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Perovskite quantum dots (PeQDs) are seen as the credible alternative to traditional QDs ascolor converter in liquid crystal display (LCD). Unfortunately, PeQDs sufferfrom instability and color separation, and the prepared PeQDs enhanced films(PQDFs) need the protection of expensive barrier layers, which significantly increases price and limits their application. Herein, large‐area yellow monolithic PQDF is fabricated with both green CsPbBr3 and red CsPbBr1I2QDs encapsulated in the dual matrices of inorganic glass and polypropylene (PP) via an industrialized melt extruding & rolling method. The PQDF shows high photoluminescence quantum yield (PLQY) of 92% and narrow full width at half maximum (FWHM) of 19 nm (green) and 33 nm (red). Importantly, the bare PQDF without barrier layers can pass harsh aging test at 85 °C/85% RH and reach anoperating T90 lifetime over 1000 h. Finally, a white backlit unit is designed by coupling yellow monolithic PQDF with blue light guide panel, and the constructed prototype display shows superior color rendering performance forits narrow green/red emissions, reaching a color gamut of 110% National Television System Committee (NTSC). This work provides a novel and easy‐to‐industrialize route to prepare PQDFs to realize their commercial application in backlit display. [ABSTRACT FROM AUTHOR]

Robust amorphous glass protected CsPbBr3 (CsPbBr3@glass) perovskite quantum dots (PeQDs) with ultra‐pure green emission and superior long‐term stability are highly desirable for developing wide‐color‐gamut liquid crystal displays. However, most of the reported CsPbBr3@glass nanocomposites are subject to low external quantum efficiency (EQE). This work demonstrates that ZrO2 additive has an "accumulation" effect on the borosilicate glass network structure to promote in situ nucleation/growth of PeQDs inside glass rather than self‐crystallization. This effect is beneficial in reducing surface defects, improving the quality of PeQDs, and thus boosting radiative recombination of excitons. As a consequence, the as‐prepared CsPbBr3@glass shows a record EQE of up to 75% and can pass the accelerated aging tests at 85 °C/85% RH for 1000 h and blue light irradiation over 2000 h. Finally, a prototype display using CsPbBr3@glass‐based straight‐down backlit unit is designed and gains more favorable responses in blind selection tests for its high brightness of 2647 cd m−2 and high color purity of 88%. The findings will pave the way for realizing the commercial application of CsPbBr3@glass nanocomposite in PeQDs‐converted backlit display. [ABSTRACT FROM AUTHOR]

The complex and high‐precision patterning of perovskite quantum dots (PeQDs) is of vital importance for exploring their new functionalities and device applications. In this work, a strategy based on the combination femtosecond (fs) laser‐irradiation and humidity‐control is reported to construct patterns of cyan CsPb(Cl/Br)3 PeQDs in a transparent glass medium. Benefiting from their ionic crystal feature and low formation energy, CsPb(Cl/Br)3 PeQDs can be locally crystallized and decomposed via fs laser irradiation without further heat‐treatment. More notably, it is found that a water molecule is able to affect the growth of CsPb(Cl/Br)3 PeQDs in glass. By modulation of relative humidity in air, the selectively decomposed perovskite structure is spontaneously regenerated, and the highly emissive CsPb(Cl/Br)3 PeQDs can be in situ manufactured in the confined glass region. This allows for reversible luminescence from the same patterns of laser printing‐erasing‐recovering, and the process can be repeated for multiple cycles without destruction of optical performance and robustness. The results provide a flexible method to develop new encryption/decryption technology for information security and anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

High‐quality backlit display puts forward urgent demand for color‐converting materials. Recently, metal halide perovskites (MHPs) with full spectral tunability, high photoluminescence quantum yields (PLQYs), and high color purity have found potential application in wide‐color‐gamut display. Regrettably, naked MHPs suffer from long‐term instable issue and cannot pass harsh stability tests. Herein, amorphous‐glass‐protected green/red CsPbX3 quantum dots (QDs) are prepared by elaborately optimizing glass structure, perovskite concentration, and in situ crystallization. PLQYs of green CsPbBr3@glass and red CsPbBr1.5I1.5@glass reach 94% and 78%, respectively, which are the highest ones of CsPbX3@glass composites reported so far and comparable to colloidal counterparts. Benefited from complete isolation of QDs from external environment by glass network, CsPbX3@glass can endure harsh commercial standard aging tests of 85 °C/85%RH and blue‐light‐irradiation, which are applied to construct white light‐emitting diodes (wLEDs) with high external quantum efficiency of 13.8% and ultra‐high luminance of 500 000 cd m−2. Accordingly, the perovskite wLED arrays‐based backlit unit and a prototype display device are designed for the first time, showing more vivid and wide‐color‐gamut feature benefited from narrowband emissions of CsPbX3 QDs. This work highlights practical application of CsPbX3@glass composite as an efficient and stable light color converter in backlit display. [ABSTRACT FROM AUTHOR]

