Visible-to-ultraviolet C (UVC) up-conversion phosphors are promising materials for remote sterilization applications. In this work, Pr³⁺-doped Ba2SiO4 phosphors were synthesized and investigated under 450 nm excitation. The up-conversion luminescence properties were characterized and compared with those of Pr³⁺-doped Y2SiO5 and LiYF4. Strong UVC emission in the 240-350 nm range was observed, and the up-conversion mechanism was attributed to excited-state absorption and energy-transfer processes involving Pr³⁺ 4f–5d transitions. The UVC emission power density and conversion efficiency were evaluated under different excitation powers. Compared with Y2SiO5: Pr3+ and LiYF4: Pr3+, Ba2SiO4: Pr3+ exhibited significantly enhanced UVC output. Bactericidal experiments further demonstrated effective bacterial inactivation under 450 nm excitation, while direct visible-light irradiation showed negligible sterilization effects. These results indicate that Ba2SiO4: Pr3+ is a promising visible-light-driven UVC up-conversion phosphor with potential applications in sterilization and disinfection.

Lead-free halide perovskites have drawn considerable interest, owing to their low-toxicity and favorable photophysical characteristics. However, achieving efficient near-infrared (NIR) emission often suffers from a trade-off between the red shift and quantum yield. Herein, we report a synergistic host-dopant strategy in zero-dimensional Cs2-xRbxInBr5 & centerdot;H2O perovskites. Controlled Rb+ alloying induces lattice contraction, which unexpectedly weakens electron-phonon coupling and suppresses nonradiative decay, leading to a high photoluminescence quantum yield (PLQY) of 53.2%. Subsequently Mn2+ doping further passivates defect states, boosting the PLQY to 67.5%. Density functional theory calculations and temperature-dependent spectroscopy elucidate the role of the lattice strain in regulating self-trapped exciton emission. A prototype NIR phosphor-converted light-emitting diode (pc-LED) fabricated from the optimized material demonstrates a promising performance in night-vision imaging and plant growth applications. This work provides a viable design strategy for efficient and stable NIR phosphors via a coupled lattice and defect engineering.

Zero-dimensional manganese halides offer distinctive luminescence but are limited by nonradiative losses, constraining their efficiency and tunability. Herein, we demonstrate a synergistic Zn2+ and Sb3+ doping strategy in (C8H20N)2MnCl4 to overcome these limitations. Initial Zn2+ alloying optimized the inter-Mn2+ distance, suppressing nonradiative energy transfer and boosting the inherent green Mn2+ emission (525 nm) to a 92.5% PLQY. Subsequent incorporation of trace Sb3+ ions created dual emissive centers, enabling broad white-light emission and a record PLQY of 98.4%. Combined spectroscopic and computational studies confirm that Sb3+ occupies both Mn2+ and Zn2+ sites, introducing specific defect states that steer energy into both triplet and singlet self-trapped exciton channels, alongside the Mn2+ transition. The optimized material exhibits superior thermal stability with a high activation energy barrier. Leveraging these properties, we fabricated a mechanically durable fluorescent film that serves as a highly sensitive temperature sensor (maximum relative sensitivity of 5.190% K-1), withstanding rigorous folding tests. This work establishes a potent doping paradigm for engineering high-performance 0D emissive halides and showcases their viable integration into flexible optoelectronic devices for advanced sensing applications.

Self-assembly of lead halide perovskite nanocrystals into long-range ordered superstructures can achieve reorganization of the morphological and chiroptical properties. Here, an efficient method is reported to achieve highly intrinsic chiral amplification in aqueous perovskite nanocrystals (PNCs) through freezing-induced strong H-bond driving self-assembly into asymmetric superstructures. The aqueous PNCs with a high photoluminescence quantum yield (PLQY) of 92% are successfully synthesized by the water-assisted strategy. Low temperature enhanced hydrogen bond network regulates the freezing-induced self-assembly of PNCs into asymmetric superstructures in aqueous solution, notably enhancing intrinsic circularly polarized luminescence (CPL) emission with over 200-fold amplification of dissymmetry factor (g lum), along with the g lum of 4.1 & times; 10-3 at 253 K. The emission wavelength of CPL could be tunable by anion exchange in aqueous solution. Our finding offers a pioneering insight into efficiently amplifying intrinsic chiroptical response in low-symmetry perovskites, opening a new avenue for the design of novel self-assembly perovskite materials with superior optical properties and CPL character.

