Infrared upconversion detectors are devices comprising an infrared photodetector (PD) and a visible light?emitting diode (LED) stacked in series, which directly convert invisible infrared signals into visible emission and enable imaging with CCD or CMOS cameras. Compared with conventional electrical readout schemes, the upconversion approach eliminates readout circuits and complex algorithms, offering simplified fabrication and reduced cost. Colloidal quantum dots (CQDs), with solution processability, tunable bandgaps, and compatibility with diverse substrates, provide a key materials platform for constructing low?cost, large?area upconversion devices that operate at room temperature. This review briefly outlines the operating mechanisms of upconversion devices, defines the key performance metrics of CQD?based upconversion detectors, and systematically surveys recent representative advances in two areas: luminescent?material engineering and device/interface engineering. Finally, we summarize the current status and challenges and propose several research directions.
CdS exhibits excellent photochemical properties and high quantum efficiency in the visible light region, however, its catalytic stability is significantly compromised by photocorrosion. Constructing CdS/Mg?CdIn2S4 heterojunctions can effectively suppress photocorrosion and enhance the material's overall stability. In this study, CdS nanowires (CdS NWs), CdS nanoparticles (CdS NPs), and Mg?CdIn2S4 nanosheets (NSs) were prepared using the ion exchange method, and heterojunctions of 5% CdS NWs/Mg?CdIn?S? (5% by mass fraction of CdS NWs) and 5% CdS NPs/Mg?CdIn?S? (5% by mass fraction of CdS NPs) were constructed. The photocatalysts were characterized using X?ray diffraction (XRD), UV?vis diffuse reflectance spectroscopy (DRS), Fourier?transform infrared (FT?IR) spectroscopy, N2 adsorption?desorption isothermal analysis, transient photocurrent measurements, and electrochemical impedance spectroscopy. The results confirmed the successful construction of both CdS NWs/Mg?CdIn2S4 and CdS NPs/Mg?CdIn2S4 heterojunctions. The catalytic performance was evaluated in a photoreaction system, both heterojunctions possess significant capabilities for the photocatalytic reduction of CO2. Notably, the CdS NWs/Mg?CdIn2S4 heterojunction exhibited superior photocatalytic performance, achieving CO and H2 production rates of 716.7 μmol/(g·h) and 664.3 μmol/(g·h), respectively. These values represent a 46.2?fold and 56.8?fold enhancement compared to pristine Mg?CdIn?S?.Consequently, this work provides a solid foundation for further research and practical applications in the field of photocatalytic CO2 reduction, underscoring significant academic and practical significance.
Ruthenium complexes exhibit considerable potential for application in devices owing to their high photoluminescence quantum yields and tunable emission wavelengths.Nevertheless,traditional solution?processing methods often lead to disordered molecular aggregation,which detrimentally affects both luminescence efficiency and material stability.Conventional vacuum deposition methods involve complicated procedures and high production costs,which hinder the practical utilization and broader adoption of these materials and devices.To address these challenges,this work presents a novel approach for fabricating tris(bipyridine)ruthenium(Ⅱ) complex microcrystalline films.By employing a mixed?solvent approach,the ruthenium complex is guided to self?assemble on the surface of conductive glass,leading to the formation of microcrystalline architectures.Utilizing gallium?indium (Ga?In) alloy as the counter electrode,a simple device capable of high?intensity visible emission was successfully fabricated. Furthermore, patterned electrodes were prepared using molds and liquid metal.Combining these electrodes with the ruthenium complex microcrystalline films enabled the fabrication of devices capable of emitting patterned light.This study offers a promising pathway for the low?cost and large?area manufacturing of ruthenium?based light?emitting devices.
Industrial wastewater treatment has emerged as a significant global challenge. Although physical adsorption offers advantages such as effective contaminant removal and operational simplicity, it often entails high consumption of adsorbent materials and elevated costs. Because of its superparamagnetic, small particle size, large specific surface area and easy recovery characteristics, Fe3O4 shows broad potential in the field of adsorption, but its application alone still has some limitations. This paper aims to review the preparation and application of magnetic composites based on Fe3O4 as a green and efficient adsorbent in wastewater treatment, in order to deal with the current problems of high cost and difficult recovery of adsorption materials. The main synthesis methods for magnetic activated carbon, magnetic cyclodextrin, and magnetic cellulose composites were introduced, followed by an overview of their use in the adsorption of heavy metals and organic pollutants. Additionally, an analysis was conducted on the advancements in the application of magnetic separation and regeneration technologies. The results indicate that Fe3O4 composite material has good performance in adsorption efficiency, environmental protection and cost control. Fe3O4 composites have shown unique advantages as potential adsorbents. It is suggested that Fe3O4 composite adsorption materials with low cost and high adsorption capacity should be further developed to promote its transformation from laboratory to engineering application.