Laser‐driven projection display puts forward urgent demand for color converter materials to achieve wide‐color‐gamut and high‐quality image presentation. In this study, a hierarchical structure quantum dots‐in‐glass film (QiGF) is fabricated via co‐sintering stable green/red‐emitting CsPbX3@glass (X3 = Br3, Br1.5I1.5) and commercial low‐melting glass on the sapphire substrate. Benefiting from the well‐retained optical properties of CsPbX3 quantum dots in amorphous glass and high thermal conductivity, QiGF succeeded in inhibiting luminescence saturation after 20 W mm−2 blue laser irradiation. A brand‐new white‐lighting source designed by coupling a blue laser with a pattern "QiGF wheel" produced ultra‐narrow blue/green/red tri‐color emissions and total luminous flux of 146 lm. Accordingly, a QiGF‐converted laser projection system is successfully designed for the first time, showing more natural and real color restoration for its wide color gamut display feature (157% of conventional light‐emitting diode projection and 107% of NTSC standard). The present study highlights the practical application of CsPbX3 quantum dots composite as an efficient laser‐driven color converter in projection display. [ABSTRACT FROM AUTHOR]

Currently, narrowband light‐convertor is critically urgent for preeminent color representation in lighting and display fields, however, the development of target materials still remains challenging. Herein, glass ceramic (GC) composite based on in situ glass crystallization, where the condense glass network structure acts as effective obstructors for long distance ion diffusion, is elaborately designed to inhibit activators' multi‐sites occupation for acquiring narrowband emitting. Following this strategy, an unprecedented narrowband blue emission of Eu2+‐activators with a peak at 447 nm and full‐width of half maximum (FWHM) of ≈30 nm is developed in a new type of Sr5(PO4)3Cl (SPOCl) GC composite. The Eu2+‐activators' hindered diffusion inside the GC composite makes preferential and limit occupation of the [Sr1O9] sites, enabling narrowband blue luminescence. Furthermore, the GC composite highlights remarkable performance in high‐power violet‐excitable full‐spectrum lighting and transparent display (TD) prototype fields, due to its high color purity (≈98.1%), photoluminescence quantum field (PLQY, ≈80.5%) and thermal stability (≈82.1%@150 °C). This work not only promotes the profound understanding of the relationship between light manipulation and glass crystallization, but also paves the way toward the implementation of high‐quality lighting and display of GC composites. [ABSTRACT FROM AUTHOR]

• NIR laser triggered UC emissions in glass-stabilized CsPbX 3 perovskites are realized. • The UC mechanism is radiative energy transfer from Tm: KYb 2 F 7 to CsPbX 3. • Tunable DS/UC combined luminescence is demonstrated via tailoring halogens in glass and selecting diverse excitation modes. • Visualized anti-counterfeits using screen-printable CsPbX 3 inks are practically applicable. • The luminescence of anti-counterfeiting patterns is well retained after storing in water for 30 days. Photon upconversion (UC) of perovskite nanocrystals (PeNCs) is an attractive topic and has been recently realized in colloidal solution. However, this scheme suffers from system instability owing to the easy decomposition of PeNCs, which will greatly limit their applications. This work reports the achievement of radiative energy transfer UC of glass-stabilized CsPbX 3 (X = Cl, Br, I) PeNCs triggered by Tm: KYb 2 F 7 NCs upon 980 nm near-infrared (NIR) laser excitation, which shows the advantages of superior long-term stability and enables them to find practical application. Both CsPbX 3 @glass and Tm: KYb 2 F 7 @glass nanocomposites are fabricated by an in-situ glass crystallization method, and their mixtures yield tunable downshifting/upconverting combined luminescence via tailoring halogen components in glass and selecting diverse excitation modes (UV, NIR or concurrent UV and NIR). Consequently, screen-printing multiple anti-counterfeiting patterns containing ultra-stable CsPbX 3 PeNCs with convenient encryption/decryption and excellent water resistance are experimentally demonstrated, providing a very high level of security. [ABSTRACT FROM AUTHOR]