Abstract Systematic strategies for modulating trap distributions through B-site cation engineering in metal halide phosphors remain elusive. Here, we employ density functional theory to guide the isovalent substitution of Cd2+ with Zn2+ in Cs3Cd2Cl7:Sb3+ afterglow phosphors. By leveraging the electronegativity difference and ionic radius mismatch between Zn2+ and Cd2+, we perturb the local bonding environment while preserving the [SbCl6]3– emission framework. Zn2+ incorporation modifies the local structural and electronic environments, while thermoluminescence spectroscopy reveals a broadened trap distribution. The optimized composition, Cs3Cd1.95Zn0.05Cl7:0.04Sb3+, exhibits prolonged afterglow exceeding 180 s-substantially longer than that of the undoped counterpart, while maintaining green self-trapped exciton (STE) emission centered at 518 nm. These engineered defects enable multimode optical readout via thermal stimulation, 980 nm photostimulation, and X-ray excitation. This work establishes a clear correlation between B-site cation identity and defect energetics, providing actionable design principles for next-generation optical storage materials.

The extensive use of antibiotics in medical practices has led to significant adverse effects on environmental equilibrium and human health. Near infrared (NIR) photocatalysts with environmental friendliness, high stability, ease of recovery, and suitability for large-scale production, show great promise for the treatment of organic wastewater. In this paper, a near-infrared-responsive Er3+/Yb3+ co-doped bismuth-based glass-ceramic (GC) photocatalyst were prepared by traditional melt crystallization method, and the best heat treatment condition is crystallization at 700 °C for 3 h BaVO3 and Bi2(VO5) were introduced into the GC, and then BiOCl nanosheets were grown on GC surface by in-situ etching. Under 980 nm excitation, the GC samples exhibited strong green (545 nm) and red (659 nm) emission, and its optical absorption edge extended to 556 nm. The degradation rate of norfloxacin (NOR) of GC photocatalyst (BBVB-GC700–0.15HCl) was 53.58 % under NIR irradiation for 150 min. The GC photocatalyst has good degradation performance, reproducibility, simple preparation processes and low cost, which provide a novel strategy for the large-scale manufacturing and development of efficient photocatalysts.

Halide perovskite materials have garnered considerable interest due to their distinctive optical properties and their promise in optoelectronic applications. In this study, we reported the synthesis novel zero-dimensional halide perovskite Cs3In2Cl9:Te4+ via an ultrasonic-assisted method. The structural and photoluminescent properties of the resulting polycrystalline sample were meticulously characterized using X-ray powder diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and fluorescence spectroscopy. Experimental findings reveal that upon excitation with near-ultraviolet light at 390 nm, the Cs3In2Cl9:Te4+ sample exhibits a bright orange-yellow emission centered at 585 nm, primarily attributed to self-trapped exciton (STE) luminescence. Temperature-dependent emission spectra and decay curves imply that the material holds great potential for temperature sensing applications, showcasing a maximum relative sensitivity (Sr) of 6.27 % K- 1 at 300 K within the range of 300-350 K. Moreover, the Cs3In2Cl9:Te4+ material has been found to possess outstanding thermal and color stability, maintain its integrity through multiple heating and cooling cycles as well as during extended measurement periods. This reliability is crucial for the development of fluorescence-based temperature detection technologies.

This study presents the synthesis of Mo4+-doped Cs4ZnBi2Cl12 double perovskite through a hydrothermal method, demonstrating efficient near-infrared (NIR) emission at 1110 nm with a full width at half maximum (FWHM) of 45 nm. The emission originates from the d-d transition of Mo4+ ions within an octahedral crystal field. Structural analysis using powder X-ray diffraction (PXRD) confirms the phase purity and lattice contraction as a result of Mo4+ substitution at Bi3+ sites, supported by X-ray photoelectron spectroscopy (XPS) and elemental mapping. The material exhibits broad excitation compatibility (348-590 nm) and achieves a photoluminescence quantum yield (PLQY) of 45.3% with a microsecond-scale lifetime of 6.78 μs. Thermal stability tests demonstrate sustained emission intensity (58% at 420 K) and resilience to prolonged heating or UV exposure. This work highlights Mo4+-doped Cs4ZnBi2Cl12 as a stable and efficient NIR emitter, advancing lead-free perovskites for optoelectronic applications in bioimaging, agriculture, and sensing.

