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An unstable solid electrolyte interphase (SEI) and chaotic lithium ion flux are key impediments to commercial high-energy-density lithium batteries because of the uncontrolled growth of rigid lithium dendrites, which would pierce through the conventional polypropylene (PP) separator, causing short circuit and safety issues. Herein, the homogenization of lithium ion flux and the generation of stable SEI layers on lithium anodes were achieved via coating a fluorine-functionalized Ti3C2 (F-Ti3C2) nanosheets on PP separator (F-Ti3C2@PP). F-Ti3C2 nanosheets provide abundant ions pathways to homogeneously manipulate lithium ion flux and increase the Young’s modulus and electrolyte wettability of the separators. In addition, F species derived from the F-Ti3C2 nanosheets would promote the formation of LiF-rich SEI film. The synergistic effect contribute to the uniform lithium deposition. Symmetric Li|Li, asymmetric Li|Cu and full Li|LiFePO4 cells incorporated with the modified separators exhibit improved electrochemical performance even under lean electrolyte conditions. This work provides a feasible strategy to improve the performance of lithium batteries through both fluoridized SEI formation and lithium ion flux manipulation.

In this study, a Ni-based sludge coke catalyst was prepared by mechanical ball-milling and mild injection to produce high-quality hydrogen-rich gas through the gasification of sludge. The effects of different factors, such as ball milling time, gasification temperature, NiO loading rate and steam flow rate on the gasification characteristics of the Ni-based sludge coke were investigated. The results showed that the optimum process conditions were the ball-milling time of 10 min, gasification temperature of 900 °C, NiO loading rate of 20% and steam flow rate of 1 g min−1. Under these conditions, the gas production efficiency was improved, with gas and H2 production rates of 0.76 m3 kg−1 and 0.34 m3 kg−1, respectively. Temperature is a key factor of gasification. The gas yield and H2 yield at 900 °C were 38 times and 85 times higher than those at 500 °C, respectively. The FTIR and XRD analysis further revealed that the selection of an appropriate ball-milling time caused the NiO to be evenly distributed on the biochar, thereby improving its catalytic performance. While, increasing the temperature promoted the full pyrolysis of organic matter and the secondary decomposition of tar, which improved the gasification efficiency. The results obtained here allow optimization of the technical parameters for the generation of hydrogen-rich gas by sludge gasification, thereby providing a theoretical basis for the production of high-quality gas through the catalytic gasification of Ni-based biochar.

A thermal protection material (TPM) was prepared using Al2O3-phosphate, expanded aluminosilicate, and phenolics through compression molding and the gradient heating reaction technique, and the effect of the high-temperature treatment on the properties of the composites were investigated. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used to analyze the structures and compositions of the composites. After the high-temperature treatment, the composites exhibited increased porosity, decreased density, and generated SiC particles with high strength and temperature resistance. The prepared composites have high compressive strength and compression deformation ability of the bending point. Thermogravimetric analysis, coefficient of thermal conductivity measurements, and expansion analysis were carried out to evaluate the thermal properties of the composites, and the effects of the preparation conditions on the thermal properties of the composites were investigated. The results showed that the prepared composites exhibited complete morphology, excellent high-temperature resistance, high compressive strength and toughness, and low thermal conductivity before and after the high-temperature treatment at 1000 °C, and hence showed great potential for future thermal protection applications.

High-volume fly ash (FA) cement presented a slow setting and lower early compressive strength, restricting the utilization in cemented paste backfill (CPB). The present work investigated the feasibility of using metakaolin with various particle sizes and content to modify the properties of FA cement. Reaction kinetics, rheological properties, setting time, compressive strength, hydration products, and the CPB samples' microstructure were thoroughly studied. The results showed that 5 wt% of super-fine metakaolin (SMK) could strongly promote the binder hydration, leading to the formation of a more compact matrix with higher early compressive strength. The 3 d-compressive strength of the CPB samples was increased by around 216% after replaced by 5 wt% of SMK. Besides, the binder doped with 5 wt% SMK showed better environmental and cost performance.

Dual-color emission in a single perovskite layer would make perovskite light-emitting devices (PLEDs) more competitive compared with other display technologies. However, due to the carrier dynamics in a blended perovskite film and the low reaction activation energy of the halide exchange reaction, it is very difficult to achieve the dual-color emission in a perovskite layer. Here, dual-color electroluminescence (EL) emission in a single perovskite layer has been realized by slowing the energy transfer from wide-bandgap energy levels to narrow-bandgap energy levels. Moreover, the EL spectra can be controlled by modulating the composition of the perovskite layer. When the amount of CH3NH3I(MAI) in the precursor was varied, white emission with CIE coordinates of (0.33, 0.34) could be achieved. Our work proposes a new strategy for white emission from PLEDs. Also, the analysis and discussion of carrier dynamics in this work may help to enhance our understanding of the working mechanism of PLEDs.

