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Quadruple-mode emitting carbon nanodots (QM-CDs) have been designed via an ionic crystal confining strategy. The results reveal that the high-density ionic bonds can inactivate the nonradiative defect centers, stabilize triplet excitons, increase the cross-sectional absorption and boost the chemiluminescence resonance energy transfer of the QM-CDs, endowing their efficient fluorescence, upconversion photoluminescence, phosphorescence, and chemiluminescence simultaneously. And the confining aggregation of CDs in the NaOH matrix contribute to the tunable light emission wavelength. With the QM-CDs, one kind of all-photonic multiple-inputs logic gates with programmable emitting modes have been established to achieve information processing and security. [Display omitted] • The QM-CDs with tunable multiple-mode light emitting are prepared. • The high-density ionic bonds endow the multiple-mode light emitting of QM-CDs. • The confining aggregation endow the tunable light emission wavelengths of QM-CDs. • The programmable multiple-inputs logic gates are established with the QM-CDs. Multiple-mode light emitting in one material system is tremendous desirable for various applications. Herein, we have developed an ionic crystal confining strategy to prepare the carbon nanodots (CDs) with quadruple-mode light emitting and demonstrated their promising application in information anti-counterfeiting via optical logic gates. In detail, the quadruple-mode light emitting of CDs (QM-CDs) are prepared with the citric acid and urea with NaOH matrix via microwave-assisted polymerization. Mechanically, the high-density ionic bonds stemmed from the NaOH ionic-crystal can effectively inactivate nonradiative defect centers, stabilize triplet excitons, increase absorption cross-section and boost resonance energy transfer, evoking the outstanding solid-state fluorescence, upconversion photoluminescence (UCPL), phosphorescence, and chemiluminescence simultaneously. Meanwhile, the isolated NaOH matrix can promote the confining aggregation of CDs, leading to the redshifted emission wavelength and endowing the light emitting with tunable wavelength. With the excitability of logic functions between the light emitting and controlled excitation, the programmable multiple-inputs logic gates are established with the QM-CDs, enabling the application in high-throughput logical operations and information anti-counterfeiting. This research provides a new insight into the synthesize of multiple-mode luminescent CDs, and thus promote the applications of nanomaterials in intelligent encryption and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Creation of the hybrid nanostructures with superior properties that combine the advantages of hardest diamond and flexible graphite remains challenging in experiment. Here we report a new strategy for the synthesis of diamond-graphite hybrid nanocomposite from multi-walled carbon nanotubes fibers by laser heating diamond anvil cell. A combined theory experiment approach confirms the formation of diamond-graphite hybrid structure with the coherent interface consisted of covalent bonds between diamond and graphite. This opens an avenue for the synthesis of diamond-graphite hybrid structure, which may be extended to generate new carbon nanocomposites using other suitable carbon precursors by high pressure. Image 1 [ABSTRACT FROM AUTHOR]

• Ag/ND/g-C 3 N 4 photocatalyst was synthesized for the first time. • Ag/ND/g-C 3 N 4 showed enhanced photocatalytic activity both in H 2 evolution from water splitting and degradation of organic pollution. • The Ag/ND/g-C 3 N 4 exhibited good photostability after four-run test. • The photocatalytic reaction mechanism was illustrated in detail. Efficient separation of photogenerated carriers and light harvesting are the two key factors for high photocatalytic performance. In this work, a novel double-heterojunction silver/nanodiamond/graphite-carbon nitride (Ag/ND/g-C 3 N 4) structured photocatalyst has been synthesized. In comparison to single-heterojunction Ag/g-C 3 N 4 , the double-heterojunction Ag/ND/g-C 3 N 4 photocatalyst presents with a 4.9-times enhancement in H 2 evolution from water splitting and 2.4-times promotion in degrading organic pollution under visible-light irradiation. Furthermore, the Ag/ND/g-C 3 N 4 exhibits good photostability after four-run test. The enhanced photocatalytic activity can be attributed to the synergetic effect of surface plasmon resonance from Ag, optical confinement from ND and suitable band alignment in the double-heterojunction structure, which boost the light absorption capacity and increase the photogenerated charge separation of g-C 3 N 4. This study provides a reference for the development of efficient carbon based photocatalysts, which can be used not only for the production of H 2 from water splitting, but also for the photodegradation of pollutants under visible light irradiation. [ABSTRACT FROM AUTHOR]

Long linear carbon chains (LLCCs) with sp hybridization are emerging as a promising realization of carbyne, which has been predicted to be a semiconducting nanowire with tunable electronic properties by external stimuli. Here, the LLCCs confined in double-walled carbon nanotubes have been studied by resonant Raman spectroscopy and density functional theory under high pressure. Our results indicate that the band gap linearly decreases from 2.18 to 1.73 eV as pressure increases, which can be explained by the reduction of the bond length alternation of the chains due to the enhanced interaction between the inner tube and the carbon chain. Furthermore, both our experiment and theoretical calculations show that an irreversible pressure-induced interlinkage between inner tubes and carbon chains forms at the system collapse pressure. In our study this value is of 20 GPa, which is determined by the inner tube diameter. These findings provide important insights for tuning the structural and electronic properties of carbon chains, thus may open new perspectives for the realization of nanoscale cables and devices. Image 1024 [ABSTRACT FROM AUTHOR]

We establish a novel carbon phase in purely sp 3 -bonded networks with a 14-atom orthorhombic unit cell, termed C14 carbon, by swarm structural searches. This novel carbon phase is dynamically and mechanically stable under ambient conditions. The C14 carbon exhibits a high bulk modulus of 407 GPa and Vickers hardness of 84.3 GPa, which are comparble to those of diamond. Simulated X-ray diffraction pattern is in satisfactory agreement with the previously unresolved diffraction peaks found in detonation soot samples. Interestingly, electronic band structure calculations reveal that the C14 carbon is a semiconductor with a direct band gap of around 4.60 eV. These results establish a novel carbon phase with outstanding mechanical and electronic properties and offer insights for further exploring other carbon allotropes. Image 10152191 [ABSTRACT FROM AUTHOR]

In the laser cladding process of complex components, laser deflection is a significant issue that greatly affects manufacturing quality. This study investigates the influence of different incident angles on the microstructure and wear resistance of laser-clad layers. Firstly, an Inconel 718 coating was prepared on an Inconel 718 substrate using an IPG fiber laser. Next, the macrostructure and microstructure of the coating were observed using electron microscopy. Finally, the microhardness of the coating was measured, and the underlying mechanisms affecting wear resistance due to incident angle were revealed. The results show that with an increase in the laser incident angle, the laser energy distribution becomes more divergent, leading to a shift in the peak energy density and changes in the macroscopic morphology of the melt pool, exhibiting a non-Gaussian distribution and resulting in increased cellular dendrite count and coarsened grains. Laser deflection causes variations in microstructure and properties between inner and external angles, where higher laser energy density and temperature gradients at the inner angle result in finer grains and more numerous smaller secondary dendrites on the dendritic arms, along with less severe element segregation and higher microhardness at the inner angle. • Distinct microstructural changes were observed in Inconel 718 with varying laser angles. • The coating dilution rate under different laser incidence angles was obtained. • Laser angles significantly impact wear resistance, allowing tailored mechanical properties. [ABSTRACT FROM AUTHOR]