Fluorescence intensity ratio (FIR) technique has been a promising non-contact thermometry method owing to the characteristics of rapid response and exceptional resolution. In this study, a new iodate phosphor NaYI4O12:Er3+ (NYIO:Er3+) is synthesized via a microwave-assisted hydrothermal method. It exhibits bright green emission under 380 and 980 nm excitations. The power-dependent upconversion and Er3+ content-dependent downshifting performances are investigated. Excited by 380 nm, the temperature-dependent FIR originating from thermally coupled levels of Er3+ are discussed in detail. The resulting material displays outstanding temperature sensing properties across the temperature range of 298-523 K. The absolute and relative sensitivities can reach the maximum values of 0.51 x 10-2 K- 1 and 1.3 % K-1, separately. Meanwhile, the reliability and repeatability of the temperature sensing characteristics are verified. The result demonstrates that the Er3+-activated iodate phosphor NaYI4O12:Er3+ is a promising candidate in non-contact optical thermometry domain.

The development of environmentally friendly narrow-band green emitters processing high efficiency and strong stability is crucial for optoelectronic applications. In this study, we present series lead-free organic-inorganic hybrid [(CH3)4N]2MnxZn1-xCl4 single crystals. Through the strategic incorporation of Zn2+ into Mn-based metal halides, we have an exceptional 92.5 % photoluminescence quantum yield (PLQY) at x = 0.6, mainly due to the mitigation of Mn concentration quenching effects. Notably, the Zn-alloyed [(CH3)4N]2Mn0.6Zn0.4Cl4 exhibits a remarkable anti-thermal quenching effect, showcasing a 40 % enhancement in integrated emission intensity at 400 K compared to room temperature. Density functional theory (DFT) calculations elucidate that this phenomenon is attributed to the Zn-induced reduction in Cl vacancy formation energy and the suppression of electron-phonon coupling, collectively enhancing radiative recombination efficiency under thermal conditions. The improved thermal and chemical stability of the material enables the fabrication of white light-emitting diodes (WLEDs) with a color coordinate of (0.3086, 0.3373), a luminous efficacy of 45.72 lm/W, and consistent performance under a 350 mA current. This study provides valuable atomic-level understandings of defect engineering and carrier dynamics, facilitating the creation of high-performance Mn-based luminescent materials.

Manganese (Mn)-based organic-inorganic metal halides (OIMHs) are extensively employed in various optical applications due to their non-toxicity, superior optical properties, and tunable emission advantages. Developing effective strategies to enhance the optical properties of these materials and clarifying their structure-optical property relationships continue to be of significant interest. Here, we report that the zero-dimensional (0D) (C24H20P)2MnBr4 exhibits remarkable pressure emission tuning that shifts from green to red, a phenomenon driven by the enhancement of the crystal field splitting energy and the reduced energy difference of the lowest d-d transition (4T1 -> 6A1) motivated by the shortening of Mn-Br bonds. Additionally, the band gap value of (C24H20P)2MnBr4 becomes 3.13 eV, showing an unexpected decrease by 1.09 eV from an initial value of 4.22 eV, when the pressure is released from 31.0 GPa. The incomplete recovery of the distortion in [MnBr4]2- tetrahedra, impeded by the distortion of soft organic macromolecules, is believed to be responsible for band gap narrowing. Combined with computations and subsequent experiments, it is inferred that pressure induced reduction in the Mn-Br bond distance contributes to the distortion of tetrahedral [MnBr4]2- and larger-sized organic cations. Our work not only elucidates the structure-optical property relationships in Mn-based OIMHs, but also opens new avenues for modulating their optical properties and devising innovative strategies for designing novel Mn-based OIMHs.

This study presents the synthesis of Mo 4+ ‐doped Cs 4 ZnBi 2 Cl 12 double perovskite through a hydrothermal method, demonstrating efficient near‐infrared (NIR) emission at 1110 nm with a full width at half maximum (FWHM) of 45 nm. The emission originates from the d‐d transition of Mo 4+ ions within an octahedral crystal field. Structural analysis using powder X‐ray diffraction (PXRD) confirms the phase purity and lattice contraction as a result of Mo 4+ substitution at Bi 3+ sites, supported by X‐ray photoelectron spectroscopy (XPS) and elemental mapping. The material exhibits broad excitation compatibility (348–590 nm) and achieves a photoluminescence quantum yield (PLQY) of 45.3% with a microsecond‐scale lifetime of 6.78 μs. Thermal stability tests demonstrate sustained emission intensity (58% at 420 K) and resilience to prolonged heating or UV exposure. This work highlights Mo 4+ ‐doped Cs 4 ZnBi 2 Cl 12 as a stable and efficient NIR emitter, advancing lead‐free perovskites for optoelectronic applications in bioimaging, agriculture, and sensing.

