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The relatively large ionic radius of the Na ion is one of the primary reasons for the slow diffusion of Na ions compared to that of Li ions in de/intercalation processes in sodium-ion batteries (SIBs). Interlayer expansion of intercalation hosts is one of the effective techniques for facilitating Na-ion diffusion. For most ionic layered compounds, interlayer expansion relies on intercalation of guest ions. It is important to investigate the role of these ions for material development of SIBs. In this study, alkali-metal ions (Li+, Na+, K+, and Cs+) with different sizes were intercalated into lepidocrocite-type layered titanate by a simple ion-exchange technique to achieve interlayer modulation and those were then evaluated as anode materials for SIBs. By controlling the intercalated alkaline ion species, basal spacings of layered titanates (LTs) in the range of 0.68 to 0.85 nm were obtained. Interestingly, the largest interlayer spacing induced by the large size of Cs did not yield the best performance, while the Na intercalated layered titanate (Na-ILT) demonstrated a superior performance with a specific capacity of 153 mAh g-1 at a current density of 0.1 A g-1. We found that the phenomena can be explained by the high alkaline metal ion concentration and the efficient utilization of the active sites in Na-ILT. The detailed analysis indicates that large intercalating ions like Cs can hamper sodium-ion diffusion although the interlayer spacing is large. Our work suggests that adopting an appropriate interlayer ion species is key to developing highly efficient layered electrode materials for SIBs.

Ultraviolet (UV) visualization has extensive applications in military and civil fields such as security monitoring, space communication, and wearable equipment for health monitoring in the internet of things (IoT). Due to their remarkable optoelectronic features, perovskite materials are regarded as promising candidates for UV light detecting and imaging. Herein, we report for the first time the excitation-dependent perovskite/polymer films with dynamically tunable fluorescence ranging from green to magenta by changing the UV excitation from 260 to 380 nm. And they still render dynamic multi-color UV light imaging with different polymer matrixes, halogen ratios, and cations of perovskite materials. The mechanism of its fluorescence change is related to the chloride vacancies in perovskite materials. A patterned multi-color ultraviolet visualization pad is also demonstrated for visible conversion of the UV region. This technique may provide a universal strategy for information securities, UV visualizations, and dynamic multi-color displays in the IoT.

Acknowledgements: This work was supported by the National Natural Science Foundation of China (Grant Nos. 62075198, 11974317, 12274378), Outstanding Youth Foundation of Henan (Grant Nos. 222300420087)., Multiphoton excited luminescence is of paramount importance in the field of optical detection and biological photonics. Self-trapped exciton (STE) emission with self-absorption-free advantages provide a choice for multiphoton excited luminescence. Herein, multiphoton excited singlet/triplet mixed STE emission with a large full width at half-maximum (617 meV) and Stokes shift (1.29 eV) has been demonstrated in single-crystalline ZnO nanocrystals. Temperature dependent steady state, transient state and time-resolved electron spin resonance spectra demonstrate a mixture of singlet (63%) and triplet (37%) mixed STE emission, which contributes to a high photoluminescence quantum yield (60.5%). First-principles calculations suggest 48.34 meV energy per exciton stored by phonons in the distorted lattice of excited states, and 58 meV singlet-triplet splitting energy for the nanocrystals being consistent with the experimental measurements. The model clarifies long and controversial debates on ZnO emission in visible region, and the multiphoton excited singlet/triplet mixed STE emission is also observed.

By incorporating organic BHJ onto graphene, graphene/ZnO/PTB7-Th:IEICO-4F shows gate tunable photodetection/photostorage switching features for the implementation of both retinomorphic vision and memorial preprocessing functions.

In this article, we address the optomechanical effects in surface-enhanced resonant Raman scattering (SERRS) from a single molecule in a nano-particle on mirror (NPoM) nanocavity by developing a quantum master equation theory, which combines macroscopic quantum electrodynamics and electron-vibration interaction within the framework of open quantum system theory. We supplement the theory with electromagnetic simulations and time-dependent density functional theory calculations in order to study the SERRS of a methylene blue molecule in a realistic NPoM nanocavity. The simulations allow us not only to identify the conditions to achieve conventional optomechanical effects, such as vibrational pumping, non-linear scaling of Stokes and anti-Stokes scattering, but also to discovery distinct behaviors, such as the saturation of exciton population, the emergence of Mollow triplet side-bands, and higher-order Raman scattering. All in all, our study might guide further investigations of optomechanical effects in resonant Raman scattering., Comment: 15 pages; 9 figures