Mechanoluminescent (ML) materials have garnered significant attention due to their capacity for converting mechanical stress into light emission without the need for external power sources. However, very limited efforts have been cast on the response and utilization of water stimulation using ML materials. Herein, we present a highly efficient self-powered luminescent film that exhibits excellent water-responsive properties. The ML intensity of this film shows the zero-quenching performance when exposed to corrosive solutes (acid or saline solution) and within a broad temperature range of 0−100 °C. The ML intensity of the film remains unaffected by long-term water immersion and the impact of water (>1000 times), providing evidence of the durability of this film in humid environments. The COMSOL simulations aim to uncover the dynamic stress distribution of the ML film under two different modes of water stimulation (vibration and deformation). Furthermore, this ML film is used for water speed sensing, and its water speed sensing range is 0.8 m s−1 −6.02 m s−1. Meanwhile, the film's applications have been demonstrated in illumination and display under hydrodynamic force stimulation, human motion recognition, and underwater sensing and communication. The results show that the film can effectively realize the response and visualization to the hydrodynamic force and broaden the application field of mechanoluminescent materials. The water-driven mechanoluminescent film has successfully realized the collection and utilization of water energy and has been successfully applied in water velocity sensing, water-driven lighting, and underwater information communication. [Display omitted] • Robust self-powered mechanoluminescent films for harvesting and direct utilization of water energy. • First self-powered ML peed sensor applicable under harsh environments like high temperature, acid, and saline solution. • Water-driven sensing and underwater communication of the self-powered ML film are demonstrated. [ABSTRACT FROM AUTHOR]

To identify the lithology of coal seam roof and explore the influence of these roofs on the enrichment of coalbed methane, low-frequency rock petrophysics experiments, seismic analyses and gas-bearing trend analyses were performed. The results show that the sound wave propagation speed in rock at seismic frequencies was lower than that at ultrasound frequencies. Additionally, the P-wave velocities of gritstone, fine sandstone, argillaceous siltstone and mudstone were 1,651 m/s, 2,840 m/s, 3,191 m/s and 4,214 m/s, respectively. The surface properties of the coal seam roofs were extracted through 3D seismic wave impedance inversion. The theoretical P-wave impedance was calculated after the tested P-wave velocity was determined. By matching the theoretical P-wave impedance of the four types of rocks with that of the coal seam roofs, we identified the lithology of the roofs. By analyzing known borehole data, we found that the identified lithology was consistent with that revealed by the data. By comparing and analyzing the coal seam roof lithology and the gas-bearing trends in the study area, we discovered that the coal seam roof lithology was related to the enrichment of coalbed methane. In the study area, areas with high gas contents mainly coincided with roof zones composed of mudstone and argillaceous siltstone, and those with low gas contents were mainly associated with fine sandstone roof areas. Thus, highly compact areas of coal seam roof are favorable for the formation and preservation of coalbed methane. [ABSTRACT FROM AUTHOR]

Luminescent hybrid materials based on nanodiamonds (NDs) and rare earth ions have been successfully synthesized by covalently modifying NDs with pyromellitic acid (PMA) which is capable of coordinating to Eu3+ and Tb3+ ions. With NDs acting as a host matrix, the PMA and rare earth ions serve as an organic sensitizer and activator, respectively, yielding a highly bright hybrid composite. Interestingly, for the co-doped hybrid composites ND-PMA-Eu/Tb, the intensity ratio of the two emissions, 5D4→7F5 transition (Tb3+) to 5D0→7F2 transition (Eu3+), is linearly related to temperature in the range from 77 K to 277 K. Therefore, the hybrid could be developed as a self-calibrated ratiometric luminescent thermometer due to its temperature-dependent luminescence performance. [ABSTRACT FROM AUTHOR]

Abstract The level of l -Cysteine (Cys) is an indicator for many diseases of human, thus the selective and sensitive detection of abnormal level of Cys is critically important for human health. In this paper, quenched-carbon dots- Rhodamine B (QCR) system has been developed for the selective and sensitive detection of Cys, where Hg2+-quenched carbon dots (CDs) serve as the reporting unit and the Rhodamine B as the reference unit. The detection limit for the Cys is 52.10 nM, which are much lower than the normal concentration in human urine. Moreover, the sensor shows excellent selectivity for Cys over other amino acids and common cellular ions and environmentally relevant anions. Graphical abstract Image 1 Highlights • A ratiometric fluorescent probe was developed for detection of l -Cysteine. • Rhodamine B and carbon dots are employed as the internal and external report unit. • The built-in correction of the ratiometric design effectively eliminates the errors. • The sensor has low detection limit of 52.10 nM for l -Cysteine. [ABSTRACT FROM AUTHOR]

Abstract Nanodiamonds (NDs) have attracted much attention in biomedical research for their high chemical stability, low toxicity and good biocompatibility. However, the insufficient fluorescence of NDs largely inhibits their multi-functional bio-applications, such as simultaneous diagnosis and chemotherapy. Herein, a multifunctional NDs-based nanoparticles (ND-TTA:RE) with excellent fluorescence and paramagnetic properties has been fabricated by covalently functionalizing NDs with rare-earth (RE = Eu3+, Gd3+) 2-thenoyltrifluoroacetone (TTA) complexes. The NDs-based nanoparticles exhibit intense red emission and could enhance the T 1 -weighted MR image due to the coordinated RE ions. The in vitro / in vivo experiments demonstrate its large potential for optical and MR imaging. In addition, the ND-TTA:RE also shows good drug storage capability that reach to 375 μg/mg towards anticancer drug doxorubicin (Dox) and exhibits significant pH-dependent drug-release behavior. The MTT assays shows that the as-synthesized ND-TTA:RE have low toxicity in a concentration range from 0 to 150 mg/mL, while the Dox-loaded ND-TTA:RE (ND-TTA:RE-Dox) shows effective chemotherapy towards gastric cancer cells. The dual-mode imaging and drug delivery abilities make ND-TTA:RE a promising nanomaterial for multifunctional applications. In addition, this work may also provide a new strategy for the design of multi-functional nanoplatform. Graphical abstract A multi-functional nanoplatform with dual-modal imaging and drug-delivering capabilities has been fabricated by covalently functionalizing nanodiamonds with rare earth complexes. Unlabelled Image Highlights • The NDs were endowed with strong and stable luminescence by covalently binding the rare-earth complex (TTA:RE). • Eu3+ and Gd3+ ions were chelated onto NDs simultaneously to achieve optical/MR dual-modal imaging. • The NDs-based nanoplatform shows high drug storage capabilities, pH-responsive release behavior, and enhanced chemotherapy. [ABSTRACT FROM AUTHOR]

