Near-infrared (NIR) emitters are essential for night-vision imaging and interference-resilient optical wireless communication yet engineering efficient NIR emission in Mn-based metal halides remains challenging due to the sensitivity of Mn-Mn pair centers to local structure and defects. Here, a hydrothermal synthesis of Cs2MnCl4 single crystals exhibiting a broadband NIR emission (700-900 nm, 780 nm peak) from Mn-Mn coupled centers is reported. Bi3+ dopant engineering introduces an additional UV excitation channel and locally perturbs the host lattice, shifting the emission balance toward Mn-Mn pair centers while suppressing the visible monomer Mn2+ channel, and boosting the photoluminescence quantum yield from 3% for pristine Cs2MnCl4% to 19% for Cs2MnCl4:Bi. A phosphor-converted LED prototype delivers broadband NIR electroluminescence for night-vision imaging, and a proof-of-concept optical link maintains clear image transmission under strong indoor lighting interference. These results demonstrate that trace Bi doping effectively tunes Mn-Mn-coupled NIR emission and improves the applicability of Mn-based halide phosphors in NIR imaging and indoor optical communication.

Mn4+-doped fluoride phosphors exhibit excellent red monochromaticity and high luminous efficiency, giving them broad application prospects in lighting and backlight displays. However, their practical development is limited by prolonged luminescence decay times, and there remains a lack of research on the regulation of their excitation response characteristics, which severely restricts their utility in variable-input optical information systems. Here, we report a Mn4+-doped A2BF6-type fluoride red phosphor with an average lifetime of 2.8 ms synthesized based on a lattice engineering strategy, where Li is employed as the A-site ion and Hf as the B-site cation. The design-synthesized Li2HfF6:Mn4+ exhibits two well-resolved excitation bands at 376 and 487 nm that produce the same narrow-band red emission at 633 nm with distinctly different excitation efficiencies, enabling excitation-selective regulation within a single emission channel. By coupling wavelength-addressable excitation with differentiated temporal responses, a programmable optical encoding strategy is achieved for excitation-selective fingerprint identification. More importantly, combining the short-decay emission of Li2HfF6:Mn4+ with the long-decay emission of K2SiF6:Mn4+ (tau = 9.07 ms), a monochromatic multiplexing anti-counterfeiting system in the millisecond regime is realized, allowing rapid and highly secure machine-readable decoding. Furthermore, by integrating the as-synthesized Li2HfF6:Mn4+ phosphor with a 460 nm chip, the as-fabricated phosphor-converted LED enables efficient optical signal transmission over a distance of 10 m. In comparison with the LED assembled using a commercial K2SiF6:Mn4+ phosphor, the present system exhibits a wider modulation bandwidth (12.9 MHz) and a faster data transmission rate (20 Kbps).

Rare-earth oxide (REO) nanomaterials are promising photonic platforms, yet their practical emission efficiency is limited by the intrinsically weak absorption of parity-forbidden 4f-4f transitions. Here, we report a coumarin-based molecular sensitization strategy that markedly enhances the photoluminescence of Eu-doped Y2O3 nanoplatelets by addressing ligand-oxide interfacial chemistry. Using four coumarin derivatives with identical chromophore backbones but varied anchoring-group acidities, we reveal that interfacial chemical compatibility, rather than energy-level alignment alone, governs sensitization efficiency. Strongly acidic carboxylic acid groups induce surface reconstruction and defect formation, leading to pronounced nonradiative quenching, whereas ester and phenolic hydroxyl functionalities enable stable surface anchoring while preserving oxide lattice integrity. The optimal ligand, ethyl 7-hydroxycoumarin-3-carboxylate (EHC), delivers a 149-fold increase in Eu3+ emission by suppressing defect-mediated nonradiative pathways without compromising the structural integrity of the oxide lattice. Furthermore, the coexistence of fast, broadband ligand S1 emission and slow, narrowband Eu3+ emission within a single hybrid nanomaterial enables a proof-of-concept demonstration of dual-channel optical signal routing and information encryption. Our work establishes that beyond conventional energy-level matching, interfacial chemical compatibility serves as a crucial design principle for molecularly sensitized REO nanomaterials, providing guidance for the development of robust, efficient, and multifunctional rare-earth nanophotonic emitters.