Strain engineering can effectively improve the energy band degeneracy of two-dimensional transition metal dichalcogenides so that they exhibit good thermoelectric properties under strain. In this work, we have studied the phonon, electronic, thermal, and thermoelectric properties of 1T-phase monolayer HfS2 with biaxial strain based on first-principles calculations combined with Boltzmann equations. At 0% strain, the results show that the lattice thermal conductivity of monolayer HfS2 is 5.01 W m-1 K-1 and the electronic thermal conductivities of n-type and p-type doped monolayer HfS2 are 2.94 and 0.39 W m-1 K-1, respectively, when the doping concentration is around 5 × 1012 cm-2. The power factors of the n-type and p-type doped monolayer HfS2 are different, 29.4 and 1.6 mW mK-2, respectively. Finally, the maximum ZT value of the n-type monolayer HfS2 is 1.09, which is higher than 0.09 of the p-type monolayer HfS2. Under biaxial strain, for n-type HfS2, the lattice thermal conductivity, the electronic thermal conductivity, and the power factor are 1.55 W m-1 K-1, 1.44 W m-1 K-1, and 22.9 mW mK-2 at 6% strain, respectively. Based on the above factor, the ZT value reaches its maximum of 2.29 at 6% strain. For p-type HfS2, the lattice thermal conductivity and the electronic thermal conductivity are 1.12 and 1.53 W m-1 K-1 at 7% strain, respectively. Moreover, the power factor is greatly improved to 29.5 mW mK-2. Finally, the maximum ZT value of the p-type monolayer HfS2 is 3.35 at 7% strain. It is obvious that strain can greatly improve the thermoelectric performance of monolayer HfS2, especially for p-type HfS2. We hope that the research results can provide data references for future experimental exploration.

This study presents a switchable Doherty power amplifier (S‐DPA) based on dual compensating reactance and adjusted drain voltage with 124% fractional bandwidth (FBW) using single‐input architecture. The proposed S‐DPA can be operated in wideband mode (WB‐MOD) and dual‐band mode (DB‐MOD) with a larger power back‐off region through one‐click switching directly. The needed back‐off impedance in both operation modes is achieved by using the dual compensating reactance for bandwidth extension. Meanwhile, a load modulation enhancement technique through adjusting the drain voltage of both the carrier and peaking amplifiers is proposed for proper load modulation in DB‐MOD. To verify the proposed techniques, an S‐DPA was designed and fabricated. Measurement results show that the proposed S‐DPA has an efficiency of 51.3%–70.3% at saturated power of higher than 43.4 dBm over the frequency band of 0.8–3.4 GHz with 124% FBW. The 6‐dB back‐off efficiency in WB‐MOD (1.3–2.9 GHz) is 45.3%–56.1% and the 8‐dB back‐off efficiency in DB‐MOD (0.8–1.3 GHz & 2.9–3.4 GHz) is 41.6%–57.9%. 80‐MHz modulated signals with 6.2‐dB and 8.2‐dB peak to average power ratios are used to evaluate the modulated signal performance in two modes. The DPA can achieve an average efficiency of up to 56% with high linearity after digital pre‐distortion linearisation.

Objective. To optimize the preparation formula and technology of Chuilian Jianpi granules. Methods. The formulation and preparation process were optimized by single factor experiment and response surface analysis, with the molding rate, hygroscopicity, and fluidity of particles as the comprehensive evaluation indexes, and the comprehensive score as the response value according to different weights. To further evaluate the stability and feasibility of the preparation formulation and technology, the physical fingerprint of the granules was constructed by seven indicators including particle tap density, bulk density, hygroscopicity, water content, angle of repose, Hausner ratio, and relative homogeneity index. Results. The optimum formula conditions of Chuilian Jianpi granules were as follows: the dosage ratio of drug to adjuvant was 1 : 0.8, lactose:mannitol = 1.5 : 1, and the amount of wetting agent (90% ethanol) was 25% of the granules, with high-speed stirring granulation. The similarity of the physical fingerprints of the 10 batches of Chuilian Jianpi granules was high, which is above 98.5%. Conclusion. The optimized preparation technology was stable and feasible, which can provide reference for the development of Chuilian Jianpi granules and other Chinese medicine granules.

