YAG:Ce-Al2O3 composite phosphor ceramics exhibit exceptional thermal and optical properties, demonstrating remarkable resistance to high-power laser excitation and highly promising for laser-driven solid-state lighting. However, due to limitations in understanding the effects of raw materials, fabricating densely structured and homogeneously distributed composite ceramics via tape casting remains a significant challenge. In this study, we investigated effects of particle size and content of raw powders on rheological properties of slurry, microstructure and optical properties of composite phosphor ceramics. The YAG:Ce-70 wt% Al2O3 composite phosphor ceramic, prepared by using nano-sized Y2O3 and Al2O3, showed fully densified and homogeneous microstructure and demonstrated optimal optical properties. Under excitation at a blue laser power density of 21.20 W center dot mm- 2, the YAG:Ce-70 wt% Al2O3 ceramic with a thickness of 0.2 mm created white light with a luminous flux of 1496.05 lm and 141.14 lm center dot W-1. This work paves an avenue to large-scale production of high-performance phosphor ceramics.

ZrO2-substituted (Mg1/6Nb1/3)Ti0.5O2 ceramics, formulated as (Mg1/6Nb1/3)Ti(0.5−x)ZrxO2 (MNZxT(0.5−x), x = 0–0.20), were synthesized using conventional solid-state reaction to investigate their sintering behavior, crystal structure, and microwave dielectric properties. X-ray diffraction (XRD) analysis revealed a rutile-type phase (space group P42/mnm) for x = 0, which gradually transformed into an orthorhombic phase (space group Pbcn) with increasing ZrO2 content, completing the transition at x = 0.16. This study complements the ZrO2-TiO2-MgNb2O6 ternary ceramic system and provides an effective strategy for tuning the dielectric properties of (Mg1/6Nb1/3)Ti0.5O2-based ceramics. Moreover, the sample with x = 0.13, sintered at 1250°C for 3 h, exhibited excellent microwave dielectric properties, including εr = 39, Q×f = 34,000 GHz (at 6.285 GHz), and τf = −5 ppm/°C, which were attributed to improved densification and phase stability. In particular, the (Mg1/6Nb1/3)Ti0.37Zr0.13O2 ceramic dielectric resonator antenna fabricated at 1250°C for 3 h resonated at 6.65 GHz (S11 = −33.4 dB) with a bandwidth of 170 MHz, demonstrating it as a potential candidate for millimeter-wave communication applications.

E-skins capable of multimodal perception are essential for intelligent human-machine interaction, yet integrating real-time responsiveness with structural self-healing across multiple sensing modalities remains a significant challenge. Here, we report a biologically inspired, self-healing e-skin that enables the perception of tactile, pressure, nociceptive, and thermal stimuli. The device adopts a vertically stacked compact architecture comprising double-network cross-linked polymer layers and eutectic liquid metal layers, enabling rapid and complete structural healing even after severe mechanical damage over a wide temperature range. We demonstrate that the e-skin retains its functional integrity after healing, with triboelectric and capacitive sensing units enabling high-sensitivity, spatiotemporally resolved tracking of tactile and pressure stimuli, respectively. Meanwhile, by quantitatively analyzing the mechanoluminescent and thermochromic spectra, the optical waveguide sensing units enable real-time optical encoding of nociceptive and thermal stimuli, thereby allowing effective classification of impact and burn injury risks. Our work lays a solid foundation for the development of intelligent robotic systems capable of adaptive perception and injury prevention in complex and dynamic human-machine environments.

The rational selection of green biomass precursors and the development of efficient activation strategies are critical for the advancement of sustainable energy storage electrode materials. This study employed waste chrysanthemum stems as renewable precursors to fabricate porous carbons via a two-step method involving high-temperature carbonization followed by KOH activation. The optimized CSPC-2 possesses a large specific surface area (SSA, 1710.8 m2 g-1) and a high specific capacitance (366.5 F g-1 at 0.5 A g-1). Liquid-state symmetric supercapacitors (SCs) assembled with 1 M Na2SO4 electrolyte achieve an energy density of 27.4 Wh kg-1 at 425 W kg-1. Meanwhile, all-solid-state SCs fabricated with a PVA/KOH gel electrolyte exhibit a wide voltage window (0-1.3 V), a high specific capacitance (318.8 F g-1), and a superior energy density (18.7 Wh kg-1 at 325 W kg-1). The solid-state device retains 88.9 % of its initial capacitance after 10,000 cycles and demonstrates excellent electrochemical performance in bending tests and series-parallel configurations. These results indicate the potential of chrysanthemum stem-derived porous carbons as low-cost, eco-friendly electrode materials for high-energy-density SCs, providing a viable strategy for sustainable biomass utilization in energy storage applications.