With the increase in global carbon emissions, environmental problems are becoming increasingly severe. Photocatalytic CO2 reduction, as a green technology, holds promise for converting CO2 into fuels and achieving carbon cycling, thus attracting much attention. The novel BiOIO3 has a suitable band structure, high separation efficiency of photogenerated carriers, and strong CO2 adsorption and activation capabilities, showing significant advantages in the field of photocatalytic CO2 reduction. In this study, a defect engineering modification strategy for BiOIO3 was carried out by means of ultraviolet light irradiation at room temperature and pressure. This achieved flexible regulation of the band structure of photo-induced oxygen vacancy containing BiOIO3 and enhanced its photocatalytic CO2 reduction performance. Through a series of experimental characterizations and DFT theoretical calculations, the formation mechanism of photo-induced oxygen vacancies and the electron transfer behavior of oxygen vacancies in the photocatalytic CO2 reduction reaction were revealed. It was demonstrated that photo-induced oxygen vacancies can effectively improve the utilization efficiency of carriers and enhance CO2 adsorption and activation. The research findings provide a new perspective for defect engineering in the design and application of energy conversion materials.

Differing from traditional near-infrared (NIR) light sources that are made from thermal radiation of a blackbody or filtered light from gas discharge, the technique by converting blue emission of light-emitting diode (LED) chips into NIR light provides a solution. For this purpose, the NIR phosphor should be developed at first. In this work, we report a phosphor Zn2InGaO5:Cr3+, synthesized at 1450 degrees C for 5 h in air ambient, applicable for NIR LED light sources for application at low temperature no higher than 200 K. The Zn2In0.98Cr0.02GaO5 phosphor and the Zn2InGaO5 host have a direct band gap of about 3.00 and 3.03 eV, respectively, and belong to the class of bandgap semiconductors. Excited by 471 nm at room temperature, the phosphor gives ultrabroadband emission, peaked at 826 nm with a full width at half-maximum (FWHM) of 192 nm, in the region of 700-1100 nm. The luminescence intensity increases as the temperature increases from 10 to 200 K, maximizes at 200 K, and then decreases as the temperature increases further, showing an anomalous temperature-quenching effect. Meanwhile, the emission peak blue-shifts continuously from 826 to 779 nm. The output power of the NIR pc-LED device packaged using the Zn2InGaO5:Cr3+ phosphor driven under the current of 100 mA at room temperature is 5.14 mW, for which the photoelectric conversion efficiency is 1.9%.

Zero-dimensional lead-free metal halides have emerged as promising alternatives for optoelectronic applications, yet their thermal quenching behavior and limited spectral tunability remain challenging. Herein, a zerodimensional (0D) antimony-based halide is reported, (C12H28N)2SbCl5, exhibiting anomalous negative thermal quenching (NTQ) and pressure-driven multicolor cycling. The crystal demonstrates near-unity photoluminescence (PL) quantum yield at room temperature and exceptional thermal stability to 518 K. Remarkably, an NTQ effect (80-250 K) arises from thermally activated defect to self-trapped exciton (STE) energy transfer, countering nonradiative losses. Under high pressure, in situ photoluminescence reveals reversible emission color cycling and a 200 % intensity enhancement at 3.2 GPa, attributed to [SbCl5]2- pyramidal distortion, bandgap narrowing, and selective STE state modulating. Density functional theory calculations confirm that lattice compression shorten Sb-Cl bonds, reduces electron-phonon coupling, and stabilizes metastable STEs. Practical applications are demonstrated in high-resolution latent fingerprint imaging under UV light and as stable plantgrowth LEDs, where the emission spectrum optimally matches chlorophyll absorption. This work provides fundamental insights into defect-mediated STE dynamics and establishes a dual-stimuli-responsive platform for tunable luminescence in optoelectronics and imaging technologies.