Annealing has been widely recognized as a crucial approach to modify the microstructure and enhance the coercivity of Nd–Fe–B magnets. However, in the context of Nd–Y–Ce–Fe–B magnets with multiple rare earths (REs) exhibiting different diffusion behaviors, annealing effects on the magnetic properties become more complicated and remain unknown. In present work, through a comparative study between as-sintered and annealed Nd–Y–Ce–Fe–B magnet upon 50 wt% Y–Ce co-substitution of total REs, we found that annealing process surprisingly enhances the remanence from 1.17 to 1.20 T, with simultaneous coercivity increment from 612.9 to 660.7 kA·m−1, resulting in drastically improved maximum energy product from 242.0 to 263.5 kJ·m−3. Such a peculiar remanence enhancement is closely correlated to the preferential Y/Nd infiltration into RE2Fe14B main phase and Ce segregation into REFe2 intergranular phase, which consequently improve the intrinsic magnetism, as evaluated by Curie temperature (TC), saturation magnetic polarization (JS) and magnetocrystalline anisotropy field (HA). Present work delights that different metallurgical behaviors of Nd/Y/Ce exert influential effects on the intrinsic and extrinsic magnetic properties and provide a novel approach toward high-performance 2:14:1-type permanent magnets based on abundant RE mixtures.

Multi-pass friction stir processing (M-FSP) was performed to repair the interface defects of AA5083/T2 copper explosive composite plates. The interface morphology and its bonding mechanism were explored. The results show that higher rotation speed and lower transverse speed produce more heat generated during FSP. The defect-free and good mechanical properties of the AA5083/T2 copper composite plate can be obtained under the condition of the rotation speed of 1200 r/min, the transverse speed of 30 mm/min and the overlap of 2/24. Moreover, M-FSP changes the interface bonding mechanism from metallurgical bonding to vortex connection, improving the bonding strength of composite plate, which can guarantee the repairing quality of composite plates.

In this paper, a development of low cost, miniature, highly integration broadband RF transceiver front-end using the high selectivity hybrid resonator RF bandpass filters, and diplexer integrated w...

In this study, we present a wavelength sensor that is capable of distinguishing the spectrum in the range from ultraviolet (UV) to near-infrared (NIR) light. The filterless device is composed of two horizontally stacking PdSe2/20 μm Si/PdSe2 heterojunction photodetectors with a photovoltaic (PV) behavior, which makes it possible for the device to work at 0 bias voltage. Due to the relatively small thickness of Si and the wavelength-dependent absorption coefficient, the two PdSe2/20 μm Si/PdSe2 photodetectors according to theoretical simulation display a sharp contrast in distribution of the photoabsorption rate. As a result, the photocurrents of both photodetectors evolve in completely different ways with increasing wavelengths, leading to a monotonic decrease in the photocurrent ratio from 6800 to 22 when the wavelength gradually increases from 265 to 1050 nm. The corresponding relationship between both the photocurrent ratio and wavelength can be easily described by the monotonic function, which can help to precisely determine the wavelength in the range from 265 to 1050 nm, with an average relative error less than ±1.6%. It is also revealed that by slightly revising the monotonic function, the wavelength in other different temperatures can also be estimated.

In order to investigate the interactions between laser and powder particles in directional energy deposition (DED) additive manufacturing (AM), a coupled electromagnetic wave heating (EWH) model is...

Deep-ultraviolet (DUV) photodetection has garnered extensive research interest for its vital applications in many military and civil fields. In this work, we present the synthesis of a large-area two-dimensional (2D) PdTe2 multilayer, which can be directly transferred onto a GaN substrate to construct a vertical heterostructure for visible-blind DUV photodetection. Upon 265 nm light irradiation, the heterostructure displays a distinct photovoltaic behavior, enabling it to serve as a self-driven photodetector. The important photoresponse parameters, such as ${I}_{light}/{I}_{dark}$ ratio, responsivity, specific detectivity and DUV/visible (265 nm/450 nm) rejection ratio reach as high as 106, 168.5 mA/W, $5.3 \times 10^{12}$ Jones, and 104, respectively, at zero bias. The responsivity can be further enhanced to 254.6 mA/W by applying a small reverse bias of −1.0 V. In addition, the photodetector can function as a DUV light image sensor to reliably record an “H” pattern with a decent resolution. The present study paves a way for designing high-performance cost-effective DUV photodetectors towards practical optoelectronic applications.

For investigating the regulatory effects of the 1,3,5-trithiane (3S) in the formation of silver-alkynyl clusters, two new tetra-nucleus silver-alkynyl clusters, namely, [(3S)4Ag4(PhC≡C)(OTf)2]·OTf·CH3OH (1, OTf = CF3SO3−), and [(3S)2Ag4(tBuC≡C)(tfa)3]n (2, tfa = CF3CO2−), were synthesized and their unique structures were investigated by single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy, and powder X-ray diffraction analysis. Cluster 1 was a discrete cationic tetra-nucleus cluster co-ligated by 3S and phenylacetylene. Cluster 2 was a 2D coordination polymer based on a structurally similar tetra-nucleus cluster linking by 3S. Both clusters show excellent thermal stability and bright solid-state photoluminescence properties at room temperature. This work opens the door to using the supramolecular ligand-thiocrown ether to synthesize Ag clusters of attractive properties.