In this work, a series of ultra-wide yellow emitting Ba3Sc2(BO3)4:Eu2+ (BSBO:Eu2+) phosphors were prepared by solid state reaction method. Under 338nm excitation at room temperature, the as-prepared BSBO:0.03Eu2+ phosphor exhibits a yellow emission band centered at 575nm with an ultra-wide spectral extending from 450 to 850nm (FWHM = 140nm). Notably, the FWHM of this phosphor demonstrates a temperature-dependent behavior in the range of 298-483K. Based on this unique property, a high precision fiber optic temperature measurement device was fabricated, demonstrating the feasibility of BSBO:Eu2+ phosphors for non-contact temperature sensing applications.

Two-dimensional (2D) materials, with a tunable band structure, strong light-matter interaction, and unique carrier transport, are promising candidates for high-performance photodetectors. Here, high-quality InAs single crystals grown via van der Waals epitaxy coupled with an asymmetric metal-semiconductor structure enable efficient charge separation and photocurrent generation without external bias. Self-powered broadband photodetection based on quasi-2D InAs single crystals is demonstrated by breaking the inversion symmetry. At room temperature, the devices achieve a self-driven broadband photoresponse (300-1100 nm) with high responsivity (0.6 A/W), rapid rise/decay times (73.8/94 μs), and outstanding detectivity (2.3 × 1012 Jones) under zero bias. This work demonstrates that the asymmetric channel in quasi-2D InAs enables efficient charge separation, offering a promising route to high-performance self-powered photodetectors (SPPD).

Silver-containing glasses combine chemical versatility and optical functionality, making them attractive platforms for photonic applications where surface plasmon resonance (SPR) can be exploited to manipulate local electromagnetic fields. When silver species coexist with rare-earth activators, plasmonic near-fields can markedly influence excitation and radiative processes, but the outcome depends sensitively on silver speciation, size distribution, and spatial relationships to the emitters. Bi 2 O 3 −B 2 O 3 −SiO 2 glasses are particularly well suited to such studies because their high polarizability and structural tolerance allow relatively large dopant loadings while maintaining glass stability. Most prior studies have predominantly focused on the low silver doping range (<5mol%), where silver nanoparticles can serve as plasmonic sensitization centers to enhance rare-earth luminescence. However, within the high silver doping range, Ag 0 nanoparticles, Ag + ions, and sub-nanoclusters may coexist simultaneously, and their influence on optical behavior has yet to be systematically elucidated. In this study, we define “anomalous luminescence” as the non-monotonic variation in Dy 3+ luminescence intensity and fluorescence lifetime observed in Dy 3+ -doped Bi 2 O 3 −B 2 O 3 −SiO 2 glasses with AgCl concentrations as high as 9 mol%, relative to their low-concentration behavior. We focus on investigating the aforementioned anomalous luminescence behavior of Dy 3+ under high Ag content conditions (AgCl up to 9 mol%), along with its correlation to microstructure, chemical state, and energy transfer mechanisms. This study elucidates the competitive mechanism between plasmon-enhanced luminescence and concentration quenching.

Nonlead molecular ferroelectrics combining high-temperature ferroelectricity and efficient self-powered photoresponse are desirable for next-generation eco-friendly optoelectronic devices. However, the design and synthesis of such materials remain challenging. Herein, a zero-dimensional (0D) bismuth-based hybrid perovskite, [C4N2H14][BiBr5], was synthesized via a hydrothermal method. Single-crystal X-ray diffraction analysis reveals that this compound crystallizes in the polar space group P21. The intensity of its second harmonic generation (SHG) is 1.20 times that of potassium dihydrogen phosphate (KDP). It features a high ferroelectric Curie temperature (Tc) of 529 K and a decomposition temperature of 597 K, indicative of good thermal stability from experimental characterization. Room-temperature (RT) ferroelectric hysteresis measurements reveal a saturation polarization (Ps) of 0.372 μC/cm2. A direct bandgap of 2.75 eV has been revealed by theoretical calculations and spectral analysis. Bulk ferroelectric photovoltaic effect has been detected under AM 1.5G illumination, delivering a short-circuit current density (Jsc) of 1.86 nA/cm2 and an open-circuit voltage (Voc) of 0.031 V. Critically, ferroelectric polarization modulation enhances the photocurrent density by 62-fold, reaching 114.63 nA/cm2. This work demonstrates the integration of high-temperature ferroelectricity and efficient self-powered photoresponse in a 0D nonlead hybrid system, offering a feasible strategy for developing eco-friendly self-powered photodetectors.