The quest for solar-blind photodetectors with outstanding optoelectronic properties and weak signals detection capability is essential for their applications in the field of imaging, communication, warning, etc. To date, Ga2O3 has demonstrated potential for high-performance solar-blind photodetectors. However, the performance usually decays superlinearly at low light intensities due to carrier-trapping effect, which limits the weak signal detection capability of Ga2O3 photodetectors. Herein, a Ga2O3 solar-blind photodetector with ultra-thin absorbing medium has been designed to restrain trapping of photo-generated carriers during the transporting process by shortening the carrier transport distance. Meanwhile, multiple-beam interference is employed to enhance the absorption efficiency of the Ga2O3 layer using an Al/Al2O3/Ga2O3 structure. Based on the ultra-thin absorbing medium with enhanced absorption efficiency, a 7 × 7 flexible photodetector array is developed, and the detectivity can reach 1.7 × 1015 Jones, which is among the best values ever reported for Ga2O3 photodetectors. Notably, the performance of the photodetector decays little as the illumination intensity is as weak as 5 nW/cm2, revealing the capacity to detect ultra-weak signals. In addition, the flexible photodetector array can execute the functions of imaging, spatial distribution of light source intensity, real-time light trajectory detection, etc. Our results may provide a route to high-performance solar-blind photodetectors for ultra-weak light detection.

Exploring materials with multiple properties who can endow a simple device with integrated functionalities has attracted enormous attention in the microelectronic field. One reason is the imperious demand for processors with continuously higher performance and totally new architecture. Combining ferroelectric with semiconducting properties is a promising solution. Here, we show that logic, in-memory computing, and optoelectrical logic and non-volatile computing functionalities can be integrated into a single transistor with ferroelectric semiconducting α-In2Se3 as the channel. Two-input AND, OR, and non-volatile NOR and NAND logic operations with current on/off ratios reaching up to five orders, good endurance (1000 operation cycles), and fast operating speed (10 μs) are realized. In addition, optoelectrical OR logic and non-volatile implication (IMP) operations, as well as ternary-input optoelectrical logic and in-memory computing functions are achieved by introducing light as an additional input signal. Our work highlights the potential of integrating complex logic functions and new-type computing into a simple device based on emerging ferroelectric semiconductors.

An unacceptable increase in antibacterial resistance has arisen due to the abuse of multiple classes of broad-spectrum antibiotics. Therefore, it is significant to develop new antibacterial agents, especially those that can accurately identify and kill specific bacteria. Herein, we demonstrate a kind of perilla-derived carbon nanodots (CNDs), integrating intrinsic advantages of luminescence and photodynamic, providing the opportunity to accurately identify and kill specific bacteria. The CNDs have an exotic-doped and π-conjugated core, vitalizing them near-infrared (NIR) absorption and emission properties with photoluminescence quantum yield of 21.1%; hydrophobic chains onto the surface of the CNDs make them to selectively stain Gram-positive bacteria by insertion into their membranes. Due to the strong absorption in NIR region, reactive oxygen species are in situ generated by the CNDs onto bacterial membranes under 660 nm irradiation, and 99.99% inactivation efficiency against Gram-positive bacteria within 5 min can be achieved. In vivo results demonstrate that the CNDs with photodynamic antibacterial property can eliminate the inflammation of the area affected by methicillin-resistant Staphylococcus aureus (MRSA), and enabling the wound to be cured quickly.

All-inorganic perovskite nanocrystals (NCs) are promising candidates for light-emitting diodes (LEDs) owing to their excellent optoelectronic properties. However, the pure-red perovskite LEDs (PeLEDs) available today made from mixed-halide CsPb(Br/I)

Piezochromic luminescent materials have shown great potential in advanced optoelectronic applications. However, most of luminescent materials usually undergo emission quenching under external stimuli. Herein, we demonstrate for the first time that the photoluminescence of carbon dots (CDs) confined within sodium hydroxide can be enhanced when high pressure is applied. They exhibit a 1.6-fold fluorescence enhancement compared with pristine CDs. Importantly, the enhanced fluorescence intensity can be retained after the release of pressure to ambient conditions. A combination of experimental analysis and theoretical simulations indicates that such an enhanced emission is mainly attributed to the strong confinement resulting from the sodium hydroxide matrix, which can separate the CDs spatially and restrict the nonradiative pathway. These results provide a rational strategy for manipulating the optical properties of CDs with enhanced and retainable photoluminescence (PL) performance, thus opening up a venue for designing luminescent CDs-based materials.