Post-heat treatment takes a key role for the enhancement of mechanical properties in selective laser melting (SLM) additive manufacturing (AM) of 6xxx series aluminum alloy. To understand the basic mechanism for changes of mechanical properties in the SLM process and the following post-heat treatment, the finite element model and the precipitate evolution (PE) model of SLM AM were established and combined. Results show that the hardness of the fabricated AM component can reach 91.47 HV at 170 °C for 18.8 h, which is 63.1% higher than the as-fabricated state. The comparison of hardness in as-fabricated AM component with experiments shows the validity of the proposed models. Further work on chemical composition shows that the selection of powder particle can greatly affect the hardness of the fabricated AM component. In the selection of 6xxx series aluminum alloy powder, higher Mg and Si contents in their solubility domains lead to higher generation of Mg2Si nano-size precipitates and then cause higher hardness of AM specimen. After the optimal post-heat treatment, the maximum hardness can exceed 100 HV.

Although intermolecular aggregation-induced emission (AIE) has been extensively studied in nanocluster science, it remains challenging to activate AIE via intracluster aggregation (i.e., the aggreg...

The polarization effect has been a powerful tool in controlling the morphology of metal nanoparticles. However, a precise investigation of the polarization effect has been a challenging pursuit for a long time, and little has been achieved for analysis at the atomic level. Here the atomic-level analysis of the polarization effect in controlling the morphologies of metal nanoclusters is reported. By simply regulating the counterions, the controllable transformation from Pt1Ag28(S-PhMe2)x(S-Adm)18−x(PPh3)4 (x = 0–6, Pt1Ag28-2) to Pt1Ag24(S-PhMe2)18 (Pt1Ag24) with a spherical configuration or to Pt1Ag28(S-Adm)18(PPh3)4 (Pt1Ag28-1) with a tetrahedral configuration has been accomplished. In addition, the spherical or tetrahedral configuration of the clusters could be reversibly transformed by re-regulating the proportion of counterions with opposite charges. More significantly, the configuration transformation rate has been meticulously manipulated by regulating the polarization effect of the ions on the parent nanoclusters. The observations in this paper provide an intriguing nanomodel that enables the polarization effect to be understood at the atomic level., Based on the inter-conversion between Pt1Ag24(SR)18 and Pt1Ag28(SR)18(PPh3)4, an insight into the polarization effect in controlling the morphology of metal nanoparticles is presented.

Alloyed green-emitting CdZnSeS/ZnS quantum dots (QDs) demonstrate potential applications in solid-state lighting and displays owing to their various advantages, such as high color purity, light conversion efficiency, and color rendering index. However, their applications in white light-emitting diodes (WLEDs) are limited by their poor photostabilities on blue-emitting gallium nitride (GaN) LED chips. In this study, the effect of the specific surface area (SSA) in the coating layers on the photostabilities of QDs was investigated. SSA was adjusted by controlling the proportions of dense aluminum oxide (AlOX) layers and porous silica dioxide (SiO2) layers to fabricate QD protective layers via a catalyst-free sol-gel method. The results showed that the synthesized AlOX possessing the lowest SSA among the synthesis protective layers presented the best QD photostabilities on the LED chips. Moreover, they exhibited a 9.9-fold increase in the operational lifetime (T80) compared to that of pristine QDs. In addition, the QD-based WLED achieved an excellent display performance with a wide color gamut (115%) of the National Television System Committee (NTSC) color gamut standard. This approach offers a promising strategy for enhancing the QD photostabilities for applications in solid-state lighting and displays by coating the protective layers on the QD surface.

Tibetan butter (TB), generally called butter, is a solid oil product extracted from yak milk in the Qinghai-Tibet plateau area. However, due to the limitations of raw material sources and production technology, there is a shortage of TB, so it is important to find substitutes of TB. This paper studied the crystallization behavior of six kinds of commercial TB products in Tibet to provide the theoretical basis for the development of TB substitutes for the production of TB lamps and flowers. This study assessed the crystallization behaviors of the TB samples, including isothermal crystallization process and non-isothermal crystallization process. The microstructure, isothermal crystallization of TB were evaluated by polarized light microscopy and low-pulse NMR spectrometry, respectively. The non-isothermal crystallization process of TB under temperature scanning were investigated using Rheometer, and the crystallization behavior under different cooling rates were determined by differential scanning calorimetry (DSC) procedures. The results showed that the TB was crystallized at a higher supercooling (−10, 0 and 10 °C). Dimensional growth is dominant; at 20 °C, spiral growth dominates. The TB has complex crystallization nucleation behavior. The crystal types of TB are mainly β'-crystal form and β'-like crystal form. The lower the cooling rate, the shorter the crystallization induction time, and the more the number of crystal nuclei. Therefore, during producing TB substitutes in the factory, the cooling rate can be controlled at 10 °C/min to reduce energy consumption and production costs.