Deep ultraviolet photodetectors have attracted much attention due to their wide applications in the industrial, military, biological and environmental fields. Diamond has a variety of unique characteristics, including a wide bandgap, high thermal conductivity, high breakdown voltage, high carrier mobility, and high radiation hardness, which make it a promising candidate for deep ultraviolet photodetection. With the development of diamond synthesis technology, diamond‐based photodetectors have been extensively studied. This study reviews the recent progress involving various types of diamond‐based photodetectors, including photoconductors, metal–semiconductor–metal photodiodes, Schottky barrier photodiodes, p–n, and p–i–n photodiodes, heterojunctions, and phototransistors. Diamond has a variety of unique optoelectronic characteristics that make it a promising candidate for optoelectronic applications. With the development of diamond synthesis technology, diamond‐based devices are attracting increasing attention from researchers for their excellent properties, particularly their outstanding optoelectronic characteristics. This paper reviews the state‐of‐the‐art research progress in the use of diamonds, with emphasis on its optoelectronic properties, including diamond growth, photodetector fabrication, and applications. [ABSTRACT FROM AUTHOR]

Abstract Development of heterostructured photocatalysts that promotes charge separation of semiconductor materials is crucial towards efficient photocatalytic hydrogen evolution. Here nanodiamond (ND)@graphitic carbon nitride (g-C 3 N 4) nanosheet heterostructures were synthesized via a facile one-step pyrolysis approach. The ND@g-C 3 N 4 heterostructures exhibit enhanced photocatalytic activity for hydrogen evolution from water splitting as compared with pristine g-C 3 N 4. The optimal heterostructures with 10 wt% ND loading content show the best performance in photocatalytic H 2 evolution under visible light irradiation, which is more than 5.6 times higher than that of the pristine g-C 3 N 4. The increased light-trapping induced by the scattering of the NDs promotes more localized charge carriers generation, which is clarified by the combined experimental results and finite difference time domain simulations. Meanwhile, the effective charge separation at the ND@g-C 3 N 4 interface due to the energy level matching can synergistically induce the enhanced photocatalytic activity of g-C 3 N 4. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

ZnO as an eco-friendly material shows bright luminescence under UV illumination when it is tailored into nanoscale size, which makes it a promising luminescent nanomaterial. However, the poor stability of ZnO hinders its applications drastically. In this work, multi-ZnO-cores@uni-BaSO 4 -shell (mZnO@uBaSO 4 ) nanocomposite has been prepared through a non-equilibrium sorption process employing ZnO QDs as the “seeds” and BaSO 4 as the “valve”. The mZnO@uBaSO 4 nanocomposite shows improved photo-, thermal- and ambient-stability compare with bare ZnO QDs. The fluorescence efficiency of the mZnO@uBaSO 4 nanocomposite decreases little even after 60 h of UV irradiation compare with ZnO QDs. The mZnO@uBaSO 4 nanocomposite shows bright luminescence with little decrease even the ambient temperature up to 160 °C and the nanocomposite shows strong resistance to harsh environment. By coating the mZnO@uBaSO 4 nanocomposite and commercial phosphors onto UV-chip, light-emitting diode (LED) with correlated color temperature, Commission Internationale de L'Eclairage coordinate, color rendering index and luminous efficiency of 6109 K, (0.32, 0.33), 85 and 47.33 lm/W have been realized, and this will make a great step towards eco-friendly UV-pumped LEDs. [ABSTRACT FROM AUTHOR]

We investigate the influence of a protective layer on the picosecond laser-induced damage in HfO 2 /SiO 2 high-reflective (HR) coatings. Two types of 1064-nm HR coatings, with and without a SiO 2 protective layer, are deposited using electron beam evaporation. Laser-induced damage tests are operated with 1064-nm, 30-ps laser pulses in one-on-one mode. Five different angles of incidence (AOIs) are considered in the tests for both coatings, in order to modulate the electric field ( E -field) intensity in the HR coatings. The damage morphologies and cross-sections of the damage sites are characterized using scanning electron microscope (SEM) and focused ion beam (FIB), respectively. Experimental results show that the SiO 2 protective layer slightly improves the laser-induced damage threshold (LIDT) of the HR coatings for all AOI values. The damage morphology contains high-density micrometer-scale pits and layer delaminations, at low and high fluences, respectively. The cross-sections of the damage sites and LIDTs for different AOIs are compared with corresponding E -field distributions. For both coatings, the damage is initiated near the peak of the E -field. A negative linear relationship is observed between the LIDT and corresponding maximum E -field intensity for both coatings. [ABSTRACT FROM AUTHOR]

It is still a challenging issue to achieve efficient and tunable fluorescent carbon dot (CD) powders. Herein, we report a novel and general solvothermal strategy to in-situ embedding CDs in trisodium citrate crystal matrix, and these CDs exhibit tunable emission from green to yellow and a high quantum yield up to 21.6% in solid state, comparable to that in solution. This intriguing fluorescence phenomenon may be caused by the space confinement from trisodium citrate crystal matrix, thus enabling CDs to effectively suppress the aggregation-induced luminescence quenching. The CD powders have been employed for fabricating white light-emitting devices on blue chips with adjustable color temperature. Moreover, solid-state lighting systems like flexible fluorescent films and plates have been demonstrated by using the CD powders as the luminescent medium. This work provides a facile way to achieve tunable solid-state fluorescence CD powders, which have promising applications in CDs-based luminescence devices. [ABSTRACT FROM AUTHOR]

Abstract: In contrast to conventional harmonic generation, realized using nonlinear crystal, the multiphoton‐excited (MPE) laser has critical applications in fluorescence imaging probe and biological photonics. Here, lasing emission from a crystal plate under 7‐photon excitation at room temperature is reported for the first time, which is the highest order MPE lasing reported up to date. Moreover, MPE lasing spikes and high‐order harmonic peaks are observed simultaneously. The saturation behavior of harmonic generation and abnormal fluorescence enhancement identify that the interaction of photon–electron in 7‐photon‐excited lasing transits from photon‐excited to a more field‐driven regime. The results may pave the way for short wavelength laser by taking advantage of the processability and larger scale of solid crystals. [ABSTRACT FROM AUTHOR]

Abstract: Single‐crystalline diamond wafers are synthesized, and all‐carbon solar‐blind photodetectors are constructed based on the diamond with interdigitated graphite as electrodes. The graphite electrodes are made by laser‐induced graphitization of the diamond. The peak responsivity of the photodetector is 21.8 A W−1, and detectivity is 1.39 × 1012 cm Hz1/2 W−1 when the bias voltage is 50 V, it is noted that both of these are among the best values ever reported for diamond‐based photodetectors. The photodetectors are employed as the sensing pixels in an imaging system, and a clear image is obtained, which is the first report on solar‐blind imaging of diamond photodetectors. The results reported in this paper provide a facile approach to high‐performance diamond solar‐blind photodetectors and their applications in solar‐blind imaging, thus may address a significant step toward the preparation and application of diamond photodetectors. [ABSTRACT FROM AUTHOR]