ABSTRACT Optical thermometry is highly attractive for harsh‐environment sensing, yet its accuracy and reliability are constrained by conventional single‐parameter readouts, motivating the development toward multi‐parametric optical thermometry. Here, we report an ultra‐high temperature sensitive Ga 3+ ‐doped Zn 0.8 Cd 0.2 S phosphor based on defect engineering. The photoluminescence quantum yield (PLQY) is boosted from 0.2% to 63.9% by Ga 3+ doping, accompanied by strong and continuous thermal response over an ultrabroad temperature range (–193°C to 200°C). The defect‐tailored emission enables high‐performance, multi‐parametric optical thermometry based on emission intensity, spectral bandwidth, and peak position. This approach delivers a maximum relative sensitivity ( S r ) of 3.4%°C −1 based on intensity, alongside high absolute sensitivities ( S a ) of 0.4°C −1 from bandwidth and 0.7°C −1 from peak position, with a minimum experimentally measured temperature uncertainty ( δT ) of 0.03°C at 15°C. Mechanistic analysis reveals that defect‐mediated recombination pathways coupled with strong electron–phonon interactions underpin the exceptional thermal responsiveness. The as‐explored Zn 0.8 Cd 0.2 S:Ga phosphors have been successfully assembled into a portable fiber‐optic sensor with 98% repeatability, establishing defect engineering as an effective paradigm for highly sensitive, self‐validated multi‐parametric optical thermometry under extreme conditions.

ABSTRACT 2D molecular ferroelectrics have attracted much attention due to their advantages such as low cost, easy processing, and structural tunability. However, the impacts of alkyl chain length on their bandgap, ferroelectric, and photoelectric properties remain unclear. Herein, we present a novel 2D molecular ferroelectric [C 6 N 2 H 18 ]PbI 4 with a P c polar monoclinic structure, a direct bandgap of 2.30 eV, a room‐temperature ferroelectricity with a maximum polarization ( P m ) of 3.5 µC cm −2 . Remarkable polarization‐enhanced photoelectric performance has been achieved, yielding a maximum V oc of ∼ 0.72 V and J sc of ∼ 5.62 µA cm −2 . The impacts of chain length of diverse alkylamines spacer cations on bandgap, ferroelectric, and photoelectric of the homologous APbI 4 system (A for 1,4‐diaminobutane, 1,6‐hexamethylenediamine, and 1,8‐diaminooctane) have been systematically investigated. The elongation of alkyl chain length induces a gradual decline in P m , while simultaneously expanding the optical bandgap and notably enhancing device stability. This work provides a new perspective for the performance optimization of 2D molecular ferroelectrics toward next‐generation optoelectronic devices.

Zn-based halides have garnered much attention because of their high stability and environmental friendliness. In anti-counterfeiting applications, fluorescent materials with low cost, low toxicity, and tunable multicolor emission are highly desired. In this work, we demonstrate that diverse emission colors can be achieved by doping various ions into lead-free C3ZnBr5, forming Cs3Zn1-xCuxBr5-x (x = 0.01-0.06), Cs3Zn1-xMnxBr5(x = 0.10-0.50) and Cs3-xZn1-xCexBr5 (x = 0.05-0.30) series. Copper doping induces blue emission centered at 460 nm with an FWHM of 80 nm; manganese doping yields green emission at 520 nm with an FWHM of 40 nm; and cerium doping produces ultraviolet emission around 382 nm with an FWHM of 70 nm. Leveraging the unique photoluminescent properties of Zn halides, we successfully applied the synthesized materials for anti-counterfeiting. Our results highlight that Zn-based halides as a promising family of lead-free phosphors for advanced optoelectronic and security applications.

