Perovskite, which follows the chemical formula ABX3 and exhibits an octahedral structure, is primarily a hybrid of organic and inorganic materials. It can be broadly categorized into three types based on dimensionality: 0D nanocrystals, quasi- 2D, and 3D bulk structures. As a result, it is gaining attention as a next-generation optoelectronic material for applications in light-emitting devices, solar cells, and sensors. This paper provides insights into dimension of perovskites, their respective synthesis methods, and current research trends, thereby offering prospects for advancements in the study of next-generation optoelectronic materials.

This paper delves into the application of the short-wave infrared (SWIR) region, with a focus on the synthesis and optical characteristics of silver sulfide (Ag₂S) nanostructures. SWIR offers advantages such as reduced damage to biological tissues and enhanced optical transparency, making it valuable across various domains. The study introduces three distinct synthesis methods, each showcasing the ability to obtain nanostructures with improved optical properties. These research findings open up the possibility of providing tailored solutions in detection, imaging, and other applications by controlling the size and ligands of Ag2S nanoparticles. This paper provides new insights into the utilization of Ag₂S in the SWIR region, which is expected to foster advancements in future technologies.

This study investigates the post-thermal treatment effects on the efficiency of silicon heterojunction solar cells, specifically examining the influence of annealing on p-type microcrystalline silicon oxide and ITO thin films. By assessing changes in carrier concentration, mobility, resistivity, transmittance, and optical bandgap, we identified conditions that optimize these properties. Results reveal that appropriate annealing significantly enhances the fill factor and current density, leading to a notable improvement in overall solar cell efficiency. This research advances our understanding of thermal processing in siliconbased photovoltaics and provides valuable insights into the optimization of production techniques to maximize the performance of solar cells.

Direct use of sunlight through the glass windows is an efficient way to reduce the energy consumption related to the heating, cooling, and lighting. Introduction of near-infrared modulating properties through colloidal doped metal oxide nanocrystals into the classical electrochromic materials accelerates the development of next-generation electrochromic devices. There has been a steady enhancement in the performance of electrochromic devices, necessitating a review of the recent progress in next-generation electrochromic devices employing doped metal oxide nanocrystals. This review provides an overview of the current developments in next-generation electrochromic smart windows utilizing colloidal doped metal oxide nanocrystals, with a focus on the key factors for achieving these advanced windows. Colloidal doped metal oxide nanocrystals are a crucial component in realizing and bringing to market the next generation of electrochromic windows, though further research and development are still required in this regard.

Color conversion layer refers to a layer that converts the blue light emitted from the backlight into the red and green light. Heavy metal-free quantum dots and perovskite nanocrystals have attracted great attention as base materials for color conversion layers due to their outstanding optical characteristics. Here, we review recent advances in the development of color conversion layers based on quantum dots. First, we overview the representative optical characteristics of quantum dots and perovskite nanocrystals, and then introduce printing techniques for color converting layers including photolithography, inkjet printing, and nanoimprinting. Finally, we conclude this review with a brief perspective.

TFTs technologies with as high mobility as possible is essential for high-performance large displays. TFTs using nanocrystalline silicon thin films can achieve higher mobility. In this work, the change of the crystalline volume fraction at different hydrogen dilution ratios was investigated by depositing nc-Si:H thin films using PECVD. It was observed that increasing hydrogen dilution ratio increased not only the crystalline volume fraction but also the crystallite size. The thin films with a high crystalline volume fraction (55%) and a low defect density (10¹⁷ cm^-3·eV^-1) were used as top gate TFTs channel layer, leading to a high mobility (55 ㎠/V·s). We suggest that TFTs of high mobility to meet the need of display industries can be benefited by the formation of thin film with high crystalline volume fraction as well as low defect density as a channel layer.

This paper reports the microstructure and electrochemical properties of Si-Al-Fe ternary amorphous alloys prepared by rapid solidification as an anode for lithium secondary batteries. The microstructure was analyzed using XRD and HR-TEM with EDS mapping. In accordance with DSC analysis, annealing was performed to crystallize the active nano-Si in the amorphous alloy. Thus, nano-Si forms (~80 nm) embedded in the matrix alloy, such as Fe₂Al₃Si₃, FeSi₂, and Fe_0.42Si_2.67, were successfully synthesized. The electrode based on the Si-Al-Fe ternary alloy delivered an initial discharge capacity of approximately 700 mAh ^g-1, and exhibited a high Coulombic efficiency of 99.0~99.6% from the 2^nd to 70^th cycles.

With the development of the Internet of Things, the use of flexible displays has become widespread. In particular, the use of curved, bendable, and rollable displays is increasing. Flexible display production processes include various important components such as lamination material, flexible substrates, and adhesives. Among them, improvement of the lamination process comprises a large proportion of efforts for further development. In this paper, we attempt to improve the transmittance of the display substrate by performing a bubble removal process after adhesion. The transmittance of the glass substrate with the bubble removal process was 5~12% higher than that of the substrate without the bubble removal process. The fill-strength after the bubble removal process was improved by 21.4%, and the shear-strength was improved by 43.9%.

Recently perovskite materials with much cheaper cost and marvellous optoelectronic properties have been studied for next generation LED display devices overseas. Technology development trends of inorganic CsPbX₃(X=halogen) based LEDs (PeLEDs) with assumed high stability were investigated on literature worldwide. It was found that syntheses methods of these nanocrystals (NCs, mainly quantum dots, QDs) made great progress. A new room temperature synthesis method showed outstanding PL (photoluminescence) properties such as high quantum yield (QY), narrow emission width, storage stability comparable with, or often exceeding those of conventional hot injection method and CdSe@ZnS type inorganic colloidal QDs. PeLEDs with shell layers might be more promising, indicating urgent real research start of this solution processing technology for small businesses in Korea.

The resistive switching characteristics of resistive random access memory (ReRAM) based onamorphous Ge0.5Se0.5 thin films have been demonstrated by using Ti/Ag nanocrystals/Ge0.5Se0.5/Ptstructure. Ag nanocrystals (Ag NCs) were spread on the amorphous Ge0.5Se0.5 thin film and they playedthe role of metal ions source. As a result, comparing the conventional Ag/Ge0.5Se0.5/Pt structure, thisTi/Ag NCs/Ge0.5Se0.5/Pt ReRAM device exhibits the highly uniform bipolar resistive switching (BRS)characteristics, such as the operating voltages, and the resistance values. At the same time, a stable DCendurance(> 100 cycles), and the excellent data retention (> 104 sec) properties were found from theTi/Ag NCs/Ge0.5Se0.5/Pt structured ReRAM device.

For the application of photo-detector as active layer, we have studied how to deposit SiGe thin film using an independent Si target and Ge target, respectively. Both targets were synthesized by purity of 99.999%. Plasma generators were generated by radio frequency (rf, 13.56 MHz) and direct current (dc) power. When Ge and Si targets were sputtered by dc and rf power, respectively, we could observe the growth of highly crystalline Ge thin film at the temperature of 400℃ from the result of raman spectroscopy and X-ray diffraction method. However, SiGe thin film did not deposit above method. Inversely, we changed target position like that Ge and Si targets were sputtered by rf and dc power, respectively. Although Ge crystalline growth without Si target sputtering deteriorated considerably, the growth of SiGe thin film was observed with increase of Si dc power. SiGe thin film was evaluated as microcrystalline phase which included (111) and (220) plane by X-ray diffraction method.