Synthetic diamonds have inspired much interest for their unique photophysical properties and versatile potential applications, but their phosphorescent phenomenon and mechanism have been paid much less attention. Here, phosphorescent diamonds with a lifetime of 5.4 s were synthesized by high-pressure and high-temperature method, and the diamonds exhibit an emission band at around 468 nm under the excitation wavelength of 230 nm. The quantum yield of the phosphorescent diamonds is about 4.7% at ambient temperature and atmosphere, which is the first report on the quantum yield of diamonds. The unique phosphorescence emission can be attributed to the radiative recombination from iron related donors and boron related acceptors. [ABSTRACT FROM AUTHOR]

Luminescent hybrid materials were prepared by covalently functionalizing nanodiamonds (NDs) with rare earth (RE) complexes. Pyromellitic acid (PMA), as the organic sensitizer, was grafted onto amino-terminated NDs to chelate lanthanide ions (Eu 3+ and Tb 3+ ). The emission colors of the hybrid composite of ND-PMA-Eu x Tb y can be tuned from red to orange, yellow and green by adjusting the molar ratio of Eu 3+ to Tb 3+ . Moreover, the luminescence of the hybrid composites exhibits remarkable photostability under ultraviolet irradiation for 60 h. As a proof-of-concept experiment, the as-synthesized ND-PMA-Eu and ND-PMA-Tb were employed as the phosphors for red and green light-emitting-diode (LED) devices with ultraviolet (UV) chips. Therefore, the nanodiamond-based luminescent hybrid material may find potential application in optical device. [ABSTRACT FROM AUTHOR]

Control of aggregation plays an important role in the photophysical behavior of luminescent nanomaterials. Herein, the concentration-dependent self-assembled hybrid of carbon nanodots (CDs) with the alteration spectral characters of H-/J-aggregation were observed. In detail, the CDs aging under different conditions presented obvious spectral variations ranging from visible to near-infrared regions, accompanied by the spontaneous evolution of nanoaggregates from CD nanoparticles. Theoretical calculations and experimental results confirmed the inhomogeneous surface functional groups could render CDs into nanoaggregates with the H- or J-aggregation through intraparticle or interparticle interaction, inducing the discrepant surface-confined charges in these intraparticle nanoaggregates and further contributing to their shift of absorption and emission bands. With the novel aggregation regulation, the CDs exhibited a tunable increase in their photothermal and photodynamic capability in comparison to their original counterparts. These findings shed a new light on the understanding of the photophysical behaviors for the self-assembled hybrid of CDs with the concept of supramolecular engineering. Aggregation plays an important role in the photophysical behavior of luminescent nanomaterials. Herein, the concentration-dependent self-assembled hybrid of carbon nanodots (CDs) with the alteration spectral characters of H-/J-aggregation was observed. Theoretical calculations and experimental results confirmed the inhomogeneous surface functional groups could render CDs into nanoaggregates with different aggregation states such as H- and J-aggregation through intraparticle or interparticle interaction, inducing the discrepant surface-confined charges in these intraparticle nanoaggregates and further contributing to their shift of absorption and emission bands. This work presents a novel concept of supramolecular engineering in CDs, which can be used to understand the luminescence mechanism and simultaneously regulate the photophysical properties of CDs. [Display omitted] [ABSTRACT FROM AUTHOR]

Four phenylfuropyridone racemates, (±)-tersones A-C and E (1−3, 5), one phenylpyridone racemate, (±)-tersone D (4), one new pyridine alkaloid, tersone F (6), single new phenylfuropyridone, tersone G (7) and two known analogs 8 and 9 were isolated from the deep-sea fungus Phomopsis tersa. Their structures and absolute configurations were characterized on the basis of comprehensive spectroscopic analyses, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) calculations. Moreover, compounds 1−9 were evaluated for in vitro antimicrobial and cytotoxic activity. Compounds 5b and 8b exhibited antibacterial activity against S. aureus with the MIC value of 31.5 μg/mL, while compound 5b showed cytoxic activities against SF-268, MCF-7, HepG-2 and A549 cell lines with IC50 values of 32.0, 29.5, 39.5 and 33.2 μM, respectively.

Ultraviolet (UV) femtosecond lasers with a high repetition rate have important applications, especially in processing brittle materials. However, the group velocity walk-off limits the tripling efficiency of the 1 μ m femtosecond pulse. Without effective compensation, the tripling efficiency was generally less than 1%. In this study, by optimizing a birefringent BBO crystal to compensate the temporal walk-off in the 1. 03 μ m tripling process, a maximum output power of 1.9 W with a repetition rate of 145 kHz at 344 nm was obtained, which implied a conversion efficiency of 30.5% from infrared (IR) to UV. The generated UV laser showed good power stability of 0.19% rms over 1 h and beam quality of M 2 < 1.2. Using this scheme for other IR femtosecond lasers is promising for achieving high tripling efficiency. [ABSTRACT FROM AUTHOR]

• The CDs integrated NIR-II absorption (1033 nm) and NIR-I emission (670 nm). • D- π -A charge-transfer state yields the NIR-II absorption. • Localized excited state from large conjugated sp2 domain leads to NIR-I emission. • Multiphoton bioimaging and cancer photothermal therapy were realized with the CDs. Carbon dots (CDs) with absorption and emission properties in near-infrared (NIR) bio-windows highlight their application in the integration of diagnosis and treatment. In this work, CDs with NIR-I emission and NIR-II absorption have been demonstrated, by constructing localized excited state and charge-transfer state. NIR fluorescence together with photothermal effect was observed in the CDs under NIR light illumination. The electron donors (D) and acceptors (A) groups around the carbon core of the CDs lead to D- π -A charge-transfer state, producing a strong electronic push–pull effect and yielding the desired NIR-II absorption with a maximum absorption peak at 1033 nm. Localized excited state from large conjugated rigid sp2 domain leads to NIR-I emission of 670 nm. Multiphoton-induced NIR-I emission (quantum yield is 29%) and NIR-II induced heat with photothermal conversion efficiency of 41.19% have been realized. In addition, multiphoton cellular imaging and cancer photothermal therapy using the CDs as imaging and photothermal agents have been demonstrated. The results provide a route to CDs with NIR absorption/emission characters and prospect their potential application in multiple-photon bioimaging and photothermal therapy of cancers. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles (NPs) have been synthesized by a facile one-step synthesis method, and the emission color of the ZnO NPs can be tuned from orange to yellow, green, blue-green and blue. These ZnO NPs were used as phosphors to fabricate UV-pumped white light-emitting diodes (WLEDs). The color rendering index of the WLEDs is (0.31, 0.33), which is close to the standard white emission. The WLEDs have high correlated color temperature (6532 K) and Commission International de L'Eclairage (90.4). These results indicated that the multi-colored ZnO NPs have great application potential in lighting and display. • A facile one-step method was developed for the preparation of multi-colored ZnO NPs, and the emission color of the NPs can be tuned from orange to yellow, green, blue-green and blue. • The fluorescence emission of these NPs transitioned from orange to blue by adjusting their particle size from 10 nm to 4 nm, which was due to quantum confinement effect. • Based on their unique optical properties, multi-colored ZnO NPs were used to prepare the WLEDs. The CIE of the WLEDs was (0.31, 0.33), which was close to the standard white emission. In addition, the WLEDs had a high CCT (6532 K) and CIR (90.4). [ABSTRACT FROM AUTHOR]

