The optical properties of indium phosphide (InP) quantum dots (QDs) are significantly influenced by their surface native oxides, which are generally removed by treating InP cores with hydrofluoric acid (HF). Besides the harmful health effects of HF, its etching may cause over-etching or QD size broadening, and surface oxidation can also reoccur rapidly. In the present study, a safer bifunctional metal oleate treatment was developed to simultaneously remove the surface oxide layer and passivate the surface defects for aminophosphine-based InP QDs. Compared to conventional HF etching, the bifunctional metal oleate was able to more efficiently remove the surface oxide of InP cores and effectively preserve the oxide-free surface, leading to a 20% narrower photoluminescence (PL) bandwidth after growing a ZnSe/ZnS shell. The metal oleate treatment is thus considered a greener and safer post-synthetic method to remove InP surface oxide and provide additional passivation to improve the optical properties of aminophosphine-based InP QDs, which could have potential in industrial mass production.

Spinodal decomposition-based micro phase separation was found in hybrid poly(9,9-dioctylfluorene-alt-N-(4-sec-butylphenyl)-diphenylamine) (TFB) and polyvinylcarbazole (PVK) system, which is used as a hole transporting layer (HTL) in atmosphere-based quantum dot (QD) light-emitting...

Magnesium-doped zinc oxide (MZO) nanoparticles (NPs) with a cubic zinc blende (ZB) structure and with a hexagonal wurtzite (WZ) structure were prepared via a wet-chemical synthetic process by varying the base and used as the electron transport layer (ETL) for electroluminescent (EL) quantum-dot light-emitting diodes (QLEDs). Both as-synthesized MZO NPs were monodisperse with a polydispersity index <0.15 and retained excellent colloidal stability at least for 4 weeks. The formation of a NP film from the MZO NPs to configure the architecture of EL QLEDs resulted in significant enhancement in the charge carrier transport and the EL performance of QDs. It was found that the cubic MZO has more improvement than the hexagonal one on the EL device current density and current efficiency. Furthermore, considering the efficient recombination of electron and hole carrier transport, the conductive molecule tris(4-carbazoyl-9-ylphenyl)amine (TCTA) was added to poly(9-vinylcarbazole) (PVK) to increase the hole mobility. As a result, the EL QLEDs equipped with the combination of cubic MZO/TCTA-PVK carrier transport layers show 5-fold device efficiency and 10-fold brightness as high as 234,400 cd/m2, compared with conventional ZnO/PVK-based devices. This work highlights the potential of the cubic ZB-phase-based MZO film as the electron transport layer and TCTA mixed PVK in developing a solution for high-performance QLEDs.

The existence of optical nonlinear properties in silver-oxide-doped and -undoped germanotellurite glasses by using thermal poling treatment was demonstrated and compared. The variation of second-order nonlinear optical characteristics with poling voltage and their stability with time were observed via the macroscopic second harmonic generation measurement. The study also includes the investigation of enhancement of the nonlinear property by thermally poling K[Nb 1/3 Te 2/3 ] 2 O 4.8 volume-distributed glass-ceramic composite in which the role of silver in ceramic component and the modified surface structure layer of the glass component would be further discussed.