Optical thermometry is highly attractive for harsh-environment sensing, yet its accuracy and reliability are constrained by conventional single-parameter readouts, motivating the development toward multi-parametric optical thermometry. Here, we report an ultra-high temperature sensitive Ga3+-doped Zn0.8Cd0.2S phosphor based on defect engineering. The photoluminescence quantum yield (PLQY) is boosted from 0.2% to 63.9% by Ga3+ doping, accompanied by strong and continuous thermal response over an ultrabroad temperature range (-193 degrees C to 200 degrees C). The defect-tailored emission enables high-performance, multi-parametric optical thermometry based on emission intensity, spectral bandwidth, and peak position. This approach delivers a maximum relative sensitivity (S-r) of 3.4%degrees C-1 based on intensity, alongside high absolute sensitivities (S-a) of 0.4 degrees C-1 from bandwidth and 0.7 degrees C-1 from peak position, with a minimum experimentally measured temperature uncertainty (delta T) of 0.03 degrees C at 15 degrees C. Mechanistic analysis reveals that defect-mediated recombination pathways coupled with strong electron-phonon interactions underpin the exceptional thermal responsiveness. The as-explored Zn0.8Cd0.2S:Ga phosphors have been successfully assembled into a portable fiber-optic sensor with 98% repeatability, establishing defect engineering as an effective paradigm for highly sensitive, self-validated multi-parametric optical thermometry under extreme conditions.

All-inorganic CsPbI3 perovskite nanocrystals (NCs) are attractive for backlight displays due to their narrow FWHM, high PLQY, and tunable bandgap, but their poor environmental/thermal stability remains a critical bottleneck for commercialization. Herein, we address this issue by engineering ZnO-modulated borosilicate glasses to host CsPbI3 NCs, via high-temperature melting-quenching followed by post-thermal treatment, with ZnO contents tailored from 5 to 30 molar ratio. ZnO functions as a dual-role network modifier: it optimizes the BO/NBO ratio in the glass matrix to facilitate ion migration, while Zn2* segregates at NC grain boundaries passivate surface defects. This synergy enhances the crystallinity and size uniformity of CsPbI3 NCs. The optimal sample (10 molar ratio ZnO) exhibits uniformly dispersed NCs (3.86 +/- 0.5) nm, a PLQY of 32.99%, an average lifetime of 33 ns, and retains 96% luminescence intensity after 180 days of humid storage. When integrated as red color-conversion layer in wLED (white light-emitting diode) backlight modules, the LCD device achieves 121% NTSC color gamut, outperforming conventional YAG: Ce-based systems. This work clarifies the structure property-stability correlation of ZnO-modulated perovskite glasses, offering a scalable route to highperformance, stable perovskite-based backlight materials.

Few studies have been conducted on enhancing photoluminescence properties through modulation of lattice structure in rare-earth-doped tungstate ceramics. Here, we employed the solid-state sintering method to prepare Ca1-xSrxWO4: Er3+ ceramics. The introduction of Sr2+ results in local lattice expansion and an increase in grain density, which alleviates internal stress concentration, reduces the formation of voids and scattering of luminescent ions, thereby enhancing the luminescence intensity. The tunable ranges of photoluminescence intensity at 530 nm and 552 nm reach as high as 403.9% and 465.8% for x = 0.05, respectively. All the ceramic samples exhibit excellent thermal stability of fluorescence. After the introduction of Sr2+, the green fluorescence intensity of the material was significantly enhanced and exhibited excellent fluorescence lifetime. Our work provides an effective method for adjusting the luminescence of rare-earth-doped tungstate ceramics by incorporating alkaline earth metals to alter the matrix structure, thereby improving the utilization efficiency of mineral structural materials.