[Display omitted] • Water-soluble ZnO NPs are developed to control the soybean spoilage during soaking process. • ZnO NPs inhibit the microbial growth and alleviate the decrease of pH and firmness. • ZnO NPs effectively inactivate three spoilage bacteria isolated from the deteriorated soybeans. • ZnO NPs exhibit superior antibacterial effects compared with two commercial ZnO NPs. • The Zn content in ZnO NPs-treated soybeans was below the tolerance limit in soybean products. The microbial spoilage of soybeans during soaking process severely deteriorates the quality of soybean products and threatens human health. Herein, water-soluble aminated zinc oxide nanoparticles (ZnO NPs) were developed to effectively control the microbial spoilage in soybeans during soaking. ZnO NPs achieved significant inactivation of three dominant spoilage bacteria (bacillus cereus , bacillus megaterium and enterococcus faecium) isolated from the deteriorated soybeans, which could adhere to the bacterial surface and damage the cell wall/membrane, but also generate large amounts of reactive oxygen species (ROS). Compared to two commercial ZnO, water-soluble ZnO exhibited superior antibacterial properties due to producing more ROS and bacteria-adhered ability. After ZnO NPs treatment, the content of the residual Zn (51.1 mg/kg) in soybeans was the safety standards of Zn element in soybeans products for human). Therefore, the water-soluble ZnO NPs showed great potentials as efficient and safe antimicrobial agents for soybeans preservation during soaking process. [ABSTRACT FROM AUTHOR]

Although nitrogen-doped zinc oxide has been fabricated as a light-emitting diode, the origin of its p-type conductivity remains mysterious. Here, by analyzing the surface reaction pathway of N in ZnO with first-principles density functional theory calculations, we demonstrate that the origin of p-type conductivity of N-doped ZnO can originate from the defect complexes of NZn-VO and NO-VZn. Favored by the Zn-polar growth, the shallow acceptor of N0-VZn actually evolves from the double-donor state of NZn-VO- While NO-VZn is metastable, the p-doping mechanism of NZn-VO → NO-VZn in ZnO will be free from the spontaneous compensation from the intrinsic donors. The results may offer clearer strategies for doping ZnO p-type more efficiently with N. [ABSTRACT FROM AUTHOR]

Abstract: Mg x Zn1−x O alloy films were prepared on sapphire substrates using Ar and N2 as the sputtering gases. The effect of the sputtering gas on the structural, optical and electrical properties of the Mg x Zn1−x O films was studied. By using N2 as the sputtering gas, the Mg x Zn1−x O film shows p-type conductivity and the band gap is larger than that employing Ar as the sputtering gas. The reason for this phenomenon is thought to be related to the reaction between N–O or N–Zn, and the N-doping. [Copyright &y& Elsevier]

[Display omitted] • EM absorption ability of N-doped CDs has been investigated for the first time. • CDs present superior EM minimum reflection loss of −26.5 dB and maximum bandwidth of 4.85 GHz. • Controllable nitrogen doping in CDs regulates the impedance matching and dielectric loss. The development of electromagnetic (EM) microwave absorption materials is essential for the whole electrical and electronic systems. Although carbon-based materials have been widely studied as EM absorber, the problems such as high cost, complicated processing technology and insufficient shielding performance still remain unsettled. Here, carbon nanodots (CDs) prepared through a one-step microwave-assisted heating method are demonstrated as EM absorption materials for the first time. With regulation of the doped nitrogen contents and degree of graphitization, the minimum EM reflection loss of the CDs at 10.7 GHz is −26.5 dB, and the effective absorption bandwidth of 1.5-mm thickness is 4.85 GHz. By adjusting the thickness, the effective absorption band ranges from 3.3 to 18 GHz, which is better than most non-composite carbon materials. The superior performance can be attributed to the excellent impedance matching and high dielectric loss in CDs. These results may extend the application fields of CDs and offer new insight into the exploitation of effective carbon-based EM shielding materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synthetic routes and functionalization of nanodiamonds (NDs) were introduced. • The recent progress of NDs in nanomedical applications, including bioimaging, drug delivery and biosensing, was summarized. • The outlook towards the future developments and applications of NDs was provided. Nanodiamonds (NDs) have excellent mechanical and optical properties, large surface area, easy bioconjugation and high biocompatibility, which makes them especially appealing for various potential applications. In recent years, NDs have received considerable attention in nanomedicine, and some noteworthy progress has been achieved. This review summarizes the synthetic routes and unique properties of NDs. In addition, the recent progress of NDs in nanomedical applications, including bioimaging, drug delivery and biosensing, is also discussed. We further provide an outlook towards the future developments and applications of NDs. [ABSTRACT FROM AUTHOR]

A ratiometric fluorescence sensor based on europium-grafted ZnO quantum dots for the detection of tetracycline was developed and the sensor exhibited high sensitivity. [Display omitted] • A ratiometric fluorescence sensor based on europium-grafted ZnO quantum dots for the detection of tetracycline was developed. • The nanoprobe shows high sensitivity and has good selectivity. • Visual and quantitative real-time detection of TC was realized. An europium functionalized ZnO quantum dots (QDs) ratiometric fluorescent nanoprobe is designed to establish a real time, on-site visual, and highly sensitive probe method for tetracycline (TC). The yellow-emitting ZnO QDs serves as the internal reference, while the Eu3+ chelated on the surface of ZnO QDs is used as the signal reporting unit. This nanoprobe exhibits rapid response, excellent selectivity, and high sensitivity with a detection limit of 4 nM in detecting the levels of TC. In addition, fluorescence of the nanoprobe can change from yellow to red as the concentration of TC increases. Thus, naked eye detection of TC was realized using the test paper processed by nanoprobe, followed by RGB value analysis function on the mobile phone APP. [ABSTRACT FROM AUTHOR]