Intelligent systems have brought convenience to contemporary society. However, latency and poor-efficiency have been urgent problems for intelligence systems. Here, an infrared (IR) intelligent system fusing a non-contact IR thermopile sensor array fabricated by microelectromechanical system technology and an artificial neural network (ANN) algorithm is proposed, with the characteristics of high-efficiency and low-latency. The system is based on a designed near-sensor computing architecture, which can realize computing directly on edge devices without sending data to the cloud, resulting in reduced redundant data and decreased latency. The responsivity of the sensors affects the weight accuracy and computing speed of the ANN algorithm and further influences the accuracy and efficiency of the system. Transfer of graphene oxide (GO) material to the IR thermopile sensors with a proposed location transfer method is suggested to enhance the responsivity. The responsivity of the IR thermopiles with GO is up to 705.1 V/W, which is enhanced by 85.9% compared to that without GO. The system is applied to gesture recognition to study practicality. The recognition accuracy of the system with GO is 100%. This work provides an effective idea for studying a high-accuracy IR intelligent sensing system.

Two-dimensional (2D) infrared photodetectors always suffer from low quantum efficiency (QE) because of the limited atomically thin absorption. Here, we reported 2D black phosphorus (BP)/Bi 2 O 2 Se van der Waals (vdW) photodetectors with momentum-matching and band-alignment heterostructures to achieve high QE. The QE was largely improved by optimizing the generation, suppressing the recombination, and improving the collection of photocarriers. Note that momentum-matching BP/Bi 2 O 2 Se heterostructures in k -space lead to the highly efficient generation and transition of photocarriers. The recombination process can be largely suppressed by lattice mismatching–immune vdW interfaces. Furthermore, type II BP/Bi 2 O 2 Se vdW heterostructures could also assist fast transport and collection of photocarriers. By constructing momentum-matching and band-alignment heterostructures, a record-high QE of 84% at 1.3 micrometers and 76.5% at 2 micrometers have been achieved in BP/Bi 2 O 2 Se vdW photodetectors.

Room-temperature-operating highly sensitive mid-wavelength infrared (MWIR) photodetectors are utilized in a large number of important applications, including night vision, communications, and optical radar. Many previous studies have demonstrated uncooled MWIR photodetectors using 2D narrow-bandgap semiconductors. To date, most of these works have utilized atomically thin flakes, simple van der Waals (vdW) heterostructures, or atomically thin p-n junctions as absorbers, which have difficulty in meeting the requirements for state-of-the-art MWIR photodetectors with a blackbody response. Here, a fully depleted self-aligned MoS

Broadband photodetectors are of great importance for numerous optoelectronic applications. Two-dimensional (2D) tungsten disulfide (WS2), an important family member of transition-metal dichalcogenides (TMDs), has shown great potential for high-sensitivity photodetection due to its extraordinary properties. However, the inherent large bandgap of WS2 and the strong interface recombination impede the actualization of high-sensitivity broadband photodetectors. Here, we demonstrate the fabrication of an ultrabroadband WS2/Ge heterojunction photodetector through defect engineering and interface passivation. Thanks to the narrowed bandgap of WS2 induced by the vacancy defects, the effective surface modification with an ultrathin AlOx layer, and the well-designed vertical n-n heterojunction structure, the WS2/AlOx/Ge photodetector exhibits an excellent device performance in terms of a high responsivity of 634.5 mA/W, a large specific detectivity up to 4.3 × 1011 Jones, and an ultrafast response speed. Significantly, the device possesses an ultrawide spectral response spanning from deep ultraviolet (200 nm) to mid-wave infrared (MWIR) of 4.6 μm, along with a superior MWIR imaging capability at room temperature. The detection range has surpassed the WS2-based photodetectors in previous reports and is among the broadest for TMD-based photodetectors. Our work provides a strategy for the fabrication of high-performance ultrabroadband photodetectors based on 2D TMD materials.

Summary The extension of graphitic carbon nitride (g-CN) materials into optoelectronic applications beyond photocatalysis has long been anticipated due to their non-metallic composition, moderate electronic band gap, and excellent stability. However, large-scale synthesis of uniform two-dimensional (2D) g-CN films with high crystallinity and tunable thickness remains the bottleneck for their future applications in optoelectronic devices. Here, a vapor-phase transport-assisted condensation method has been developed for the wafer-scale synthesis of uniform 2D g-CN films with tunable thickness. First-principle calculations indicate the direct condensation from melem to heptazine-based carbon nitride enables the formation of high-quality g-CN films. A facile water-assisted transfer strategy is developed for subsequent fabrication on arbitrary substrate. A free-standing flexible photodetector array with strain-insensitive responsibility is demonstrated with the g-CN films as imaging pixels. This study provides a convenient route to wafer-scale growth of high-quality 2D g-CN films and paves the way to the g-CN-based electronic and optoelectronic devices.

