Optical properties and zeta potential of carbon quantum dots (CQDs) dispersed nematic liquid crystal 4′- heptyl-4-biphenylcarbonitrile (7CB)

Pandey, Fanindra Pati; Rastogi, Ayushi; Singh, Shri

doi:10.1016/j.optmat.2020.109849

Cited by 59 publications

(10 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Zeta potentials of N-CQDs and CQDs are −3.43 and 5.17 mV (Fig. S12 †), respectively, which indicates that both samples are prone to form dense packed films on the substrate, 44 promoting the π-π interaction. In other words, we obtained a modulation method to weaken the intrinsic PL quenching of solid-state film samples.…”

Section: Resultsmentioning

confidence: 99%

Electrochemical control of emission enhancement in solid-state nitrogen-doped carbon quantum dots

Huang

Zhang

et al. 2022

Nanoscale

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 99%

Electrochemical control of emission enhancement in solid-state nitrogen-doped carbon quantum dots

Huang

Zhang

et al. 2022

Nanoscale

View full text Add to dashboard Cite

show abstract

“…Among the different phases in LCs, the nematic phase is the simplest one and has very interesting advantages in the fields of both display and non-display electronic devices [ 157 ]. In addition, the dispersion of NMs, namely QDs, in nematic LCs (NLCs) has gained importance due to the improvement in the properties that QDs dispersion impairs NLCs [ 158 ]. Likewise, in the previous paragraph, the study of the stability and aggregation of pristine and QD-dispersed NLCs was carried out by ζ potential and spectrometric (UV–Vis and fluorescence) measurements, when dispersing CQDs in 4′-heptyl-4-biphenylcarbonitrile [ 158 ], and when oil palm leaf-based carbonaceous QDs (OPL QDs) were dispersed in the commercial nematic mixture E48, a positive (+ve) dielectric anisotropic material with the phase sequence Cr.–19 °C–N–100 °C–Iso was observed [ 157 ].…”

Section: Surface Chemistry Of Qdsmentioning

confidence: 99%

Semiconductor Quantum Dots as Target Analytes: Properties, Surface Chemistry and Detection

et al. 2022

View full text Add to dashboard Cite

Since the discovery of Quantum Dots (QDs) by Alexey I. Ekimov in 1981, the interest of researchers in that particular type of nanomaterials (NMs) with unique optical and electrical properties has been increasing year by year. Thus, since 2009, the number of scientific articles published on this topic has not been less than a thousand a year. The increasing use of QDs due to their biomedical, pharmaceutical, biological, photovoltaics or computing applications, as well as many other high-tech uses such as for displays and solid-state lighting (SSL), has given rise to a considerable number of studies about its potential toxicity. However, there are a really low number of reported studies on the detection and quantification of QDs, and these include ICP–MS and electrochemical analysis, which are the most common quantification techniques employed for this purpose. The knowledge of chemical phenomena occurring on the surface of QDs is crucial for understanding the interactions of QDs with species dissolved in the dispersion medium, while it paves the way for a widespread use of chemosensors to facilitate its detection. Keeping in mind both human health and environmental risks of QDs as well as the scarcity of analytical techniques and methodological approaches for their detection, the adaptation of existing techniques and methods used with other NMs appears necessary. In order to provide a multidisciplinary perspective on QD detection, this review focused on three interrelated key aspects of QDs: properties, surface chemistry and detection.

show abstract

“…An empirical observation demonstrates that agglomeration occurs while ζ potential is lower than the critical value around 30 mV. [108][109][110][111][112] A large ζ potential would be preferred for the CQD dispersion in a polar medium. The typical ζ potentials of CQD capped with organic ligands and halide ligands are 0 and 50 mV, respectively, as shown in Figure 2d.…”

Section: Dispersion Of Cqd Inkmentioning

confidence: 99%

Phase‐Transfer Exchange Lead Chalcogenide Colloidal Quantum Dots: Ink Preparation, Film Assembly, and Solar Cell Construction

Yuan

Wang

Xiao

et al. 2021

Small

View full text Add to dashboard Cite

Colloidal quantum dots (CQDs) are the category of semiconductor nanocrystals with sizes smaller than their exciton Bohr radius. [1][2][3][4][5] Given the nanoscale size, CQDs exhibit strong quantum confinement effect, which induce many unique optical properties such as tunable absorption, with exciton peaks ranging from the ultraviolet to the infrared, to the THz region. [6][7][8][9][10] This size-dependent absorption makes CQDs quite suitable for single-junction and tandem solar energy harvesting. [11][12][13][14][15][16][17][18][19][20][21][22][23][24] Among various synthesis approaches of CQDs, Solution-processed colloidal quantum dots (CQDs) are promising candidates for the third-generation photovoltaics due to their low cost and spectral tunability. The development of CQD solar cells mainly relies on high-quality CQD ink, smooth and dense film, and charge-extraction-favored device architectures. In particular, advances in the processing of CQDs are essential for high-quality QD solids. The phase transfer exchange (PTE), in contrast with traditional solid-state ligand exchange, has demonstrated to be the most promising approach for high-quality QD solids in terms of charge transport and defect passivation. As a result, the efficiencies of Pb chalcogenide CQD solar cells have been rapidly improved to 14.0%. In this review, the development of the PTE method is briefly reviewed for lead chalcogenide CQD ink preparation, film assembly, and device construction. Particularly, the key roles of lead halides and additional additives are emphasized for defect passivation and charge transport improvement. In the end, several potential directions for future research are proposed.

show abstract

Optical properties and zeta potential of carbon quantum dots (CQDs) dispersed nematic liquid crystal 4′- heptyl-4-biphenylcarbonitrile (7CB)

Cited by 59 publications

References 44 publications

Electrochemical control of emission enhancement in solid-state nitrogen-doped carbon quantum dots

Electrochemical control of emission enhancement in solid-state nitrogen-doped carbon quantum dots

Semiconductor Quantum Dots as Target Analytes: Properties, Surface Chemistry and Detection

Phase‐Transfer Exchange Lead Chalcogenide Colloidal Quantum Dots: Ink Preparation, Film Assembly, and Solar Cell Construction

Contact Info

Product

Resources

About