Perovskite-based materials have attracted considerable attention in photoelectric devices. In this paper, we report the one-step fabrication of spin-coated CsPbBr_2.5I_0.5 perovskite films doped with PAN (polyacrylonitrile) polymer. A red perovskite LED (PeLED) composite film was fabricated which featured a maximum luminance value of 657 cd/m² at 8 V. We fabricated white PeLEDs by combining hole transporting layer material emission, perovskite–polymer composite material PAN:CsPbBr_2.5I_0.5, and pure inorganic perovskite CsPbBr₃ as a luminescent layer. The maximum luminance of the device was 360 cd/m² at 7 V, and the color coordinate was (0.31, 0.36). We obtained an ideal white light-emitting device that paves the way for further development of white PeLEDs.

The key to improving the energy conversion efficiency of perovskite solar cells lies in the optimization of the film morphology. The optical and electrical properties of the perovskite film, such as light absorption, carrier diffusion length, and charge transport, are all directly affected by the film morphology. Therefore, this review starts from the perovskite solar cells structure, and it summarizes the state-of-art perovskite film fabrication technologies and the caused film morphology to the performance perovskite solar cells. The spin coating method has an enormous waste of materials and only a small area of the device can be utilized. It is difficult to be used in commercial manufacturing. However, due to the high efficiency of this preparation method, it is irreplaceable in the initial research and development of perovskite materials, and so this method will be popular for a long time in the laboratory. Chemical vapor deposition and thermal vapor deposition have high technical requirements and a good repeatability of processing and manufacturing, and large-scale production can be realized. It may be the first technology to admit industrial application; the scratch coating method and slot-die have significant technical aspects. The similarity of the roll-to-roll manufacturing technology is also an efficient preparation method. Still, to achieve high-efficiency devices, it is necessary to consider the thickness control of each functional layer, and to find or prepare perovskite paste. Finally, we summarized the various fabrication processes and the prospects for the commercialization of perovskite solar cells. We predict that to achieve the commercialization of perovskite solar cells, the existing fabrication technologies should be optimized and more studies should be conducted.

Transparent electrodes (TEs) are important components in organic optoelectronic devices. ITO is the mostly applied TE material, which is costly and inferior in mechanical performance, and could not satisfy the versatile need for the next generation of transparent optoelectronic devices. Recently, many new TE materials emerged to try to overcome the deficiency of ITO, including graphene, ultrathin metal, and oxide-metal-oxide structure. By finely control of the fabrication techniques, the main properties of conductivity, transmittance, and mechanical stability, have been studied in the literatures, and their applicability in the potential optoelectronic devices has been reported. Herein, in this work, we summarized the recent progress of the TE materials applied in optoelectronic devices by focusing on the fabrication, properties, such as Graphene, ultra-thin metal film, and metal oxide and performance. The advantages and insufficiencies of these materials as TEs have been summarized and the future development aspects have been pointed out to guide the design and fabrication TE materials in the next generation of transparent optoelectronic devices.

This paper introduces an X-ray reflective anode with a diamond heat buffer layer, so as to improve heat dissipation of micro-focus X-ray sources. This also aids in avoiding the destruction of the anode target surface caused by the accumulation of heat generated by the electron beam bombardment in the focal spot area. In addition to the description of the production process of the new reflective anode, this study focuses more on the research of the thermal conductivity and compounding ability. This paper also introduces a method that combines finite element analysis (FEA) in conjunction with thermal conductivity experiments, and subsequently demonstrates the credibility of this method. It was found that due to diamonds having a high thermal conductivity and melting point, high heat flux produced in the micro-focus spot region of the anode could be conducted and removed rapidly, which ensured the thermal stability of the anode. Experiments with the power parameters of the radiation source were also completed and showed an improvement in the power limit twice that of the original.

A variable optical attenuator (VOA) is a crucial component for optical communication, especially for a variable multiplexer (VMUX) and reconfigurable optical add-drop multiplexer (ROADM). With the capacity increasing dramatically, a large-port-count and low-power-consumption VOA array is urgent for an on-chip system. In this paper, we experimentally demonstrate a 16-channel VOA array based on a polymer/silica hybrid waveguide. The proposed array is able to work over C and L bands. The VOA array shows an average attenuation larger than 14.38 dB with a low power consumption of 15.53 mW. The low power consumption makes it possible to integrate silica-based passive devices with a large port count on-chip.