A multifunctional nanocomposite (UCMP-NDs) was constructed by combining NaGdF 4 :Yb,Er upconversion magnetic nanoparticles (UCMPs) and nanodiamonds (NDs) for dual-mode imaging and drug delivery. In this nanocomposite, nanodiamonds are used as drug carrier, and NaGdF 4 :Yb,Er nanoparticles act as dual-modal imaging agents for upconversion fluorescence and magnetic resonance imaging (MRI). When irradiated by 980 nm near-infrared light, the UCMP-NDs uptaken by cells show green emission, indicating its promising potential for fluorescence imaging. T 1 -weighted MRI of the nanocomposite in aqueous solutions reveals that the contrast brightening increases with the concentration of Gd3+ component. In addition, the anticancer drug doxorubicin (Dox) can be absorbed onto the nanocomposites and released in a pH-sensitive pattern. The nanocomposites show low systematic toxicity and high antitumor therapeutic efficacy. In vitro cell cytotoxicity tests on cancer cells verify that the Dox-loaded UCMP-NDs have comparable cytotoxicity with free Dox at the same of Dox concentration. Therefore, the developed multifunctional nanocomposites provide promising applications in oncotherapy by integrating cancer diagnosis and collaborative therapy. We fabricated a nanocomposite (UCMP-NDs) by conjugating NaGdF 4 magnetic nanoparticles (MPs) with NDs through amidation reaction for fluorescent imaging, MRI, and drug-delivering contemporaneously. [Display omitted] • we fabricated a nanocomposite (UCMP-NDs) for fluorescent imaging, MRI, and drug-delivering simultaneously. • UCMP-NDs nanocomposite worked as upconversion fluorescence and T 1 -weighted magnetic resonance imaging agent. • The doxorubicin-loaded UCMP-NDs had preferable killing effect against Hela cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • CL quenching is observed due to water-induced aggregation and energy transfer. • Surface chemical engineering is first attempted to improve CL performance of CDs. • CDs modified by n-butylamine exhibit a CL performance outperforming the commercial dyes. Carbon nanodots (CDs) are emerging as low toxic chemiluminescent (CL) materials for new-generation cold lighting and bioimaging technology due to their tunable and efficient emissions. Nevertheless, continuous progress and efforts are still needed to improve the luminance and lifetime of the CL CDs. Here, CL quenching is observed in the CD-peroxyoxalate-hydrogen peroxide system, resulting from the water-induced aggregation and blocking effect of the electron exchange between the CDs and energetic intermediate produced in the CL reaction. A surface chemical regulation strategy is first introduced to improve the CL performance of CDs. Optimized the capped ligand species and chain length, the CDs modified by n-butylamine exhibit a CL quantum yield of 1.15 × 10–2 einsteins mol−1 and maximal luminance of 5.11 cd m−2, which is about 5- and 13-fold higher than the initial CDs and comparable with commercially available Rhodamine B. The enhanced performance can be explained by the decreased electron capture from water molecules generated due to the decomposition of hydrogen peroxide in the CL process. [ABSTRACT FROM AUTHOR]

Poor stability as an essential issue of metal halide perovskites (MHPs), limits their further applications in displaying and lighting. Among multicolor luminous MHPs, the development of blue luminous perovskite lags far behind that of red and green emission. Herein, a "MAPbBr x Cl 3-x quantum dots (QDs) in Pb(OH)Br" strategy is proposed, fabricating stable MAPbBr x Cl 3-x @Pb(OH)Br with the emission wavelength of 435–485 nm. Experimental characterizations indicate that cubic MAPbBr x Cl 3-x transforms into rectangular MAPbBr x Cl 3-x @Pb(OH)Br with the assistance of methylamine vapor. The as-prepared MAPbBr x Cl 3-x @Pb(OH)Br shows high stability of water, light, heat and organic solvents, which can emit bright emission even they are immersed in water for 6 months. In addition, anion exchange induced spectral shift of the MHPs are also suppressed due to the chemical inertness of Pb(OH)Br. Notably, this strategy is also applied to all inorganic halide perovskites. Blue light-emitting devices (LEDs) based on the MAPbBr x Cl 3-x @Pb(OH)Br have been demonstrated, which can run stably for over 8 h with brightness exceeding 1000 cd/m2 in a humid environment. • A "MAPbBr x Cl 3-x quantum dots in Pb(OH)Br" strategy has been proposed to fabricate stable blue MAPbBr x Cl 3-x @Pb(OH)Br. • The prepared samples have excellent water, organic solvent, thermal and light stability. • Blue light-emitting devices (LEDs) based on the samples can run continuously for 8 h in a humid environment. [ABSTRACT FROM AUTHOR]

Mechanoluminescent materials that could convert mechanical energy into light energy have attracted increasing attention in recent years for their wide potential applications in stress sensing and imaging, structural damage monitoring, wearable illuminating devices, self-powered display, mechanical energy collection and conversion. However, their relatively low mechanoluminescence intensity greatly hinders the practical application. Here, we present a simple and effective strategy to enhance the mechanoluminescence performance of ZnS:Mn phosphor by Li ion co-doping. ZnS:Mn,Li phosphors of the hexagonal wurtzite structure have been prepared via high temperature solid phase sintering. The PL and ML intensity have been enhanced by 338% and 610% for samples obtained when 4 and 5 at. % Li is introduced in the precursor materials, respectively, in comparison with those without Li dopant. The photoluminescence lifetime of ZnS:Mn,Li decreases gradually, indicating the enhanced non-radiative energy transfer as the Li concentration increases. The electron paramagnetic resonance spectroscopy is carried out to investigate the changing tendency of the sulfur vacancy of samples with various Li-doping concentration. The mechanism for mechanoluminescence enhancement is supposed to be correlated with the increased sulfur vacancies by Li co-doping, which may facilitates the non-radiative energy transfer and thereby improve the luminescence properties of the samples. These findings provide a feasible strategy to enhance the mechanoluminescence performance of traditional ZnS derived phosphors, and may contribute to developing novel mechanoluminescence materials for practical applications. • A simple strategy to enhance the mechanoluminescence output of ZnS:Mn by up to 610%. • The fluorescence lifetime decreases with the increase in precursor Li concentration. • The mechanism is attributed to the increased sulfur vacancy by Li-ion co-doping. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL) induced by peroxalate fuel and hydrogen peroxide has been widely applied in chemical detection and bioimaging. Nevertheless, the chemiluminescent emitters in the CL are focused on organic small-molecular dyes, most of which encounter serious obstacles in practical application due to their potential biotoxicity and low photostability. Here, bright blue CL is observed when biocompatible zinc oxide nanoparticles (ZnO NPs) with yellow photoluminescence (PL) are added into peroxalate and hydrogen peroxide solution, which is originated from the interaction between the zinc interstitial of ZnO NPs and the energy-rich intermediate produced in the CL process. With the modification of silane coupler, the CL quantum yield of ZnO NPs presents two orders of magnitude increase from 6.2× 10−6 to record 3.7 × 10−4 E⋅mol−1 for inorganic NPs owing to the protective effect from silicon oxide shell layer. By virtual of excellent CL ability, ZnO NPs have been firstly used as CL probes in bioimaging, which opens the way to a new design freedom for biosensor or bioimaging in the future. • Chemiluminiscence quantum yield of ZnO NPs with silane shell presents two orders of magnitude increase. • ZnO NPs with silane shell show the highest chemiluminiscence quantum yield value for the inorganic NPs. • ZnO NPs have been served as CL probes in bioimaging for the first time. • The chemiluminiscence of ZnO NPs has been clarified through the chemically initiated electron exchange. • The excitation electron of ZnO can transit from the zinc interstitial atom energy level to valence band and emit blue light. [ABSTRACT FROM AUTHOR]