The near infrared (NIR) photocatalyst with low cost, good stability, easy recovery and large-scale manufacturing has a wide application prospect in the field of organic wastewater degradation. In this paper, Er3+/Yb3+ codoped near-infrared glass-ceramic (GC) photocatalyst were prepared by traditional melt crystallization method, and the best treatment condition is crystallization at 900 degrees C for 3 h. Single molecular layer perovskite Ba5Ta4O15 and BiTa7O19 were introduced into GC, and then BiCl3O12 nanosheets were grown on GC surface by in-situ etching. Under 980 nm excitation, the GC samples mainly showed strong red (659 nm) emission. The BET surface area of the GC sample increased from 0.4676 m2/g to 47.2599 m2/g before and after etching. The photodegradation intermediates were identified by LC-MS and the possible degradation paths of norfloxacin (NOR) were analyzed. The degradation rate of NOR of GC photocatalyst (BTBS-GC900-0.2HCl) was 60 % under near-infrared irradiation for 150 min. The GC photocatalyst has good degradation performance, reproducibility, simple preparation process and low cost, which provides a new idea for large-scale manufacturing and development of efficient photocatalysts.

The advancement of efficient near-infrared (NIR) phosphors with ultra-broadband emission is critical for next-generation NIR light sources in emerging fields like bio-imaging, night vision, and non-destructive inspection. Herein, we report a novel zero-dimensional (0D) hydrate perovskite, Cs2InCl5 center dot H2O:Mo4+, featuring isolated [MoCl5H2O]- octahedra as highly efficient NIR emitters. The unique 0D structure, confirmed by Rietveld refinement and HRTEM, minimizes inter-octahedral interaction and concentration quenching by isolating Mo4+ centers. Benefiting from the tailored octahedral coordination and Jahn-Teller distortion, Mo4+ exhibits ultra-broadband NIR emission centered at 837 nm with a large full width at half maximum (FWHM) of 155 nm and a remarkable internal quantum efficiency (IQE) of 56.7 % under 300 nm excitation. The emission originates from the spin-orbit coupling-enhanced d-d transition of Mo4+, supported by a small Huang-Rhys factor (S = 1.88) and DFT calculations revealing reduced bandgap and impurity states. The material demonstrates exceptional thermal stability and environmental robustness. Fabricated NIR phosphor-converted LEDs (pc-LEDs) achieve an output power of 121 mW and successfully enable non-destructive applications, including fruit bruise detection and printed circuit board inspection, highlighting its practical potential for high-performance NIR spectroscopy.

The development of efficient, thermally stable, and broadband near-infrared (NIR) phosphors is critical for next-generation smart devices yet remains challenged by limited quantum efficiency and spectral coverage in existing systems. Here, we introduce a breakthrough strategy via crystal field distortion engineering in zero-dimensional Cs2ZnCl4, achieving unprecedented Mo4+-activated broadband NIR emission centered at 960 nm with a fwhm ∼ 206 nm. Unlike conventional octahedral hosts, the tetrahedral Zn2+ site in Cs2ZnCl4 undergoes a distortion-driven transformation to an octahedral Mo4+ coordination upon doping, facilitated by Cs vacancies and Jahn-Teller effects. This unique structural reorganization enables a remarkable internal quantum efficiency of 78.7%. The material exhibits thermal stability and environmental robustness. Leveraging these properties, we fabricate NIR phosphor-converted LEDs (pc-LEDs) with a peak output power of 132 mW at 350 mA, demonstrating high-contrast imaging for fruit bruise detection and night vision. This work not only establishes a new paradigm for activator-centered lattice distortion to unlock efficient NIR luminescence but also expands the frontiers of 4d transition-metal-ion applications in optoelectronics.

The exploration of near-infrared light-emitting lead-free perovskite materials has hitherto manifested their remarkable optical properties. Nevertheless, the constraints imposed by the relatively low quantum yield and narrow bandwidth have circumscribed their extensive applications. Here, we report that the Sb3+-doped 0D allinorganic metal halide Cs3In2Cl9 (Cs3In2Cl9:Sb3+) crystals, which are synthesized via an ultrasonic-assisted method, exhibit an unprecedentedly broad bandwidth concomitant with a high quantum yield. Under 330 nm excitation, Cs3In2Cl9:0.07Sb3+ peaks at 730 nm with a photoluminescence quantum yield of 84.2 % and a full width at half maximum (FWHM) of 195 nm, where the NIR emission mechanism can be explained by a selftrapped exciton model. These Cs3In2Cl9:Sb3+ crystals are further proven with high thermal and ultraviolet light (UV) stability. In addition, an NIR light-emitting diode device based on Cs3In2Cl9:Sb3+ demonstrates its potential as a non-visible light source in the applications of information encryption and night vision applications. This research thus puts forward a viable strategy for the development of intelligent halide perovskite materials with high-performance characteristics. Specifically, by employing lead-free cesium-indium halide as the host matrix, it paves the way for their practical applications in diverse fields.