Highly stable and luminescent InP/GaP/ZnS QDs with a maximum quantum yield of 85% were synthesized by in situ method. The GaP shell rendered passivation of the surface and removed the traps. TCSPC data showed an evidence for the GaP shell. InP/GaP/ZnS QDs show better stability than InP/ZnS. We studied the optical properties of white QD-LEDs corresponding to various QD concentrations. Among various concentrations, the white QD-LEDs with 0.5 mL of QDs exhibited a luminous efficiency of 54.71 lm/W, Ra of 80.56, and CCT of 7864 K.

We report the first synthesis of colloidal CuInTe2, CuInTe2-xSex gradient alloyed quantum dots (QDs) through a simple hot injection method. We confirmed the composition of synthesized QDs to cationic rich phase of CuIn1.5Te2.5 and Cu0.23In0.36Te0.19Se0.22 with XPS and ICP analysis, and we have also found that the gradient alloyed Cu0.23In0.36Te0.19Se0.22 QDs exhibit greatly improved stability over the CuIn1.5Te2.5 QDs. The solution-processed solar cell based on the gradient alloyed Cu0.23In0.36Te0.19Se0.22 QDs exhibited 17.4 mA/cm(2) of short circuit current density (Jsc), 0.40 V of open circuit voltage (Voc), 44.1% of fill factor (FF), and 3.1% of overall power conversion efficiency at 100 mW/cm(2) AM 1.5G illumination.

A method for the large-scale synthesis of InPZnS alloy QDs was developed, which tune the optical properties by controlling the dodecanethiol to palmitic acid ratio. The control of the surfactant ratio resulted in the change of alloy composition. The absorption and emission peaks showed a blue shift as the amount of DDT increased, which implied the increase of ZnS contents. The alloy structure was confirmed with TEM, elemental analysis, XRD, and XPS; particularly, P 2p peaks for In−P and InP−S bonds in XPS analysis could give clear evidence. The alloy QDs were overcoated with a ZnS shell, and the quantum yields (QYs) were in the range of 20− 45% for all wavelengths. Finally, a cadmium-free QD yield in a single reaction was determined to be 2.74 g. SECTION: Nanoparticles and Nanostructures

PbS colloidal quantum dot (CQD)-sensitized inorganic-organic10 heterojuction solar cells fabricated by using the PbS CQDs cocapped by the oleic acid (OA) and 1-dodecanethiol (DT) ligand showed better device stability with aging time under ambient conditions without encapsulation. Furthermore, the device performance is better than the cell fabricated from PbS CQDs control, easier charge separation because of a large intrinsic dipole moment, and multiple exciton generation. 2 Unlike p-n heterojunction solar cells, sensitized solar cells are constructed using three key components: an electron conductor, a sensitizer, and a hole conductor. This unique 45 feature enables SSCs to attain a high energy conversion efficiency because the electron-hole pairs generated in the sensitizer are quickly separated into the electron conductor and hole conductor, which suppresses the recombination of the generated charge carriers. Accordingly, SSCs based on a 50 metal chalcogenide such as CdS(e), 3 PbS, 4 or Sb 2 S 3 5 have been intensively studied. Among the metal chalcogenides, PbS colloidal quantum dots (CQDs) have attracted great attention because their bandgap to a large extent can be controlled by the quantum 55 confinement effect as a result of their narrow bulk energy bandgap (0.41 eV) and small exciton Bohr radius (18 nm).

This paper presents extremely‐low leakage technologies in low‐temperature polysilicon (LTPS) TFTs. Experimental and physics‐based analysis of leakage currents, emphasizing the effects of process technologies and device design, are described. Small‐geometry TFTs, controlled by optimal LTPS process, dramatically reduce off‐state leakage current (Ioff) by suppressing gate‐induced drain leakage (GIDL) and thermal generation currents, thus potentially offering lower frame rate operations by reducing IC clock power. Numerical device simulations, supplemented by physics‐based analysis, are performed to corroborate the remarkable low‐Ioff experimental results as well as more‐than‐twice enhanced on‐state current (Ion) in optimized LTPS devices.