In the shatter regime of a Whipple shield, a large central fragment makes a significant contribution to the damage-causing capacity of the debris cloud. Herein we present a feasible scheme for the identification and measurement of this large central fragment and propose an alternative approach to the ballistic limit equation (BLE) for the Whipple shield, deducing an alternative ballistic limit in the shatter regime based on the large central fragment’s characteristics. This alternative BLE is compared with the phenomenological Whipple BLE, the JSC Whipple BLE and the Ryan curve. Our alternative BLE, modified at the incipient fragmentation and completed fragmentation point, is shown to agree well with experimental results.

Al–TiO2–C–La2O3 refiners were synthesized by the in-situ exothermic dispersion method using TiO2, C, Al and La2O3 powders as raw materials. Scanning electron microscopy equipped with energy dispersive X-ray spectrometry and X-ray diffraction were used to investigate the microstructures of the Al–TiO2–C–La2O3 refiners. Commercial pure aluminum was refined by the Al–TiO2–C–La2O3 refiners, aimed at investigating refining performance and the resistance to recession. The results show that the Al–TiO2– C–La2O3 refiner with 0.2% La2O3 is composed of α-Al, blocky Al3Ti, dispersive Al2O3 and TiC, which has a better refining effect on commercial pure aluminum than the Al– TiO2–C refiner. The average grain size refined by the above refiner is about 80 μm and it performs better and has a longer refining effect. The grain structure refined by Al–TiO2– C–La2O3 becomes finer within 5 min and remains the same after 120 min, while refined by the Al–TiO2–C refiner the equivalent times are 10 min and 30 min respectively.

Traditional methods of preparing regular-shaped silver chloride nanoparticles for antiseptic use are complex. Squarelike AgCl nanoparticles with an average size of about 400 nm were prepared using ...

For the control of low-frequency noise in complex external-pressure environment, a new two-dimensional phononic crystal plate which is made of the lead stub with rubber coatings connected by narrow...

This letter presents a novel harmonic impedance matching technique by using a parallel LC resonate block after the combining point to design a fully integrated high-efficiency Doherty power amplifier (DPA). The second harmonic impedances of both carrier and peaking amplifiers can be matched to the optimal area with only one harmonic tuner easily. The insertion loss and size of the output matching network (OMN) can be reduced. For verification, a 4.6–5.2-GHz monolithic microwave integrated circuit DPA was designed and fabricated using a 0.25- $\mu \text{m}$ gallium nitride (GaN)-HEMT process. Experimental results show that a saturated power of 41.8–42.1 dBm, a saturated drain efficiency (DE) of 63.8%–68.4%, and a 6-dB back-off DE of 53.3%–57.4% are achieved from 4.6 to 5.2 GHz. For a 160-MHz modulated signal, a high DE of 54% with good linearity after linearization is obtained at an average output power of 35.6 dBm.

The emergence of optical Internet of Things (optical-IoT) for sixth-generation (6G) networks has been envisaged to relieve the bandwidth congestion in the conventional radio frequency (RF) channel, and to support the ever-increasing number of smart devices. Among the plethora of device innovations deemed essential for fortifying the development, herein we report on the visible-to-near-infrared color-conversion luminescent-dyes based on lead sulphide quantum dots (PbS QDs), so as to achieve an eye-safe high-speed optical link. The solution-processed PbS QDs exhibited strong absorption in the visible range, radiative recombination lifetime of 6.4 $\mu$s, as well as high photoluminescence quantum yield of up to 88%. Our proof-of-principle demonstration based on an orthogonal frequency-division multiplexing (OFDM) modulation scheme established an infrared data transmission of 0.27 Mbit/s, readily supporting an indoor optical-IoT system, and shed light on the possibility for PbS-integrated transceivers in supporting remote access control of multiple nodes. We further envisaged that our investigations could find applications in future development of solution-processable PbS-integrated luminescent fibers, concentrators, and waveguides for high-speed optical receivers.

One recent development to improve optoelectronic properties of perovskites is to use a larger cation for multication engineering. The chain-like ethylammonium (EA) [(C2H5)NH3]+ cation is more likely to form a one-dimensional perovskite structure; however, there is no remarkable evidence in this connection. Therefore, in this work, for the first time, the EA cation as an alternative cation was introduced into FAPbBr3 cubic crystals to explore the stabilities and optoelectronic properties of mixed FA x EA(1-x)PbBr3 perovskites. The results indicate that replacing FA with EA is a more effective way to realize band gap tuning and morphology transformation between the cubic shape and microwires. The tuned band gap of perovskite is due to the variation of Pb-Br-Pb angles induced by the insertion of the larger EA cation. We highlight that this work provides new physical insights into the correlation between the engineering of organic cations and the formation of perovskite microwires and the tunable band gap. This observation will help us to find new ways to grow perovskite microwires and subsequently study the optoelectronic performance of low-dimensional perovskites devices.