Multi-photon-pumped lasing based on metal-halide perovskites is promising for nonlinear optics and practical frequency-upconversion devices in integrated photonic systems. However, at present almost all the multi-photon-pumped lasing emissions from perovskite microcavities were limited for two-photon excitation, and also suffered from a compromise in room temperature or low temperature operation conditions. In this study, based on the vapor-phase epitaxial CsPbBr3 microplatelets with high crystallinity, self-formed high-quality microcavities, and great thermal stability, low-threshold and high-quality factor whispering gallery mode lasing was realized under single-, two-, and three-photon excitation, and the lasing action is very stable under continuous pulsed laser irradiation (∼ 3.6 × 107 laser shots). More importantly, the three-photon-pumped lasing can be efficiently sustained at a high temperature of ∼ 400 K, and the characteristic temperature was determined to be as high as ∼ 152.6 K, indicating the highly temperature-insensitive gain threshold. Note that this is the first report on high-temperature three-photon-pumped lasing on perovskite microcavities. Moreover, an aggressive thermal cycling test (two cycles, 290-400-290 K) was further performed to indicate the stability and repeatability of the multi-photon-pumped lasing characteristics. It can be anticipated that the results obtained represent a significant step toward the temperature-insensitive frequency-upconversion lasing, inspiring the exploitation of advantageous perovskites for novel applications.

As one of the most important narrow bandgap ternary semiconductors, GaAs1−xSbx nanowires (NWs) have attracted extensive attention recently, due to the superior hole mobility and the tunable bandgap, which covers the whole near-infrared (NIR) region, for technological applications in next-generation high-performance electronics and NIR photodetection. However, it is still a challenge to the synthesis of high-quality GaAs1−xSbx NWs across the entire range of composition, resulting in the lack of correlation investigation among stoichiometry, microstructure, electronics, and NIR photodetection. Here, we demonstrate the success growth of high-quality GaAs1−xSbx NWs with full composition range by adopting a simple and low-cost surfactant-assisted solid source chemical vapor deposition method. All of the as-prepared NWs are uniform, smooth, and straight, without any phase segregation in all stoichiometric compositions. The lattice constants of each NW composition have been well correlated with the chemical stoichiometry and confirmed by high-resolution transmission electron microscopy, X-ray diffraction, and Raman spectrum. Moreover, with the increase of Sb concentration, the hole mobility of the as-fabricated field-effect-transistors and the responsivity and detectivity of the as-fabricated NIR photodetectors increase accordingly. All the results suggest a careful stoichiometric design is required for achieving optimal NW device performances.

Diamond is a promising ultrawide-bandgap semiconductor, which has drawn much attention in deep-ultraviolet optoelectronics and high-power electronics, due to its unique properties, including the highest thermal conductivity, strong radiation resistance, high breakdown electric field, chemical and thermal stability, and high carrier mobility. However, the optoelectronics applications have been restricted greatly by the small growth size of the single-crystal diamond. In this work, we demonstrate a solar-blind photodetector linear array based on high-quality 2-inch polycrystalline diamond, which has the advantage of large-area growth. The photodetector cells exhibit good uniformity, a responsivity of 45 mA/W at 228 nm with a cut-off wavelength of 240 nm, and a short response time of

A near-infrared (NIR) sub-ppm level photoacoustic sensor for hydrogen sulfide (H2S) using a differential Helmholtz resonator (DHR) as the photoacoustic cell (PAC) was presented. The core detection system was composed of a NIR diode laser with a center wavelength of 1578.13 nm, an Erbium-doped optical fiber amplifier (EDFA) with an output power of ∼120 mW, and a DHR. Finite element simulation software was used to analyze the influence of the DHR parameters on the resonant frequency and acoustic pressure distribution of the system. Through simulation and comparison, the volume of the DHR was 1/16 that of the conventional H-type PAC for a similar resonant frequency. The performance of the photoacoustic sensor was evaluated after optimizing the DHR structure and modulation frequency. The experimental results showed that the sensor had an excellent linear response to the gas concentration and the minimum detection limit (MDL) for H2S detection in differential mode can reach 460.8 ppb.