• Cs 3 LnF 6 NCs@glass nanocomposites have been fabricated via an in-situ glass crystallization strategy. • Yb/Er: Cs 3 LuF 6 NCs@glass yields a maximal upconversion efficiency of ~0.30%. • Er: Cs 3 YbF 6 NCs@glass exhibits a remarkable laser-induced photothermal effect. • The stability of Cs 3 LnF 6 NCs is remarkably improved owing to effective glass protection. • Upconversion photothermal anticounterfeit based on these nanocomposites is demonstrated. Currently, advanced security strategies have aroused widely interest in anti-counterfeiting field to ensure the authentic items difficult to be replicated. Herein, cubic Cs 3 LnF 6 (Ln = Y, Yb, Lu, Sc) nanocrystals embedded glasses are successfully prepared via an in-situ glass crystallization strategy. Emitting centers, such as Eu3+, Er3+, Ho3+ and Tm3+, can be incorporated into the precipitated Cs 3 YF 6 , Cs 3 YbF 6 and Cs 3 LuF 6 crystal lattices but remain in glass matrix rather than in Cs 3 ScF 6 crystals for large ionic radius mismatch between lanthanide activators and Sc3+ host ions. It is demonstrated that upconverting quantum yields of all the Yb/Er: Cs 3 LnF 6 @glass samples are higher than those of well-known cubic/hexagonal Yb/Er: α/β-NaYF 4 @glass samples. Specifically, Yb/Er: Cs 3 LuF 6 @glass exhibits a maximal quantum yield of ~0.30%, which is superior to Yb/Er: β-NaYF 4 @glass (~0.19%). Impressively, Er: Cs 3 YbF 6 @glass shows a remarkable 980 nm laser-induced photothermal effect, leading to significant alteration of upconversion emissive color from red to green with increase of incident laser power. As a prototype of the concept for practical application, a series of luminescent patterns using Er: Cs 3 YbF 6 @glass upconverting inks are constructed by a screen-printing technique and show distinct laser-power-sensitive emissive colors, being feasible for high-level anti-counterfeiting. The present work exploits a new anti-counterfeiting strategy by developing highly efficient laser-induced upconverting photothermal materials. [ABSTRACT FROM AUTHOR]

Laser‐driven projector puts forward urgent demand for light‐conversion materials to achieve high‐quality image display. Herein, a composite structure phosphor‐in‐glass film (PiGF) is fabricated via screen‐printing YAG:Ce and low‐melting glass on the alumina substrate. Benefited from well‐retained optical properties of YAG:Ce in amorphous glass and high thermal conductivity of substrate, PiGF can produce desirable luminous flux of 7169 lm and luminous efficiency of 192 lm W−1 at saturation threshold of 13.25 W mm−2. Furthermore, it is demonstrated that thermal management by using a cool fan with aluminum heat sink is essential to reduce heat aggregation and improve white‐light stability of PiGF‐based laser lighting source operated in a reflective mode. Accordingly, a PiGF‐converted laser projection system is successfully designed for the first time, showing more vivid and brighter display feature benefited from high laser‐driven luminance of LCD screen (2180 cd m−2). This work highlights the practical application of PiGF@alumina‐substrate composite as an efficient laser‐driven color converter in high‐brightness projection display. [ABSTRACT FROM AUTHOR]

Elaborate engineering of emitting wavelength of green down‐converter in the spectral range of ≈525–535 nm with narrow full‐width at half‐maximum (fwhm < 25 nm) is an essential prerequisite for faithfully reproducing colors in the quantum dot (QD)‐based backlit display. Herein, different from the previous complex synthesis for green films, FAPbBr3 perovskite QDs films are fabricated by a dual‐additive assisted in situ growth strategy. Both C6H5CH2CH2NH3+ and 1,4,7,10,13,16‐hexaoxacyclooctadecane additives are introduced to synergistically tune green emitting (≈525–535 nm) with the narrowest fwhm down to 21 nm and the highest photoluminescence quantum yield (PLQY) up to 99%. Improved nanocomposite film with excellent long‐term stability is used to construct a prototype liquid crystal display (LCD) with a wide color gamut (118% National Television System Committee and 88% Recommendation BT 2020), a high saturation, and a remarkable color rendition. The performance is superior to that of the commercial white‐LED‐based LCD, showing a great potential of the present green film for high‐definition display application in the future. [ABSTRACT FROM AUTHOR]

