scholarly journals PbS1−xSex-Quantum-Dot@MWCNT/P3HT Nanocomposites with Tunable Photoelectric Conversion Performance

Inorganics ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 87
Author(s):  
He Zhu ◽  
Huilin Hu ◽  
Minheng Ye ◽  
Jinhua Ye ◽  
Defa Wang

The photoelectric performance of quantum dots (QDs)-based nanocomposites is closely related to the optical properties of QDs, which play a critical role in the optical absorption and separation/transfer of charge carriers. Herein, we report a nanocomposite composed of light absorber PbS1−xSex quantum dots (QDs), electron-conducting multiwalled carbon nanotubes (MWCNTs) and hole-conducting poly-3-hexylthiophene (P3HT) with tunable photoelectric conversion performance. In addition to using the quantization effect, we proposed solid-solution PbS1−xSex QDs (x = 0, 0.25, 0.5, 0.75, 1) for band gap engineering. In particular, we successfully synthesized relatively small (~5.3 nm) and uniform QDs via the hot-injection method by using PbCl2, S/Se powder and environmentally friendly oleylamine (OLA) as the precursors and/or solvent. By increasing the content of Se, the band gap of PbS1−xSex QDs decreased along with the decrease in the conduction band and valence band edges. The suitable energy level alignment enabled the efficient transfer of photoinduced charge carriers, and hence a much higher photoelectric conversion performance of the PbS1−xSex-QD@MWCNT/P3HT nanocomposites than the individual QDs, P3HT, and binary PbS1−xSex-QD@MWCNT, as well as the best performance, was achieved over PbS0.75Se0.25-QD@MWCNT/P3HT.

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 419
Author(s):  
Saradh Prasad ◽  
Mamduh J. Aljaafreh ◽  
Mohamad S. AlSalhi ◽  
Abeer Alshammari

The notable photophysical characteristics of perovskite quantum dots (PQDs) (CsPbBr3) are suitable for optoelectronic devices. However, the performance of PQDs is unstable because of their surface defects. One way to address the instability is to passivate PQDs using different organic (polymers, oligomers, and dendrimers) or inorganic (ZnS, PbS) materials. In this study, we performed steady-state spectroscopic investigations to measure the photoluminescence (PL), absorption (A), transmission (T), and reflectance (R) of perovskite quantum dots (CsPbBr3) and ethylene vinyl acetate/terpene phenol (1%) (EVA-TPR (1%), or EVA) copolymer/perovskite composites in thin films with a thickness of 352 ± 5 nm. EVA is highly transparent because of its large band gap; furthermore, it is inexpensive and easy to process. However, the compatibility between PQDs and EVA should be established; therefore, a series of analyses was performed to compute parameters, such as the band gap, the coefficients of absorbance and extinction, the index of refractivity, and the dielectric constant (real and imaginary parts), from the data obtained from the above investigation. Finally, the optical conductivities of the films were studied. All these analyses showed that the EVA/PQDs were more efficient and stable both physically and optically. Hence, EVA/PQDs could become copolymer/perovskite active materials suitable for optoelectronic devices, such as solar cells and perovskite/polymer light-emitting diodes (PPLEDs).


Author(s):  
Bo Li ◽  
Enyan Guo ◽  
Chengxiang Wang ◽  
Longwei Yin

Correction for ‘Novel Au inlaid Zn2SnO4/SnO2 hollow rounded cubes for dye-sensitized solar cells with enhanced photoelectric conversion performance’ by Bo Li et al., J. Mater. Chem. A, 2016, 4, 466–477, DOI: 10.1039/C5TA06889D.


2006 ◽  
Vol 352 (32-35) ◽  
pp. 3633-3635 ◽  
Author(s):  
P.M. Naves ◽  
T.N. Gonzaga ◽  
A.F.G. Monte ◽  
N.O. Dantas

2021 ◽  
Vol 45 (14) ◽  
pp. 6263-6272
Author(s):  
Biyas Posha ◽  
Narayanan Asha ◽  
N. Sandhyarani

A 0D–1D CNQDs/f-CNT architecture composed of 0D CNQDs tethered on a 1D functionalized multiwalled carbon nanotube (f-CNT) network was used for dopamine sensing.


2015 ◽  
Vol 34 ◽  
pp. 73-78
Author(s):  
Irtiqa Syed ◽  
Santa Chawla

A novel one pot synthesis approach in oleic acid medium was employed to obtain monophasic ZnSe quantum dots (QD) of average size 3.7nm. The QDs were well crystalline in hexagonal phase as revealed by x-ray diffraction and high resolution transmission electron microscopy (HRTEM) studies. The ZnSe QDs exhibit sharp emission peak in the blue (465nm) with 385picosecond fluorescence decay time. The theoretical band gap corresponding to 3.7nm ZnSe QDs matched well with the measured 3.11eV band gap of synthesized QDs which thus showed quantum confinement effect.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Oscar A. Mendoza Reales ◽  
Caterin Ocampo ◽  
Yhan Paul Arias Jaramillo ◽  
Juan Carlos Ochoa Botero ◽  
Jorge Hernán Quintero ◽  
...  

Decoupling the individual effects of multiwalled carbon nanotubes (MWCNTs) and surfactants when used as reinforcement materials in cement-based composites is aimed in this study. Powder MWCNTs were dispersed in deionized water using different types of surfactants as chemical dispersing agents and an ultrasonic tip processor. Cement pastes with carbon nanotubes additions of 0.15% by mass of cement were produced in two steps: first, the MWCNT/surfactant dispersions were combined with the mixing water, and then, cement was added and mixed until a homogeneous paste was obtained. Mechanical properties of the pastes cured at 7 days were measured, and their fracture behavior was characterized using the linear elastic finite element analysis. It was found that the reinforcing effect of MWCNT was masked by the negative effect of surfactants in the cement matrix; nevertheless, nanotubes were capable of increasing both stress and strain capacity of the composite by controlling the crack propagation process at the tip of the crack.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Anirban Das ◽  
Eric Hall ◽  
Chien M. Wai

Attachment of PbS quantum dots (QD) to single-walled carbon nanotubes (SWNT) and multiwalled carbon nanotubes (MWCNT) is described; wherein commercially obtained PbS-QD of size 2.7 nm, stabilized by oleic acid, are added to a suspension of single- or multiwalled carbon nanotubes (CNT) prefunctionalized noncovalently with 1,2-benzenedimethanethiol (1,2-BDMT) in ethanol. The aromatic part of 1,2-BDMT attaches to the CNT byπ-πstacking interactions, noncovalently functionalizing the CNT. The thiol part of the 1,2-BDMT on the functionalized CNT replaces oleic acid on the surface of the QD facilitating the noncovalent attachment of the QD to the CNT. The composites were characterized by TEM and FTIR spectroscopy. Quenching of NIR fluorescence of the PbS-QD on attachment to the carbon nanotubes (CNT) was observed, indicating FRET from the QD to the CNT.


Sign in / Sign up

Export Citation Format

Share Document