揭示水盐效应对膨润土混合土的渗透系数和不排水剪切强度的影响。 1. 通过核磁及扫描电镜等手段从微观角度解释混合土力学指标的变化规律;2. 建立水盐效应下评估混合土的渗透系数和不排水剪切强度的经验关系式。 1. 通过开展常规渗透试验和十字板剪切试验,揭示混合土力学指标的变化规律;2. 通过微观试验,分析影响力学指标的主要控制因素;3. 通过收集文献数据,验证经验关系式的可行性和有效性。 1. 混合土的渗透系数随着膨润土含量的升高而降低;用盐水饱和的试样,其渗透系数偏大,而不排水剪切强度呈相反的趋势。2. 由核磁试验获得的试样孔隙分布可用来解释其渗透系数的变化规律。3. 文中提出的经验关系式能够较好地预测混合土的力学特性,包括渗透系数和不排水剪切强度。

The frequent occurrence of coal spontaneous combustion (CSC) poses a serious threat to coal mine production safety. Inhibitor fire extinguishing technology has therefore played an important role in reducing CSC in recent years. Microcapsule material is a combined fire extinguishing material that has shown a good effect in preventing CSC. In this study, microcapsule materials were fabricated with short-chain ammonium polyphosphate as the core material and melamine–formaldehyde resin as the capsule material. The microcapsule materials were uniformly mixed with coal samples according to mass ratios of 1:4, 1:5, and 1:6. The quality change of the microcapsule material during heating was detected from thermogravimetric experiments. The results show that microcapsule material decomposition can be divided into five stages. The ammonium polyphosphate begins to decompose at 151.1 °C and the decomposition rate of the microcapsule material reaches a maximum at 200 °C Fourier transform infrared spectroscopy was used to detect the distribution of functional groups during coal oxidation before and after the addition of different microcapsule ratios. The results show that microcapsule materials can reduce the number of hydroxyl and aliphatic hydrocarbons in coal and enhance the stability of aromatic hydrocarbons and oxygenic functional groups. We also performed synchronous thermal analyzer experiments to monitor the temperatures of each characteristic point in the coal oxidation and heating process. The results show that the microcapsule material can reduce the coal mass loss rate, delay the temperature of heat equilibrium by around 100 °C reduce the heat release by more than 4560 J g–1, and increase the maximum temperature of the heat release rate by at least 14 °C. These materials therefore effectively reduce the coal-oxygen composite reaction rate and delay the CSC process.

Hierarchical 3D nanolayered Zr-2.5Nb has high strength, strain hardening and ductility because of the 3D α/β-Zr networks, which is a promising structural material for nuclear reactor. However, excellent thermal stability is of great importance for materials service in nuclear reactor. Here, we study thermal stability of the hierarchical 3D nanolayered Zr-2.5Nb. After 1 h annealing at various temperatures below 700 °C, α-Zr layer thickness only has a slightly increase. The hardness, yield strength and uniform elongation of the sample remain unchanged. Interface orientation relationship and layer morphology keep stable after annealing, indicating high thermal stability. The duplex phase structures coarsen quickly after annealing at 1000 °C. An obvious increase in hardness and yield strength was observed when sample annealed at 300 °C, which relates to the precipitation of ωiso phase in β-Zr. Controlling the number of ωiso phase is likely a strategy to further enhance the strength and ductility of the alloy.

A wavelength sensor as a representative optoelectronic device plays an important role in many fields including visible light communication, medical diagnosis, and image recognition. In this study, a wavelength-sensitive detector with a new operation mechanism was reported. The as-proposed wavelength sensor which is composed of two parallel PtSe2/thin Si Schottky junction photodetectors is capable of distinguishing wavelength in the range from ultraviolet to near infrared (UV-NIR) light (265 to 1050 nm), in that the relationship between the photocurrent ratio of both photodetectors and incident wavelength can be numerically described by a monotonic function. The unique operation mechanism of the thin Si based wavelength sensor was unveiled by theoretical simulation based on Synopsys Sentaurus Technology Computer Aided Design (TCAD). Remarkably, the wavelength sensor has an average absolute error of ±4.05 nm and an average relative error less than ±0.56%, which are much better than previously reported devices. What is more, extensive analysis was performed to reveal how and to what extent the working temperature and incident light intensity, and the thickness of the PtSe2 layer will influence the performance of the wavelength sensor.