Currently, advanced optical security techniques are imminent in response to the increasingly rampant counterfeit and pirated goods on a global scale. Herein, hexagonal Na(NdxY1−x)F4 (x = 0–1) solid‐solution nanocrystals (NCs) embedded glasses are successfully fabricated via in situ glass crystallization. Benefited from the protection of inorganic glass, Na(NdxY1−x)F4 NCs exhibit superior long‐term stability and can endure high‐power 808 nm laser irradiation. Importantly, opposite variations between near‐infrared (NIR) luminescence and laser‐induced temperature can be detected for the nanocomposites, which are sensitive to Nd3+ doping concentration. As a proof‐of‐concept experiment, Nd3+ concentration dependent anti‐counterfeiting patterns with high‐concealment and high‐precision are designed and show bright emission and dimmish thermal images in Nd3+‐tenuous composites under the irradiation of 808 nm laser, while opposite displays can be achieved in Nd3+‐enriched one. This kind of information encryption triggered by a commercial single light source to achieve dual opposing displays in one material can effectively improve security in anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

CsPbX 3 (X = Cl, Br, I) perovskite quantum dots (QDs) have attracted extensive attention due to their great application prospects in the photoelectronic field. However, the poor long-term stability still limits their practical use. In this work, a whole series of CsPbX 3 QDs were precipitated in a germanate glass matrix by a melt quenching method. The emission wavelength can be tunable in the entire visible spectral region by adjusting of the halide ions and the thermal treatment process. The photoluminescence quantum yield of CsPbBr x I 3-x QDs glass can reach up to 38.24%. The exciton binding energies of CsPbBr x Cl 3-x , CsPbBr 3 and CsPbI 3 QDs glass are about 67 meV, 160 meV and 290 meV, respectively. Additionally, the influence of the thermal treatment temperature on photoluminescence properties of CsPbBr x I 3-x QDs glass was investigated in detail. These results will be of benefitting to their practical applications, such as display devices and WLEDs. • A whole series of CsPbX 3 (X = Cl, Br, I) QDs were precipitated in germanate glass matrix. • Emission wavelength can be tunable in the whole visible spectral region by adjusting the halide ions. • Exciton binding energy of CsPbX 3 QDs glass increases as the halide ions change from Cl to I. • The obtained QDs glass can be potential applications in WLEDs, display devices, etc. [ABSTRACT FROM AUTHOR]

• Ultrapure green emissions of glass-stabilized CsPb(Br/I) 3 PeQDs are fabricated. • Quantum yields of CsPb(Br/I) 3 @glass composites are highly dependent on halogen content. • The emissive profiles and FWHMs can be well modified by varying Br-to-I ratio in glass. • The issues of instability, adverse anion-exchange and phase separation of colloidal PeQDs can be solved by glass protection. • Prototypical white LEDs are constructed and applied in backlit display, covering up 92% color gamut of Rec. 2020 standard. CsPbX 3 (X = Cl, Br, I) perovskite quantum dots (PeQDs) have potential application in backlit display. However, they generally suffer from instability and shortage of ultrapure tunable green emissions owing to halogen phase separation. This work reports the realization of elaborately tunable green emissions in glass-protected CsPb(Br/I) 3 PeQDs, which show the advantage of superior long-term stability and enable them to find promising application in ultra-high definition televisions. CsPbX 3 @glass composites are fabricated by a facile in-situ glass crystallization strategy and their emissions within the spectral range of 506–532 nm along with narrow full width at half maximum (FWHM) of ~21 nm can be well modified by simply varying Br-to-I ratio in precursor glass. Benefited from the protection of tight glass network, CsPbX 3 @glass retains 90% luminescence after immersing in water for one month, shows no any loss of luminescence after irradiation by 450 nm LED light and prevents anion-exchange and phase separation completely. As a proof-of-concept experiment, CsPbX 3 @glass-based on-chip white LED devices are constructed and applied in backlit display, covering up 123% and 92% color gamut of NTSC and Rec. 2020 standards in the CIE 1931 color space, respectively. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots are considered an ideal alternative to traditional phosphor color converters because of their excellent optical properties. However, the bottleneck problem of instability has tremendously limited their practical applications. In the present work, we fabricate green-emitting CsPbBr 3 @glass and red-emitting CsPbBr 1.5 I 1.5 @glass nanocomposites via an in-situ nucleation/growth method. Importantly, the CsPbX 3 @glass (X 3 = Br 3 , Br 1.5 I 1.5) samples exhibit striking thermal reversibility in the heating/cooling cycle experiments. Furthermore, CsPbX 3 monolithic films with high photoluminescence quantum yields (PLQYs) of 80–95% and narrow full-width at half-maximum (FWHM) down to 16 nm are achieved by dispersing ground CsPbX 3 @glass particles in polydimethylsiloxane (PDMS) matrix. Benefiting from dual encapsulation of inorganic glass matrix and organic polymer matrix, the film can endure harsh accelerated aging tests (at 85 °C/85%RH for 500 h). Finally, combining the as-prepared yellow monolithic film with blue chips as the backlight endows the liquid crystal display (LCD) with a wide color gamut (a color gamut of 146% of commercial LCD, 101% of NTSC after passing the color filters), demonstrating great prospects in the display industry. • CsPbX 3 (X 3 = Br 3 , Br 1.5 I 1.5) QDs were in-situ precipitated inside glass matrix via controlling nucleation/growth process. • CsPbX 3 monolithic films exhibited high PLQY of 80–95% and FWHM down to 16 nm. • The CsPbX 3 @glass@PDMS composite films possessed extremely excellent moisture and heat resistance. • A white LED backlit unit was simply achieved by coupling a yellow composite film with blue chips. • The color gamut of screen reached 101% NTSC 1953 standard and 146% commercial LCD after passing the color filters. [ABSTRACT FROM AUTHOR]

