TA-CDs,F TIR and NMR spectra of the precursor TA were also measured and compared with that of the TA-CDs.I n detail, the obviously reduced absorption at 3427 cm À1 ( À OH stretching vibration from carboxyl groups) and increased absorptions at 1610, 1578, 1510, and 1421 cm À1 (C=Cstretching vibrations) in FTIR spectra from TA to TA-CDs imply the loss of carboxyl groups and production of more sp 2 structures in the TA-CDs (Figure 2e).…”