• Low-coherent pulse with precise temporal shaping and spectral control. • μJ-level instantaneous broadband pulse of time-spectrum independent. • Coherence time is 123 fs, much shorter than pulse duration. • Output instability less than 1% rms and 8% peak-to-valley over 4 h. A μJ-level low-coherent pulse with dynamic and precise temporal shaping and spectral control is demonstrated. Low-coherent light delivered by a superluminescent diode is precisely shaped through a wave guide amplitude modulator driven by an arbitrary waveform generator. Utilizing a three-stage axial-alternating polarization-maintaining single-mode fiber amplifier, μJ-level low-coherent pulses with 3 ns durations and 20 nm instantaneous bandwidths at a 1 kHz repetition rate are obtained. In addition, a spectral control unit is used to adjust the spectrum shape. As a result, near flat-top, saddle-type, or other required special spectra can be produced. The low temporal coherence characteristics and output stability are characterized experimentally. [ABSTRACT FROM AUTHOR]

Although Mn-doped lead halide perovskites could alleviate the environmental burden of Pb, their synthesis process suffers from intricate operations, high operating temperature, low production, or toxic strong polar solvents. Developing a simple and green route for Mn-doped halide perovskites with mass production is highly desirable for perovskite-derived applications. In this work, we developed a facile and environmental-benign synthesis strategy for large-scale preparation of Mn-doped lead halide perovskite nanocrystals. The nanocrystals were prepared via a mechano-synthesis process without organic solvents. We investigated the influence of atomic composition on their morphology, crystal structure and optical performance. Our results show that the perovskite nanocrystals have dual-emissions from the 4T 1 to 6A 1 transition of Mn2+ and the excitonic recombination of perovskite hosts, respectively. The achieved Mn:CsPbX 3 nanocrystals show well-tailored color rendering when used as LED phosphors. This work presents a scalable and facile strategy for Mn-doped perovskite production without organic solvents, which promises low-cost and eco-friendly LEDs. Image 1 • We presented a universal strategy for large-scale and solvent-free production of Mn-doped perovskite nanocrystals. • The proposed mechano-synthesis process may greatly alleviate environmental burden from organic solvents. • The achieved Mn:CsPbX3 nanocrystals have well-tailored color rendering and show great potential in high performance LEDs. [ABSTRACT FROM AUTHOR]

Red/near‐infrared (NIR) emissive carbon nanodots (CNDs) with photoluminescence (PL) quantum yield (QY) of 57% are prepared via an in situ solvent‐free carbonization strategy for the first time. 1‐Photon and 2‐photon cellular imaging is demonstrated by using the CNDs as red/NIR fluorescence agent due to the high PL QY and low biotoxicity. Further study shows that the red/NIR CNDs exhibit multiphoton excited (MPE) upconversion fluorescence under excitation of 800–2000 nm, which involves three NIR windows (NIR‐I, 650–950 nm; NIR‐II, 1100–1350; NIR‐III, 1600–1870 nm). 2‐Photon, 3‐photon, and 4‐photon excited fluorescence of the CNDs under excitation of different wavelengths is achieved. This study develops an in situ solvent‐free carbonization method for efficient red/NIR emissive CNDs with MPE upconversion fluorescence, which may push forward the application of the CNDs in bioimaging. [ABSTRACT FROM AUTHOR]

The various luminescent properties of carbon nanodots (CDs) reveal fascinating applications in several areas. Here, bright and multicolor chemiluminescence (CL) is realized from CDs, whose CL quantum yield can be optimized by adjusting the energy level alignment between the CDs and 1,2‐dioxetanedione intermediate generated from the reaction of peroxalate and hydrogen peroxide. A CL quantum yield of 9.32 × 10−3 Einsteins mol−1, maximal luminance of 3.28 cd m−2, and lifetime of 186.4 s are achieved in red CDs, all of which are the best values ever reported for CDs. As a proof‐of‐concept prototype, a high‐quality information encryption strategy is established via CD based CL imaging techniques by virtue of the high brightness and multicolor CL. [ABSTRACT FROM AUTHOR]

Plasmonic lasers, which make use of the strong confinement of surface plasmon polaritons (SPPs), are key components to realize ultracompact coherent light sources at deep subwavelength scale. Currently, large metal and radiation losses of their metallic cavities limit electrically driven plasmonic lasers operation mainly at cryogenic temperature, where sufficient gain can be obtained. It is a crucial challenge to accomplish high performance electrically driven plasmonic lasers operated at room temperature. Benefiting from the large exciton binding energy and large oscillator strength of zinc oxide (ZnO) gain media, an optically pumped ultraviolet (UV) plasmonic laser is demonstrated from a hybrid metal–insulator–semiconductor structure, in which a magnesium oxide (MgO) gap layer plays a critical role in reducing the metallic loss. Further optimizing the thickness of the MgO gap layer and ZnO active layer, room temperature electrically driven UV plasmonic lasers with a threshold of 70.2 A cm‐2 are realized for the first time under the injection of electrical carriers through the metallic electrode of the hybrid structure. Localizing light in subwavelength dimension, this novel type of UV plasmonic nanolasers may find various applications in photolithography, sensing, integrated microfluidic systems for surface sterilizations and nanoscale treatment processes. [ABSTRACT FROM AUTHOR]

In classical photodynamic therapy, tumor cells are killed by the cytotoxic species via type-I/II photochemical reactions, seriously limited by the external photoexcitation and hypoxia. Herein, the electron transfer mechanism between fluorophores and peroxalate-H 2 O 2 reaction is investigated and the singlet/triplet electron exchange is utilized to achieve long-persistent chemiluminescence imaging and synergistic type-I/II/III photodynamic therapy. As a proof-of-concept, the photosensitizers of carbon nanodots (CDs)-loaded chlorin e6 (CDs-Ce6) are designed and integrated with the peroxalate molecules, and the as-prepare polymer carbon nanodots (p-CDs) exhibit novel tumor microenvironment (TME)-responsive long-persistent near-infrared CL and photochemical reactions, evoking the in vivo imaging and synergistic dynamic therapy in tumor tissue. Mechanistically, the excess reactive oxygen species in TME can trigger the chemically initiated singlet/triplet electron exchange between the hydrophobic CDs-Ce6 and peroxalate-derived 1,2-dioxetanes and thus the excess excited singlet/triplet electron of the CDs-Ce6 can ensure the long-persistent near-infrared CL, type I/II photochemical production of hydroxyl radicals, superoxide radical and singlet oxygen, and type III photochemical damage of maladjusted biomacromolecules, enabling the long-persistent near-infrared biological imaging and enhanced cancer therapy. These results shed a new sight into the energy transfer mechanism in chemiluminescence and pave a new sight into the architecture of multifunctional theragnostic nanoplatforms., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Mechanoluminescence (ML)-based sensors are emerging as promising wearable devices, attracting attention for their self-powered visualization of mechanical stimuli. However, challenges such as weak brightness, high activation threshold, and intermittent signal output have hindered their development. Here, a mechanoluminescent/electric dual-mode strain sensor is presented that offers enhanced ML sensing and reliable electrical sensing simultaneously. The strain sensor is fabricated via an optimized dip-coating method, featuring a sandwich structure with a single-walled carbon nanotube (SWNT) interlayer and two polydimethylsiloxane (PDMS)/ZnS:Cu luminescence layers. The integral mechanical reinforcement framework provided by the SWNT interlayer improves the ML intensity of the SWNT/PDMS/ZnS:Cu composite film. Compared to conventional nanoparticle fillers, the ML intensity is enhanced nearly tenfold with a trace amount of SWNT (only 0.01 wt.%). In addition, the excellent electrical conductivity of SWNT forms a conductive network, ensuring continuous and stable electrical sensing. These strain sensors enable comprehensive and precise monitoring of human behavior through both electrical (relative resistance change) and optical (ML intensity) methods, paving the way for the development of advanced visual sensing and smart wearable electronics in the future., (© 2024 Wiley‐VCH GmbH.)