Efficient antiviral drug discovery has been a pressing issue of global public health concern since the outbreak of coronavirus disease 2019. In recent years, numerous in vitro and in vivo studies have shown that 25-hydroxycholesterol (25HC), a reactive oxysterol catalyzed by cholesterol-25-hydroxylase, exerts broad-spectrum antiviral activity with high efficiency and low toxicity. 25HC restricts viral internalization and disturbs the maturity of viral proteins using multiple mechanisms. First, 25HC reduces lipid rafts and cholesterol in the cytomembrane by inhibiting sterol-regulatory element binding proteins-2, stimulating liver X receptor, and activating Acyl-coenzyme A: cholesterol acyl-transferase. Second, 25HC impairs endosomal pathways by restricting the function of oxysterol-binding protein or Niemann-pick protein C1, causing the virus to fail to release nucleic acid. Third, 25HC disturbs the prenylation of viral proteins by suppressing the sterol-regulatory element binding protein pathway and glycosylation by increasing the sensitivity of glycans to endoglycosidase. This paper reviews previous studies on the antiviral activity of 25HC in order to fully understand its role in innate immunity and how it may contribute to the development of urgently needed broad-spectrum antiviral drugs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effective Ni2+ doping in CsPbI 3 nanocrystals is achieved. • Ni2+ doping enables to stabilize cubic CsPbI 3 up to 7 months in atmosphere. • Ni2+ doping leads to significantly improve PLQY approaching near-unity. • Ni2+-doped perovskite LED outperforms the device using pristine CsPbI 3 nanocrystals. • The device exhibits a peak EQE of ~7% and a maximal luminance of 830 cd/m2. Room temperature phase instability of cubic CsPbI 3 perovskite nanocrystals is one of the notorious limitations for practical applications in optoelectronic fields. Herein, the incorporation of Ni2+ ions into CsPbI 3 lattice was successfully achieved by a modified hot-injection method using nickel acetate as doping precursor. The as-prepared Ni2+ (3.3 mol%): CsPbI 3 nanocrystals exhibited an improved, near-unity (95%~100%) photoluminescence quantum yield owing to the enhanced radiative decay rate and the decreased non-radiative decay rate. Additionally, Ni-doping was demonstrated to stabilize CsPbI 3 lattice and the Ni2+: CsPbI 3 film and colloidal solution can retain their red luminescence up to 15 days and 7 months in atmosphere, respectively. First-principle calculations verified that the significantly improved optical performance and stability of Ni2+: CsPbI 3 nanocrystals arose primarily from the increased formation energy due to the successful doping of Ni2+ in CsPbI 3. Benefiting from such an effective doping strategy, the as-prepared Ni2+-doped CsPbI 3 perovskite nanocrystals can function well as efficient red-light emitter toward the fabrication of high-performance perovskite LED with a peak external quantum efficiency of ~7%. [ABSTRACT FROM AUTHOR]