Application of a Perovskite NIR-LED with Highly Stable FAPbI₃@SiO₂ Core–Shell Nanocomposites in a SPR Sensing Platform

In recent years, the demand for detection and diagnostic methods has consistently risen due to the aging of the population and the increase in the number of patients with chronic diseases. Label-free biomedical detection techniques have emerged as indispensable instruments for diagnosing a variety of diseases. The development of label-free and highly sensitive near-infrared (NIR) biomedical detection technology has attracted considerable attention. As a label-free, swift, and cost-effective analytical technique, it has demonstrated immense potential for a wide range of applications. We successfully assembled FAPbI3 near-infrared perovskite quantum dots (NIPQDs) into SiO2 shells using a rapid room-temperature atmospheric synthesis method, obtaining monodisperse FAPbI3@SiO2 nanocomposites (NCs) with a high photoluminescence quantum yield (PLQY) of 72%. Additionally, the incorporation of hydrophobic multi-branched trioctylphosphine oxide effectively passivated the surface defects of FAPbI3 NIPQDs and suppressed the hydrolysis rate of tetraethoxysilane, enabling the formation of a highly stable and high PLQY nanoscale-particle level within the FAPbI3@SiO2 core–shell structure. Notably, we successfully incorporated FAPbI3@SiO2 core–shell NCs onto InGaN blue chip as NIR excitation light sources for surface plasmon resonance sensing platforms, providing a novel platform for bioanalytical detection. With a detection sensitivity of 6302.5 nm/RIU, the system demonstrated high sensitivity, stability, and dependability. This achievement expands the biomedical research field’s capacity for diagnosis, monitoring, and treatment

Investigations of MoS₂‑Based Self-Powered M–S–M Photodetectors with Low Defect Density and Fast Response and Low-Temperature Characteristics

In this study, a self-powered MoS2 thin-film M–S–M (metal–semiconductor–metal) photodetector driven by Au/Ag asymmetric electrodes was demonstrated. In the previously reported work, the compatibility of photodiode structures and CMOS processes is not as favorable as the M–S–M photodetector. However, the M–S–M photodetector often requires biased operation. In this research, MoS2 films with different layers were synthesized using a thermolysis method and sulfur powders were added during the process to lower the film defect density. We utilized metals with different work functions to fabricate an asymmetric bending of the energy bands at zero bias, achieving the self-powered operation. The fabricated thin-film photodetector device exhibited a responsivity of up to 75 mA/W in a zero-bias mode and an ultrafast rise/fall time of 8.85/0.96 ms. Furthermore, the photodetector proved its application potential by operating effectively at a low temperature of 225 K. This capability makes it highly promising for sensing applications in cold or polar regions

Photophysical and Electrochemical Properties of Blue Phosphorescent Iridium(III) Complexes

A series of 2-difluorophenyl-4-methoxypyridine ligands were synthesized and successfully used to prepare iridium complexes including bis[2-(2‘,3‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a1), bis[2-(2‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a2), bis[2-(2‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a3), bis[2-(3‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a4), and bis[2-(3‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a5). Interestingly, 5a4 exhibits 2‘-coordinated and 6‘-coordinated isomers. The coordination behavior of this ligand with iridium metal differed depending on the repulsion energy and the delocalization energy effects of the iridium complexes. X-ray structural analysis technique was successfully applied to interpret the different coordination behavior of 5a4. In addition, introducing the methoxy group to the well-known ligand (2-difluorophenylpyridine) successfully expanded the band gap of iridium complexes and made 5a2 exhibit the bluest emission at 452 nm. To the best of our knowledge, this is one of the bluest OLEDs based on a 2-difluorophenylpyridine-iridium coordination emitter

Photophysical and Electrochemical Properties of Blue Phosphorescent Iridium(III) Complexes

A series of 2-difluorophenyl-4-methoxypyridine ligands were synthesized and successfully used to prepare iridium complexes including bis[2-(2‘,3‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a1), bis[2-(2‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a2), bis[2-(2‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a3), bis[2-(3‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a4), and bis[2-(3‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a5). Interestingly, 5a4 exhibits 2‘-coordinated and 6‘-coordinated isomers. The coordination behavior of this ligand with iridium metal differed depending on the repulsion energy and the delocalization energy effects of the iridium complexes. X-ray structural analysis technique was successfully applied to interpret the different coordination behavior of 5a4. In addition, introducing the methoxy group to the well-known ligand (2-difluorophenylpyridine) successfully expanded the band gap of iridium complexes and made 5a2 exhibit the bluest emission at 452 nm. To the best of our knowledge, this is one of the bluest OLEDs based on a 2-difluorophenylpyridine-iridium coordination emitter

Photophysical and Electrochemical Properties of Blue Phosphorescent Iridium(III) Complexes

A series of 2-difluorophenyl-4-methoxypyridine ligands were synthesized and successfully used to prepare iridium complexes including bis[2-(2‘,3‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a1), bis[2-(2‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a2), bis[2-(2‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a3), bis[2-(3‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a4), and bis[2-(3‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a5). Interestingly, 5a4 exhibits 2‘-coordinated and 6‘-coordinated isomers. The coordination behavior of this ligand with iridium metal differed depending on the repulsion energy and the delocalization energy effects of the iridium complexes. X-ray structural analysis technique was successfully applied to interpret the different coordination behavior of 5a4. In addition, introducing the methoxy group to the well-known ligand (2-difluorophenylpyridine) successfully expanded the band gap of iridium complexes and made 5a2 exhibit the bluest emission at 452 nm. To the best of our knowledge, this is one of the bluest OLEDs based on a 2-difluorophenylpyridine-iridium coordination emitter

Photophysical and Electrochemical Properties of Blue Phosphorescent Iridium(III) Complexes

A series of 2-difluorophenyl-4-methoxypyridine ligands were synthesized and successfully used to prepare iridium complexes including bis[2-(2‘,3‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a1), bis[2-(2‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a2), bis[2-(2‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a3), bis[2-(3‘,4‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a4), and bis[2-(3‘,5‘-difluorophenyl)-4-methoxypyridinato-N,C2‘]iridium(III) [5-(2‘-pyridyl)tetrazolate] (5a5). Interestingly, 5a4 exhibits 2‘-coordinated and 6‘-coordinated isomers. The coordination behavior of this ligand with iridium metal differed depending on the repulsion energy and the delocalization energy effects of the iridium complexes. X-ray structural analysis technique was successfully applied to interpret the different coordination behavior of 5a4. In addition, introducing the methoxy group to the well-known ligand (2-difluorophenylpyridine) successfully expanded the band gap of iridium complexes and made 5a2 exhibit the bluest emission at 452 nm. To the best of our knowledge, this is one of the bluest OLEDs based on a 2-difluorophenylpyridine-iridium coordination emitter