Preparing perovskite light emitting diodes (PeLEDs) by a solution process leads to inevitable imbalanced carrier injection and solvent erosion, which prevent us from obtaining high-performance PeLEDs. Here, we report a facile method to fabricate green-emitting PeLEDs with double hole transport layers (HTLs) that significantly promote the hole injection and charge balance. To address the problem of solvent erosion, 1,4-dioxane was adopted as the solvent for poly(9-vinylcarbazole) (PVK) and it was cast onto the surface of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,40-(N-(p-butylphenyl))-diphenylamine)] (TFB). At the same time, an orthogonal solvent 1,4-dioxane was employed to improve the surface smoothness of the perovskite film on the double HTLs. The PeLEDs with TFB/PVK double HTLs showed a maximum current efficiency (CE) and an EQE of 53.5 cd A−1 and 12.9%, respectively. The EQE of the device is about 1.7 and 3 times higher than that of the single HTL device with PVK and TFB, respectively. This remarkable improvement is mainly attributed to the cascade-like energy alignment of the double HTLs, which prevents charging in perovskite nanocrystals (NCs). This work offers a new insight into preparing high performance PeLEDs for displays and lighting devices.

The development of atmospheric water generators depends critically on the preparation of hygroscopic materials. In our systematic efforts toward producing porous frameworks for effective humidity reduction, a super hygroscopic material, which was composed of hetero-layered 2D (two-dimensional) metal–organic framework nanosheet composites, has been established. The effective hetero-layered interactions have endowed the material with the functionalities of simultaneous humidity capture and in situ liquefaction, reaching an unprecedented value of water adsorption of over 658% (highest) of its own weight under ambient atmospheric and room-temperature conditions. Outdoor experiments have suggested that the fast water release is triggered by natural sunlight. Compared with classical hygroscopic salts that require plenty of energy input for water release, the present work has provided a promising strategy for developing next-generation hygroscopic materials for humidity-related management and advanced atmospheric water generator systems.

Multispectral photodetection has garnered enormous research interest and has always been challenging to date. Here, we present the realization of an electrically adjusted single-band/dual-band photodetector based on an inorganic lead-free halide Cs3Cu2I5/two-dimensional (2D) PdTe2 multilayer/Ge multiheterostructure. Owing to its unique optical property and distinct carrier transport behaviour, the device can be easily converted from a single-band photodetector operating in the near-infrared (NIR) region to a dual-band photodetector working in both deep-ultraviolet (DUV) and NIR regimes, upon applying a reverse bias voltage. Significantly, the device shows a peak responsivity of ∼694.1 mA W−1 at 1550 nm at zero bias, and maximum responsivity values of ∼744.2 mA W−1 and ∼712.5 mA W−1 at 265 nm and 1550 nm, respectively, at a small reverse bias. This characteristic also endows the photodetector with an excellent DUV/NIR dual-band optical imaging capability. This work will offer a new opportunity for designing high-performance photodetectors with multiple functionalities operating in complicated circumstances.

Herein, FeCo bimetallic organic frameworks (MOFs) with different compositions were fabricated by controlling the initial molar ratio of Fe3+/Co2+ ions. Through a one-step carbonization treatment of FeCo MOFs and the melamine mixture, a series of FeCo nanoalloys encapsulated in bamboo-like N-doped carbon nanotubes (CNTs), entangled with N-doped carbon nanosheet nanocomposites (FexCoy–N–C), were prepared. The FexCoy–N–C materials presented an excellent ORR performance in alkaline medium. X-ray photoelectron spectroscopy (XPS) studies revealed the existence of ORR-active centers, such as Co–Nx, pyridinic-N and graphitic-N, which were responsible for the enhanced ORR activity. Besides, the synergistic coupling between FeCo alloy and N-doped carbon nanotubes favors the enhancement of the electrocatalytic performance. Among FexCoy–N–C electrocatalysts, the optimized Fe1Co3–N–C and Fe3Co1–N–C catalysts showed higher ORR performance. In addition, both Fe1Co3–N–C and Fe3Co1–N–C showed superior stability compared to the benchmark commercial Pt/C catalyst.

IASCC of stainless steel has been the most important issue for internals BFBs. The inspection data analysis indicates that there is a closed relation between irradiation fluence and cracked BFBs distribution. Then the nanoindentation and 3DAP tests were carried out to study the hardening and radiation induced segregation (RIS) behaviors of the reactor internals stainless steel specimens irradiated with 6 MeV Xe ions at room temperature. It is indicated that higher irradiation damage will cause more significant hardening and RIS and consequently increase the IASCC susceptibility.