Optical pressure sensing offers non-contact readout, rapid response, and immunity to electromagnetic interference. Most luminescent gauges, however, suffer luminescence quenching under high pressure, undermining their reliability in extreme environments. Here, we adopt Eu3+-doped Sc1.5Al0.5W3O12 (SAWO:Eu3+), a zero-thermal-expansion (ZTE) oxide, as a model host and apply a strategy that couples a pressure-induced lattice phase change with deliberate modulation of the Eu3+ activator sites to develop a phosphor that resists high-pressure quenching. In situ high-pressure experiments reveal an orthorhombic-to-monoclinic phase transition, accompanied by a rise in the lattice-distortion index from 0.72% to 2.83% and a 7-fold enhancement of the Eu3+ red emission at similar to 7.2 GPa. The ZTE framework suppresses thermally activated multiphonon relaxation, enabling the phosphor to deliver a normalized photoluminescence (PL) intensity of 105% of its room-temperature value at 175 degrees C. Leveraging the pressure-induced luminescence enhancement, we fabricated an optical warning device that delivers reliable high-pressure alarms.

CsPbI3 nanocrystals were precipitated in situ within Al3+- and Gd3+-modified borosilicate-zinc glass through melt-quenching and subsequent heat treatment. Structural and spectroscopic analyses reveal that Al3+ acts primarily as a network former, consuming nonbridging oxygens and strengthening the glass network, which suppresses excessive crystal growth and produces more uniform nanocrystals (∼4.49 nm) with enhanced luminescence and prolonged lifetime. In contrast, Gd3+ serves as a network modifier, partially relaxing the rigid glass framework and promoting nanocrystal growth. The resulting lattice distortion and strengthened quantum-confinement effect contribute to a blue shift in emission. Benefiting from the synergistic roles of Al3+ and Gd3+, the optimized sample (CPIAG0.4) exhibits a photoluminescence quantum yield of 31.29% together with excellent thermal and moisture stability, retaining its emission intensity after prolonged water immersion. A white LED fabricated from this material achieves a color gamut of 125.2% of the NTSC 1953 standard, while its application as an X-ray scintillation screen delivers a spatial resolution of 14 LP mm-1. These results highlight cooperative ion doping as an effective strategy for engineering perovskite nanocrystal glasses for photonic and imaging applications.

The development of full-spectrum white LEDs is significantly hindered by the “cyan gap” in the 470-510 nm spectral region. Addressing this gap with moderate -quality cyan-emitting phosphors, efficiently excited by violet LED chips, is crucial for achieving high color rendering index (Ra > 90) illumination. In this study, a novel and moderate efficient garnet-structured cyan-emitting phosphor Ca2LuZr2Al1.5Ga1.5O12:Ce3+ (CLZAGO:Ce3+) was effectively prepared via a high-temperature solid-state reaction route. When excited at 410 nm, the optimized CLZAGO:0.04Ce3+ sample displays a robust cyan emission peaking at 484 nm, accompanied by a broad emission band spanning 420-650 nm and a full width at half-maximum (FWHM) of 90 nm, which efficiently fills the cyan gap commonly observed in conventional White light-emitting diodes (WLEDs). The phosphor exhibits available thermal stability, preserving 53% of its room-temperature emission intensity at 423 K, and achieves a moderate external quantum efficiency (EQE) of 45.43%. Finally, when CLZAGO:Ce3+ was combined with commercial blue-emitting Sr5(PO4)3Cl:Eu2+ (SPOC:Eu2+), green-emitting (Ba, Sr)2SiO4:Eu2+ (BSSO:Eu2+), and red-emitting CaAlSiN3:Eu2+ (CASN:Eu2+) phosphors and integrated into a 410 nm violet LED chip, a full-spectrum WLED with an enhanced Ra of 95 was achieved. These findings underscore the critical role of CLZAGO:Ce3+ as a promising cyan-emitting component for next-generation high color-rendering full-spectrum WLEDs.

