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Colloidal quantum dots (QDs) are promising building blocks in optoelectronic devices, mainly due to their size/shape/composition‐tunable properties. Core–shell QDs, in particular, offer enhanced stability, mitigated photoluminescence blinking, and suppressed non‐radiative recombination compared to plain QDs, making them highly promising for energy conversion applications such as photovoltaic devices, luminescent solar concentrators, solar‐driven hydrogen production, and light‐emitting diodes. Here, a comprehensive analysis of core–shell QDs in energy conversion technologies is provided. Emerging design strategies are explored and various synthetic methods focusing on optimizing band structure, band alignment, and optical properties are critically explored. Insights into the structure‐property relationship are discussed, highlighting recent advancements and the most effective strategies to enhance energy conversion performance. The review is concluded by addressing key challenges and proposing future research directions, emphasizing the need for rational design, precise synthesis, effective surface engineering, and the integration of machine learning to achieve optimized properties for technological applications. [ABSTRACT FROM AUTHOR]

Quantum dot (QD) color conversion films encapsulated with high barrier films are being applied to wide color gamut liquid crystal displays (LCDs). However, besides the expensive cost of barrier films, the aging of QD films under high temperature and high‐intensity blue light remains unresolved. Here, a QD color conversion film is developed using phase‐change liquid encapsulation suitable for roll‐to‐roll film fabrication. In this method, the QDs are encapsulated in the phase‐change material octadecane, which switches between solid and liquid states in response to temperature changes corresponding to standby and operation of the display, respectively. This process endows the self‐healing of QD ligands (liquid state) and effectively increases the lifespan of QDs under ultraviolet (UV) light. This novel phase‐change liquid encapsulation method significantly improves the UV light resistance and long‐term stability of QD color conversion films compared to conventional solid‐state encapsulation. Under conditions of 60 °C, 90% humidity, and 40 mW cm−2 blue LED backlighting, the phase‐change liquid encapsulated QD color conversion film maintains less than 10% brightness degradation for 680 h. This phase‐change liquid encapsulation technology opens new possibilities for manufacturing more durable QD color conversion films. [ABSTRACT FROM AUTHOR]

The development of cadmium‐free blue quantum dots (QDs) is of paramount importance to the display industry. In this study, high‐quality ZnSeTe/ZnSe/ZnS blue QDs, followed by surface treatment with ZnI2 are initially synthesized. The introduction of ZnI2 passivated the surface defects, resulting in an increase in the fluorescence quantum yield. The time‐resolved photoluminescence (TRPL) demonstrates a significant inhibition of non‐radiative recombination associated with the surface defect state. The density functional theory (DFT) calculation reveals that the binding energy between iodine ions and zinc ions is higher than that between oleate ions and zinc ions, providing a theoretical basis for the effective passivation of the suspended bonds of zinc ions on QDs' surface by iodine ions. Moreover, quantum dot light‐emitting diodes (QLEDs) are fabricated and UV photoelectron spectra (UPS) indicate the hole injection barrier between the hole transport layer and QDs decreases 0.12 eV after QDs being treated by ZnI2, facilitating hole injection. Finally, The ZnI2‐treated QLED demonstrates a 1.57‐fold and 1.82‐fold improvement in Lmax and EQEmax, respectively, reaching 6370 cd m−2 and 9.1%, compared to the pristine QLED. The work serves as a valuable reference for enhancing the performance of cadmium‐free blue QLED. [ABSTRACT FROM AUTHOR]

The high electrical output performance of the phononic crystal (PnC)–based piezoelectric energy harvesting (PEH) system is of great research value in self-powered applications. This work presents the effect of incomplete line defect size on elastic wave energy localization and harvesting. The results show that for a given 7 × 5 supercell when the incomplete line defect reaches the second to sixth layer, the energy localization and harvesting performance show a changing trend of first increasing and then decreasing; when the incomplete line defect reaches the 4th, 5th, 3rd, 2nd, and 6th layers of the supercell, respectively, the performance of PEH systems shows a trend from large to small. Among them, when the incomplete line defect reaches the fourth layer of the supercell, the performance of the PEH system is optimal, and the maximum output voltage and the maximum output electric power are 22.54 V and 12.78 mW, respectively. This work provides valuable insights for improving the performance of PEH devices by using the PnC with incomplete line defects. [ABSTRACT FROM AUTHOR]