Engineering the preorganization of photoactive units remains a big challenge in solid-state photochemistry research. It is of not only theoretical importance in the construction of topochemical reactions but also technological significance in the fabrication of advanced materials. Here, a cyanostilbene derivative, (Z)-2-(3,5-bis(trifluoromethyl)phenyl)-3-(naphthalen-2-yl) acrylonitrile (BNA), was crystallized into two polymorphs under different conditions. The two crystals, BNA-α and BNA-β, have totally different intra-π-dimer and inter-π-dimer hierarchical architectures on the basis of a very simple monomer, which provides them with distinct reactivities, functions and photoresponsive properties. Firstly, two different types of solid-state [2 + 2] photocycloaddition reaction: (i) a typical olefin–olefin cycloaddition reaction within the symmetric π-dimers of BNA-α and (ii) an unusual olefin-aromatic ring cycloaddition reaction within the offset π-dimers of BNA-β have been observed, respectively. Secondly, the crystal of BNA-α can be bent to 90° without any fracture, exhibiting outstanding flexibility upon UV irradiation, while the reversible photocycloaddition/thermal cleavage process (below 100 °C) accompanied by unique fluorescence changes can be achieved in the crystal of BNA-β. Finally, micro-scale photoactuators and light-writable anti-counterfeiting materials have been successfully fabricated. This work paves a simple way to construct smart materials through a bottom-up way that is realized by manipulating hierarchical architectures in the solid state., Two crystals with different hierarchical architectures are observed based on a single molecule, achieving different types of [2 + 2] photocycloaddition. Finally, controllable photoactuators and light-writable materials are successfully fabricated.

Research on nanocluster transformation has generally focused on stable nanoclusters, while analysis of the structural evolutions of metastable nanoclusters just began to receive attention recently. Herein, we report the structural determination of a metastable Ag27H11(SPhMe2)12(DPPM)6 nanocluster and its spontaneous transformation into a size-reduction Ag8(SPhMe2)8(DPPM)1 nanocluster as well as ligand-exchange-triggered transformation into a size-growth Ag29(SSR)12(DPPM)4 nanocluster. The new structure of Ag27 and its structural transformations hopefully provide some implication to the in-depth understanding of metastable nanoclusters.

Biosensing is of vital importance for advancing public health through monitoring abnormalities in biological systems, which may be potentially associated with certain body dysfunctions. A wide range of luminescent materials have been actively pursued in the fabrication of biosensing platforms, particularly ones that can function in complex biological fluids with high selectivity and sensitivity. Recently, metal-organic frameworks (MOFs) have experienced rapid growth due to their tunable structures, large surface area, and being prone to surface engineering, etc. These virtues endow MOF materials with immense feasibility in the target-oriented construction of sensing platforms for specific applications. In this review, we extrapolated six sensing mechanisms for MOF-based photoluminescent biosensing platforms, including photoelectron transfer (PET), resonance energy transfer (RET), competition absorption (CA), structural transformation (ST), chemical conversion (CC), and quencher detachment (QD). Accordingly, recent progress of MOF-based materials in photoluminescence sensing of biomolecules, biomarkers, drugs, and toxins was highlighted. The objective of this review is to provide readers with an extensive overview of the design and synthesis of MOF materials for photoluminescence biosensing. The challenges and outlook are briefly discussed at the end.

Under the guidance of the ESI-MS result for [TeO6@Ag36(CCtBu)18(tfa)12] (1, tfa = trifluoroacetate), a new 36-nucleus silver-alkynyl cluster substituted by four pentafluorobenzoates, named as [TeO6@Ag36(CCtBu)18(tfa)8(F5PhCO2)4] (2), has been fabricated.

The structural determination of metastable nanoclusters remains challenging, which impedes the in-depth understanding of their structural evolution. Herein, based on a case study of Pd1Au9, we present a "cocrystallization-driven stabilization" approach to stabilize the metastable nanocluster and then determine its atomically precise structure. The [Pd1Au9(TFPP)7Br2]+ nanocluster is unstable in solution and would spontaneously convert to Pd2Au23(TFPP)10Br7. The introduction of Au11(TFPP)7Br3 nanocluster to the crystallization process of [Pd1Au9(TFPP)7Br2]+ gives rise to the cocrystallized Pd1Au9(TFPP)6Br3@Au11(TFPP)7Br3, although the composition of Pd1Au9 changes from [Pd1Au9(TFPP)7Br2]+ to Pd1Au9(TFPP)6Br3 among this cocrystallization. With this approach, the overall structure of the metastable Pd1Au9 has been determined. Owing to the very similar cluster size and surface ligand environment between Au11 and Pd1Au9, the obtained Pd1Au9@Au11 cocrystal exhibits almost the same cell parameters as those of the single crystalized Au11. Overall, the proposed "cocrystallization-driven stabilization" approach hopefully sheds light on the structural determination of more metastable nanoclusters.