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Lanthanide ions doped in perovskite (LIDP) nanocrystals (NCs) provide an effective way to utilize the emission of lanthanide metals in a solution‐processable way, combining the theoretical photoluminance quantum yield (PLQY) of ≈200%. To utilize advantages, LIDP‐NCs have inspired studies exploring the fundamental physics of energy transfer, including the up‐conversion or down‐conversion process, and the optoelectronic applications of solar cells and white light‐emitting didoes. This review broadens the scope of LIDP nanocrystal matrix semiconductors in electroluminescence devices in the near‐infrared (NIR) range (>900 nm). A research is summarized on the synergistic effect of lanthanide ions and perovskite matrix in the near‐infrared region, and discuss from the perspective of fabrication of lanthanide‐based electroluminescent devices using perovskite materials as the matrix. The multiple optical transitions, bandgap tunability, and quantum‐cutting effect to provide a tutorial on understanding LIDP‐NCs are started. The details of synthesizing LIDP materials and aim to lay the foundation for preparing NIR electroluminescent devices with high efficiency and application value are then illustrated. The scientific issues that limit the performance of LIDP NCs‐based electroluminescent devices and discuss the potential strategies for the future development of LIDP material are focused on. [ABSTRACT FROM AUTHOR]

Perovskite light‐emitting diodes (LEDs) emitting in the pure‐red range of 630–640 nm show promise in meeting the requirement of the Rec.2100 standard for high‐resolution displays. However, the high‐performing LEDs (external quantum efficiency, EQE >20%) in the pure‐red range suffer from half‐life time (luminance drop to 50% of the initial luminance) of <1.6 h, resulting from the injection/transportation barrier and surface‐defects–induced charge carrier quenching. Herein, a bi‐ligand synergy strategy is developed to address the T50 issue: the introduction of iodide‐rich ligands with different chain length increases the vacancy formation energy of halogen ions and enhances the exciton binding energy, resulting in a high photoluminescence quantum yield of over 92%. The treated CsPbBrx/I3−x films exhibit 34‐fold improved material stability related to the control at continuous aging at 100 °C. As a result, pure‐red LEDs with CIE coordinates of (0.698, 0.301) approaching the Rec.2100 standard are reported. These pure‐red LEDs exhibit a low turn‐on voltage of 1.8 V, which is the lowest among reported pure‐red perovskite LEDs, and even 0.15 V lower than the optical bandgap energy (1.95 eV); and a maximum EQE of ≈21% with fourfold enhanced T50 relative to the best previous pure‐red perovskite LEDs. [ABSTRACT FROM AUTHOR]

Lanthanide ions (Yb3+ or Er3+) alloying of CsPb(Cl1‐xBrx)3 quantum dots (QDs) to emit approaching 1000 nm show promise in near‐infrared light‐emitting diodes (NIR‐LEDs). High Yb3+ alloying ratio increases the electroluminance efficiency of emission at 990 nm and enables high external quantum efficiency (EQE) of NIR‐LEDs, however, the high alloying ratio also results in inferior material stability and PLQY drop because of Yb3+‐induced nanocrystal precipitation. This study finds that the heavy alloying of Yb3+ ions causes lattice distortion and coherent energy reduction of Yb3+: CsPb(Cl1‐xBrx)3 QDs, induced by two Yb3+ ions replacing three Pb2+, which leads to the collapse of the octahedral structure in ambient conditions. It posits that spontaneous monovalent ion (Na+) alloying can address the trade‐off between material stability and emission intensity. The Na+ occupies the vacancy of Pb2+ ions, relaxing the distortion in the lattice and improving the phase stability of octahedral structure, and this optimized structure in turn allows a higher Yb3+ alloying ratio. Stability measurements show that the Na+/Yb3+ co‐alloyed films show ten‐fold higher material stability and 2.0‐fold emission efficiency related to controls. It reports that as a result Na+/Yb3+ co‐alloyed NIR‐LEDs have an EQE of 6.4% at 990 nm, which is among the highest perovskite NIR‐LEDs beyond 950 nm. [ABSTRACT FROM AUTHOR]

To study the characteristics of mtf-1 gene of Siniperca chuatsi and the effects of cadmium stress on the circadian rhythm of mtf-1 gene in brain, we analyzed cis-regulatory elements of mtf-1 gene promoter, sequence characteristics and tissues expression patterns of mtf-1 gene, and explored the circadian rhythm changes of mtf-1 gene expression in brain of Siniperca chuatsi under cadmium stress. The results showed that there were binding sites of zinc finger proteins including ZNF136, ZNF384 and ZNF143 in the mtf-1 promoter of S. chuatsi, indicating that their expression is potentially regulated by metal ions. In addition, RORβ binding sites of the core clock gene were also found in the mtf-1 promoter of S. chuatsi, indicating that the mtf-1 gene is potentially involved in circadian rhythm regulation. The analysis of function domain indicated that mtf-1 gene has a highly conserved DNA binding domain and a non-conserved trans-activation domain. mtf-1 gene is expressed in different tissues of S. chuatsi, among which the highest expression level is found in brain tissue, followed by kidney. Under natural conditions, mtf-1 gene showed a trend of high expression at night and low expression in the brain at day. The expression peak phase occurs at ZT 12.65h (nightfall), which is consistent with its life habits. Under cadmium stress, the mtf-1 gene in the brain of S. chuatsi presented continuous low expression level, and with no significant difference between day and night, indicating that the mtf-1 gene expression in the brain of S. chuatsi could be significantly inhibited by cadmium, and the circadian rhythm of mtf-1 in the brain tissue of S. chuatsi is damaged. [ABSTRACT FROM AUTHOR]

A crown ether-appended calix[2]triazolium[2]arene, which exhibits excellent selectivity for H2PO4− compared to other anions, has been designed and synthesized. The selectivity of the prepared receptor for H2PO4− is caused by the stabilization of H2PO4− by the neighboring triazolium hydrogen bond donors and crown ether hydrogen bond acceptors. [ABSTRACT FROM AUTHOR]