In recent years, near‐infrared quantum dots (NIR QDs) have emerged as a promising candidate for biological imaging owing to their strong fluorescence penetrating into biological tissues and high imaging signal‐to‐noise ratio. Among various materials, InP QDs are environmentally friendly and have a relatively narrow bandgap of 1.35 eV, which provides a possibility for their emission wavelength to extend to the near‐infrared region. However, the strong reactivity of the precursor of phosphorus makes it challenging to synthesize NIR InP QDs, as it leads to rapid nucleation of the InP core. Herein, a method of epitaxial growth is reported to synthesize NIR InP QDs. Through high‐temperature nucleation and low‐temperature epitaxial growth, NIR InP QDs larger than 15 nm in size and with an emission wavelength of 807 nm are successfully synthesized. Furthermore, by removing InPOx defects on the surface of the core through HF etching, the quantum yield (QY) is increased from 6% to 12%. Ligand exchange successfully converted oil‐soluble ligands into water‐soluble ones, leading to excellent performance in cell imaging. The study provides a promising approach to the synthesis of desirable NIR InP QDs for use in biomedical imaging applications. [ABSTRACT FROM AUTHOR]

Quantum dot light-emitting diodes (QLEDs) present commercial potential and application prospects in both lighting and display technologies. Blue quantum dots (QDs) possess a substantial bandgap and a profound valence band. The significant potential barrier between blue quantum dots and the hole transport layer leads to an imbalance in charge transfer, thereby adversely impacting the device performance. Self-assembled monolayers are attractive for carrier transport. Here, a dynamic self-assembly method is introduced, doping [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz) into Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) to form electric dipoles at interfaces, realizing better energy level alignment and hole injection rate. The maximum external quantum efficiency rises from 8.77% to 17.26% with 2PACz: PEDOT:PSS strategy, representing a twofold enhancement. This result demonstrates that small molecules undergo dynamic self-assembled bilateral motions during crystallization process, aligning energy levels and passivating interfacial trap states, thereby endowing blue QLEDs with high brightness and high efficiency. This work offers a viable pathway for broader applications of blue QLEDs. [ABSTRACT FROM AUTHOR]

In this work, we report the capacitance recovery behavior in the blue quantum dot light-emitting diode (QLED) by capacitance–voltage (C–V) characterizations. A comprehensive study of the C–V, dC/dV–V, and current density–voltage characteristics of pristine and shelf-aged devices suggests that capacitance recovery is associated with space charge-induced charge accumulation. At lower temperatures, the capacitance recovery in the shelf-aged device is efficiently suppressed due to the difficulty in building up the space charge, which supports our argument. Moreover, the capacitance recovery behavior of QLED only happens at low frequencies (a few hundred hertz), which is related to the time constant for charge accumulation at the selected voltage. Our work shows the effect of space charge on device capacitance and enriches the comprehension of carrier processes in QLED under AC measurement. [ABSTRACT FROM AUTHOR]

To compare the differences in floral composition and functions between the two types of microbiota, ileal contents and feces were collected from Sprague Dawley (SD) rats fed in a conventional or specific-pathogen free (SPF) environment and rats fed a high-fat diet (HFD), and the V3–V4 region of the 16S ribosomal ribonucleic acid (rRNA) gene in these rats was then amplified and sequenced. Compared with feces, about 60% of the bacterial genera in the ileum were exclusive, with low abundance (operational taxonomic units (OTUs) < 1000). Of bacteria shared between the ileum and feces, a few genera were highly abundant (dominant), whereas most had low abundance (less dominant). The dominant bacteria differed between the ileum and feces. Ileal bacteria showed greater β-diversity, and the distance between in-group samples was nearer than that between paired ileum–feces samples. Moreover, the ileum shared various biomarkers and functions with feces (p < 0.05). The HFD and SPF conditions had a profound influence on α-diversity and abundance but not on the exclusive/shared features or β-diversity of samples. The present findings suggested that, under conventional circumstances, fecal bacteria can represent approximately 40% of the low abundant ileal bacterial genera and that dominant fecal bacteria failed to represent the ileal dominant flora. Moreover, fecal flora diversity does not reflect β-diversity in the ileum. [ABSTRACT FROM AUTHOR]

Most previously reported Dirac valley degeneracies in continuous phononic crystal plates originate from Bragg scattering of the structures and generally have only single-band elastic-wave topological edge states. In the present work, a pair of triangular prisms is used in the construction of hexagonal-lattice phononic crystal plates to mimic the dual-band elastic valley Hall effect. Based on the spatial inversion symmetry conditions, which are related to the intrinsic frequencies of the resonators, the valley degeneracies, topological nontrivial bandgaps, and energy band inversion characteristics of multiple resonance modes are investigated by using the finite element method. Edge passbands combining distinct topology phases exist in each of the two nontrivial bandgaps of the ribbon configuration. The full-field simulations for flexural waves in the waveguide structure are demonstrated to support topologically valley-protected edge transmission in both bands, which immunizes the transport against backscattering from large corners and defects in the route. This work provides a reference for valley edge protection in subwavelength continuous elastic plate media and for the manipulation of the elastic waves at multiple frequencies. [ABSTRACT FROM AUTHOR]