Phosphorescence in carbon dots (CDs) from triplet exciton radiative recombination at room temperature has achieved significant advancement. Confinement and nanoconfinement, serving as valuable techniques, are commonly utilized to brighten triplet exciton in CDs, thereby enhancing their phosphorescence. However, a comprehensive and universally applicable physical description of confinement-enhanced phosphorescence is still lacking, despite efforts to understand its underlying nature. In this study, the dominance of entropy is revealed in triplet exciton emission from CDs through the establishment of a microscopic vibration state model. CDs with varying entropy levels are studied, indicating that in a low entropy system, the multi-energy triplet exciton emission in CDs exhibits enhanced brightness, accompanied by a corresponding increase in their lifetimes. The product of lifetime and intensity in CDs serves as a descriptor for their phosphorescence properties. Moreover, an entropy-dependent information variation system based on the CDs is demonstrated. Specifically, in a low-entropy system, information is retained, whereas the corresponding information is erased in a high-entropy system. This work elucidates the underlying physical nature of confinement-enhanced triplet exciton emission, offering a deeper understanding of achieving ultralong phosphorescence in the future., (© 2024 Wiley‐VCH GmbH.)

Room-temperature phosphorescent materials, renowned for their long luminescence lifetimes, have garnered significant attention in the field of optical materials. However, the challenges posed by thermally induced quenching have significantly hindered the advancement of luminescence efficiency and stability. In this study, thermally enhanced phosphorescent carbon nanodots (CND) are developed by incorporating them into fiber matrices. Remarkably, the phosphorescence lifetime of the thermally enhanced CND exhibits a twofold enhancement, increasing from 326 to 753 ms, while the phosphorescence intensity experienced a tenfold enhancement, increasing from 25 to 245 as the temperature increased to 373 K. Rigid fiber matrices can effectively suppress the non-radiative transition rate of triplet excitons, while high temperatures can desorb oxygen adsorbed on the surface of the CND, disrupting the interaction between the CND and oxygen. Consequently, a thermally enhanced phosphorescence is obtained. In addition, benefiting from the thermally enhanced phosphorescence property of CND, a warning indicator with an anti-counterfeiting function for monitoring cold-chain logistics is demonstrated based on CND., (© 2024 Wiley‐VCH GmbH.)

Physical unclonable functions (PUFs) have emerged as an unprecedented solution for modern information security and anticounterfeiting by virtue of their inherent unclonable nature derived from distinctive, randomly generated physical patterns that defy replication. However, the creation of traceable optical PUF tags remains a formidable challenge. Here, we demonstrate a traceable PUF system whose unclonability arises from the random distribution of diamonds and the random intensity of the narrow emission from germanium vacancies (GeV) within the diamonds. Tamper-resistant PUF labels can be manufactured on diverse and intricate structural surfaces by blending diamond particles into polydimethylsiloxane (PDMS) and strategically depositing them onto the surface of objects. The resulting PUF codes exhibit essentially perfect uniformity, uniqueness, reproducibility, and substantial encoding capacity, making them applicable as a private key to fulfill the customization demands of circulating commodities. Through integration of a digitized "challenge-response" protocol, a traceable and highly secure PUF system can be established, which is seamlessly compatible with contemporary digital information technology. Thus, the GeV-PUF system holds significant promise for applications in data security and blockchain anticounterfeiting, providing robust and adaptive solutions to address the dynamic demands of these domains.

In this Letter, we use quantum trajectory theory to simulate heterodyne detection of narrow bandwidth superradiant lasing from an incoherently excited atomic ensemble. To this end, we describe the system dynamics and account for stochastic measurement backaction by second-order mean-field theory. Our simulations show how heterodyne measurements break the phase symmetry, and initiate the atomic coherence with a random phase and a long temporal phase coherence. More importantly, our theory allows direct simulation of experimental procedures for extraction of spectral information which do not lend themselves to evaluation with the quantum regression theorem.

Due to the broadband response and low selectivity of external light, negative photoconductivity (NPC) effect holds great potential applications in photoelectric devices. Herein, different photoresponsive carbon nanodots (CDs) are prepared from diverse precursors and the broadband response from the NPC CDs are utilized to achieve the optoelectronic logic gates and optical imaging for the first time. In detail, the mcu-CDs which are prepared by the microwave-assisted polymerization of citric acid and urea possess the large specific surface area and abundant hydrophilic groups as sites for the adsorption of H 2 O molecules and thereby present a high conductivity in dark. Meanwhile, the low affinity of mcu-CDs to H 2 O molecules permits the light-induced desorption of H 2 O molecules by heat effect and thus endow the mcu-CDs with a low conductivity under illumination. The easy absorption and desorption of H 2 O molecules contribute to the extraordinary NPC of mcu-CDs. With the broadband NPC response in CDs, the optoelectronic logic gates and flexible optical imaging system are established, achieving the applications of "NOR" or "NAND" logic operations and high-quality optical images. These findings unveil the unique optoelectronic properties of CDs, and have the potential to advance the applications of CDs in optoelectronic devices., (© 2024 Wiley‐VCH GmbH.)

The growth of fused silica surface damage poses a high risk in operating high-power laser devices, with complex physical mechanisms related not only to the wavelength, pulse width, fluence of incident pulse lasers, but also to initial damage size and material properties. With low-temporal coherence light (LTCL) increasingly applied in high-power laser-driven inertial confinement fusion (ICF), LTCL-induced damage growth has become a bottleneck limiting output power improvements. This paper analyzes LTCL damage growth characteristics and mechanisms on fused silica surfaces, obtaining its damage growth coefficient and threshold. By analyzing chemical composition variation, electric field of initial damage, and comparing the damage growth threshold of artificial initial damage, the mechanism of surface damage growth is investigated. This research provides reliable information for estimating fused silica lifetime in high-power LTCL devices and contributes to understanding LTCL properties.