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.

Phosphorescent carbon nanodots (CNDs) have various attractive properties and potential applications, but it remains a formidable challenge to achieve large-scale phosphorescent CNDs limited by current methods. Herein, a large-scale synthesis method for phosphorescent CNDs has been demonstrated via precursors’ self-exothermic reaction at room temperature. The as-prepared CNDs show fluorescence and phosphorescence property, which are comparable with that synthesized by solvothermal and microwave method. Experimental and computational studies indicate that exotic atom doped sp2 hybridized carbon core works as an emissive center, which facilities the intersystem crossing from singlet state to triplet state. The CNDs show phosphorescence with tunable lifetimes from 193 ms to 1.13 s at different temperatures. The demonstration of large-scale synthesis of phosphorescent CNDs at room temperature opens up a new window for room temperature fabrication phosphorescent CNDs.

Although vanadium (V)-based sulfides have been investigated as cathodes for aqueous zinc-ion batteries (ZIBs), the performance improvement and the intrinsic zinc-ion (Zn2+) storage mechanism revelation is still challenging. Here, VS4@rGO composite with optimized morphology is designed and exhibits ultrahigh specific capacity (450 mA h g−1 at 0.5 A g−1) and high-rate capability (313.8 mA h g−1 at 10 A g−1) when applied as cathode material for aqueous ZIBs. Furthermore, the VS4@rGO cathode presents long-life cycling stability with capacity retention of ∼82% after 3500 cycles at 10 A g−1. The structural evolution, redox, and degradation mechanisms of VS4 during (dis)charge processes are further probed by in situ XRD/Raman techniques and TEM analysis. Our results indicate that the main energy storage mechanism is derived from the intercalation/deintercalation reactions in the open channels of VS4. Notably, an irreversible phase transition of VS4 into Zn3(OH)2V2O7·2H2O (ZVO) during the charging process and the further transition from ZVO to ZnV3O8 during long-term cycles are also observed, which might be the main reason leading to the capacity degradation of VS4@rGO. Our study further improves the electrochemical performance of VS4 in aqueous ZIBs through morphology design and provides new insights into the energy storage and performance degradation mechanisms of Zn2+ storage in VS4, and thus may endow the large-scale application of V-based sulfides for energy storage systems.

Photomemories offer great opportunities for multifunctional integration of optical sensing, data storage, and processing into one single device. However, little attention has been paid to photomemories working in the solar-blind region so far, which may have unique advantages of insusceptibility to ambient light and higher capacity. Herein, we propose and demonstrate a Ga2O3 based solar-blind photomemory array with logic, arithmetic, and optoelectronic memory functions. The device shows n-type field effect-transistor performance with an on/off ratio as high as 106, a responsivity of 8 × 103 A W−1, and a detectivity of 1.42 × 1014 Jones, all of which are amongst the best values ever reported for Ga2O3 based photodetectors. Based on the trapping and de-trapping process of holes in Ga2O3, multilevel data storage can be realized from the device. Simultaneously, the optical and electrical mixed basic logic of reconfigurable “AND” and “OR” operations have been realized in a single cell through the co-regulation of solar-blind light and the grid voltage. In addition, the photomemory can perform counting and addition operations, and the photomemory array can be utilized to realize solar-blind image storage. The results suggest that Ga2O3 may have potential applications in high-performance information storage, computing, and communications.

Light polarization could provide critical visual information (e.g., surface roughness, geometry, or orientation) of the imaged objects beyond prevailing signals of intensity and wavelength. The polarization imaging technology thus has a large potential in broad fields such as object detection. However, intricate polarization coding is often required in these fields, and the existing complicated lensed system and polarizers have limited the miniaturization capabilities of the integrated imaging sensor. In this study, we demonstrate the utilization of two-dimensional (2D) in-plane anisotropic α-GeSe semiconductor to realize the polarizer-free polarization-sensitive visible/near-infrared (VIS-NIR) photodetector/imager. As the key part of the sensor system, this prototype Au/GeSe/Au photodetector exhibits impressive performances in terms of high sensitivity, broad spectral response, and fast-speed operation (∼103 AW−1 400–1050 nm, and 22.7/49.5 µs). Further, this device demonstrates unique polarization sensitivity in the spectral range of 690–1050 nm and broadband absorption of light polarized preferentially in the γ-direction, as predicted by the analysis of optical transition behavior in α-GeSe. Then we have successfully incorporated the 2D GeSe device into an imaging system for the polarization imaging and captured the polarization information of the radiant target with a high contrast ratio of 3.45 at 808 nm (NIR band). This proposed imager reveals the ability to sense dual-band polarization signals in the scene without polarizers and paves the way for polarimetric imaging sensor arrays for advanced applications.

