All inorganic cesium lead halide (CsPbX 3 , X = Cl, Br, I) perovskite nanocrystals (PeNCs) are synthesized by employing polar solvent controlled ionization (PCI) method in precursors. The new strategy can be easily carried out at room temperature and allow to employ smaller amount of weaker polarity and a broader range of low-boiling low-toxic solvents. The as prepared CsPbX 3 PeNCs reveal tunable emission spectra from 380 to 700 nm and high quantum yields over 80% with narrow full width at half maximum (FWHM). Meanwhile, larger "effective Stokes shifts" of PeNCs in PCI method, which enlarges 200% more than other PeNCs in regular methods, are observed. Most interestingly, the PeNCs growth process is coupling with some typical crystals formations. The main morphologies of CsPbI 3 PeNCs are hybrid of nanorods and nanoparticles. The primary morphologies of CsPbBr x I 3-x and CsPbBr 3 PeNCs are nanowires, which are supposed to have great potentials for applying in laser arrays and highly sensitive photodetector applications. Furthermore, such superior optical is endowed to fabricate white light emitting diodes, which has wide color gamut covering up to 120% of the National Television Systems Committee color standard.

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Solution-processed semiconductor nanocrystals are evolving as potential candidates for future display and lighting applications owing to their size-tunable emission, ultrasaturated colors, and compatibility with large-area flexible substrates. Among them, quantum rods (QRs) are emerging materials for optoelectronic applications, offering polarized emission, high light outcoupling efficiency, color purity, and better stability in solid films. However, synthesizing QRs covering the full visible wavelength region has been a big challenge, particularly in the blue range. Herein, we report for the first time the synthesis of red CdSe/CdS, green CdSe/Zn x Cd1–x S/ZnS, and blue CdSe/Zn x Cd1–x S/ZnS QRs and their application in red, green, and blue QR-based light-emitting diodes (QR-LEDs). We have improved the charge injection balance into the QRs through embedding a poly­(methyl methacrylate) (PMMA) layer between the emissive and electron transport layers. The thin PMMA electron-blocking layer (EBL) suppresses the excessive electron flux and thus promotes charge injection balance and pushes the recombination zone back to the QR layer, resulting in 1.35×, 1.2×, and 1.7× peak external quantum efficiency improvement for red, green, and blue QR-LEDs, respectively. The efficiency roll-off of green and blue QR-LEDs with an EBL is less than 50% at maximum current density. The proposed red, green, and blue QR-LEDs open up an avenue toward further improving the light source efficiency and stability focusing on real device applications.

The comparison of optical and electronic properties between squarely and hexagonally arranged nano-porous layers and uniformly arranged nano-wired layers of aluminium and silver was presented. The nano-wired configuration exhibit 20 and 10% higher average transmittance in visible wavelength range in comparison to square and hexagonal nano-porous designs, respectively. The insignificant difference of the transmittance for aluminium and silver nano-porous and nano-wired layers is observed, when interpore/interwire distance is larger than wavelengths of incoming light. This difference becomes considerable at the interpore/interwire distance less than wavelengths of incoming light: silver nano-porous and nano-wired layers possess up to 27% higher transmittance in comparison to aluminium layers.