A novel green-emitting phosphor, Ca2HfSi4O12:Ce3+, Tb3+ (CHSO:Ce3+, Tb3+), was successfully fabricated via a conventional solid-state reaction under high-temperature conditions. The phosphor shows two broad excitation bands (200-400 nm), which can be attributed to the characteristic 4f -> 5d electronic transitions of Ce3+ ions. As an efficient sensitizer, Ce3+ transfers absorbed ultraviolet energy to Tb3+ ions, resulting in a strong green luminescence peaking at 543 nm when excited at 330 nm. The optimized composition, CHSO:0.02Ce3+, 0.035Tb3+, exhibits high internal quantum efficiency (IQE) of 88.65% and external quantum efficiency (EQE) of 54.0% under 330 nm excitation, together with excellent luminous thermal stability, maintaining 90% of its emission intensity at 393 K. White light-emitting diodes (WLEDs) were assembled using CHSO:Ce3+, Tb3+ in conjunction with a 310 nm UV chip and commercial blue BaMgAl10O17:Eu2+ and red (Ca, Sr)AlSiN3:Eu2+ phosphors, yielding a high color rendering index (Ra = 90.2) and a correlated color temperature of 5157 K. These findings highlight CHSO:Ce3+, Tb3+ as an efficient and thermally stable green phosphor with significant potential for UV-pumped WLED applications.

In this study, a novel green-emitting fluorapatite phosphor Ca9Tb(PO4)5(SiO4)F2:Ce3+ (CTPSF:Ce3+), which features excellent luminous efficiency and thermal stability, was first designed and prepared. High-concentration doping of Tb3+ enables efficient green emission. Moreover, photoluminescence (PL) spectra and diffuse reflectance spectra reveal that the introduction of Ce3+ extends the excitation spectrum to the range spanning 200 nm-380 nm, with a significant improvement in efficiency, which stem from the Ce3+ -> Tb3+ energy transfer process. The introduction of Ce3+ boosts the photoluminescence intensity of CTPSF by 2.315-fold, delivering a great internal quantum efficiency (IQE) of 73.95 % and an external quantum efficiency (EQE) of 57.86 %. Additionally, the thermal stability improved from retaining 66.3 % of the original intensity at 150 degrees C to 83.6 % retention of its original intensity at 150 degrees C. Finally, White-light-emitting diode (WLED) devices were fabricated by employing BaMgAl10O17:Eu2+ (blue), CaAlSiN3:Eu2+ (red), and the synthesized CTPSF:Ce3+ (green) phosphors. Upon applying a forward bias current of 60 mA, the WLED device displayed a high color rendering index (Ra) of 92.7 and a low correlated color temperature (CCT) of 3973 K, validating the potential of this greenemitting phosphor for practical applications in WLED lighting systems.

To creating versatile light-emitting materials that enable diverse functionalities, a Mn4+-activated La2MgNbO6.5 multifunctional phosphor that exhibits excellent comprehensive performance for applications in plant lighting and optical thermometry was synthesized. The crystal structure and luminescent characteristics were systematically analyzed. The synthesized La2MgNbO6.5:Mn4+ shows a broadband excitation band spanning 300-500 nm and delivers far-red emission centered near 708 nm, which overlaps with the PFR phytochrome absorption of plants. Furthermore, the enhancement effect of alkali-metal ions on the performance of La2MgNbO6.5:Mn4+ has been investigated. The optimized La2MgNb0.994O6.5:0.006Mn4+, 0.003Li+ phosphor exhibits remarkable improvements in photoluminescence intensity, external quantum efficiency and thermal stability. Its external quantum efficiency reaches an impressive 50.3%, fully meeting the demands of practical applications. An LED device was fabricated by integrating the optimized La2MgNb0.994O6.5:0.006Mn4+, 0.003Li+ far-red phosphor with a 410 nm chip. Wheat-seedling cultivation under its illumination demonstrated markedly enhanced stem growth, further validating the phosphor's potential as a far-red-emitting material for indoor plant-growth LED lighting. Meanwhile, the excellent temperature-dependent luminescence behavior of the phosphor also renders it promising for optical thermometry. Its nearly linear response trend enables potential practical applications, yielding a high relative sensitivity of up to 3.3656%& sdot;K-1, and a minimum temperature uncertainty as low as 0.0165 K. The results demonstrate that the Mn4+-activated La2MgNbO6.5 multifunctional phosphor possesses broad application prospects in both plant lighting and optical thermometry.