Perovskite light-emitting diodes (LEDs) are emerging light sources for next-generation lighting and display technologies; however, their development is greatly plagued by difficulty in achieving yellow electroluminescence, environmental instability, and lead toxicity. Copper halide CsCu

Inspired by the great success of ultrathin two-dimensional (2D) layered crystals, more and more attention is being paid to preparing 2D nanostructures from non-layered materials. They can significantly enrich the 2D materials and 2D heterostructures family, extend their application prospects, and bring us distinct properties from their bulk counterparts due to the strong 2D confinement effect. However, the realization of 2D non-layered semiconductors with strong light-harvesting capability and the ability to construct high-performance 2D heterostructures is still a critical challenge. Herein, we successfully synthesized 2D PbSe semiconductors with a large lateral dimension and ultrathin thickness via van der Waals epitaxy. The fabricated 2D PbSe device exhibits good electrical conductivity and superior multi-wavelength photoresponse performance with high responsivity (∼10

Overcoming the sub-5 nm gate length limit and decreasing the power dissipation are two main objects in the electronics research field. Besides advanced engineering techniques, considering new material systems may be helpful. Here, we demonstrate two-dimensional (2D) subthermionic field-effect transistors (FETs) with sub-5 nm gate lengths based on ferroelectric (FE) van der Waals heterostructures (vdWHs). The FE vdWHs are composed of graphene, MoS2, and CuInP2S6 acting as 2D contacts, channels, and ferroelectric dielectric layers, respectively. We first show that the as-fabricated long-channel device exhibits nearly hysteresis-free subthermionic switching over three orders of magnitude of drain current at room temperature. Further, we fabricate short-channel subthermionic FETs using metallic carbon nanotubes as effective gate terminals. A typical device shows subthermionic switching over five-to-six orders of magnitude of drain current with a minimum subthreshold swing of 6.1 mV/dec at room temperature. Our results indicate that 2D materials system is promising for advanced highly-integrated energy-efficient electronic devices.

In this study, for the first time, the integration of nontoxic ternary copper halide Cs3Cu2I5 with one-dimensional Si nanowires (NWs) was reported to achieve an ultraviolet (UV)-enhanced Si NW broa...

Hydrogen peroxide (H2O2) is an important product generated in the body and related to many pathophysiological processes and glucose metabolism disorder can cause many fatal diseases in living bodies. Therefore, the sensing of H2O2 and glucose is of great significance in disease diagnostics and treatment. Fluorescent carbon dots (CDs) are one new class of nanoprobes for H2O2 and glucose. Nevertheless, the CD-based sensor is always based on its fluorescence response, which is influenced by the auto-fluorescent interference. Herein, efficient fluorescent CDs were synthesized by one-pot solvothermal method, and the CDs exhibit bright and persistent deep-red (DR) chemiluminescence (CL) in bis(2,4,6-trichlorophenyl) oxalate and H2O2 solution with a CL quantum yield of (8.22 ± 0.30) × 10−3, which is amongst the highest values in ever reported nanomaterials for chemical analysis. Employing the CDs as CL nanoprobes, sensitive sensing for H2O2 has been achieved with a detection limit of 11.7 μM, and further for glucose detection with a detection limit of 12.6 μM. The DR CL CDs is promising to be applied in blood glucose analysis or in vivo biosensor.

The manipulation of magnetism provides a unique opportunity for the development of data storage and spintronic applications. Until now, electrical control, pressure tuning, stacking structure dependence, and nanoscale engineering have been realized. However, as the dimensions are decreased, the decrease of the ferromagnetism phase transition temperature (Tc) is a universal trend in ferromagnets. Here, we make a breakthrough to realize the synthesis of 1 and 2 unit cell (UC) Cr2Te3 and discover a room-temperature ferromagnetism in two-dimensional Cr2Te3. The newly observed Tc increases strongly from 160 K in the thick flake (40.3 nm) to 280 K in 6 UC Cr2Te3 (7.1 nm). The magnetization and anomalous Hall effect measurements provided unambiguous evidence for the existence of spontaneous magnetization at room temperature. The theoretical model revealed that the reconstruction of Cr2Te3 could result in anomalous thickness-dependent Tc. This dimension tuning method opens up a new avenue for manipulation of ferromagnetism.