Given increasing environmental protection requirements, the development of lead-free piezoceramics with giant electro-strains is crucial for advancing the next generation of piezoelectric actuators. Defect engineering is considered a powerful measure to enhance the electro-strain of piezoceramics which is key factor for piezoelectric actuators. In this paper, Al3+ ions as acceptor dopant ions were introduced into (K0.5Na0.5)NbO3 ceramics for enhancing properties and the composition, crystal structure, and electrical performance of the doped ceramics were investigated. The results show that KNN-based piezoelectric ceramics suitably doped with Al3+ ions exhibit giant electro-strain of 0.73 % and high inverse piezoelectric coefficient values (d(33)& lowast;similar to 1849 p.m./V). This study demonstrates that Al is a suitable acceptor dopant for KNN-based ceramics and can effectively form defective dipoles, which in turn affects domain switching, significantly enhancing electro-strain.

Cryogenic anti-counterfeiting technology is essential to ensure safety and effectiveness in fields such as medical refrigeration, cold chain transport, and cryogenic bioengineering. This study proposes a low-temperature multimodal anti-counterfeiting strategy based on the distinct photoluminescence (PL) behaviors of pure CsCdBr3 and CsCdBr3: 4 % Pb2+ metal halide perovskites. The host CsCdBr3 exhibits orange self-trapped exciton (STE) emission peaking at 630 nm at cryogenic temperatures, which is thermally quenched at room temperature (RT). Incorporation of Pb2+ ions result in additional ultraviolet and green emission bands, enabling excitation-wavelength-dependent color modulation from orange to green by modulating the excitation from 300 to 400 nm. Moreover, CsCdBr3: 4 % Pb2+ exhibits temperature-dependent PL color from green to oranges by increasing the temperature from 80 to 300 K. Leveraging these excitation and temperature-responsive synergy, we developed a multi-modal anti-counterfeiting platform for cold chain transportation. This work highlights the promising potential of CsCdBr3: 4 % Pb2+ phosphors as innovative materials for low-temperature multimode anti-counterfeiting technologies.

TGAG:Ce ceramics show great potential for applications in laser - driven white lighting sources. However, the fabrication of large - size and dense TGAG:Ce ceramics with low cost remains a challenge for commercialization. In this study, tape casting was employed to prepare large - size TGAG:Ce green tapes. The molding conditions and sintering temperature were systematically investigated. The slurry demonstrated optimal rheological and mechanical properties with a formulation of 2 g PEI, 16 g PVB, and an R value (the ratio of plasticizer to binder) of 0.3. The TGAG:Ce phosphor ceramic, sintered at 1700.C for 5 h, demonstrated a luminous efficacy of 266.25 lm center dot W-1 and a high luminance of 665.61 Mcd m(-2) under blue laser irradiation.

The excessive consumption of alkali during biomass-derived porous carbon production leads to environmental pollution. To achieve the goals of green and sustainable development in energy and carbon neutrality, this work presents an efficient synthesis of porous carbon materials using broad bean husk (BBH) as a precursor via hydrothermal pretreatment with CH3COOH and activation with K2CO3. The optimized BBHPC-2 possesses a welldeveloped pore structure and a remarkable specific surface area (SSA) of 2078.4 m2 g- 1, exhibiting a specific capacitance of 386.5 F g- 1 at 0.5 A g- 1. The BBHPC-2-based symmetric supercapacitor delivers an exceptional energy density of 28.4 Wh kg- 1 at a power density of 425.0 W kg- 1 in 1 M Na2SO4 electrolyte, while retaining 90 % of its initial capacitance after 5000 cycles. Furthermore, the symmetric all-solid-state supercapacitor assembled with a PVA-KOH gel electrolyte delivers an energy density of 12.2 Wh kg- 1 at a power density of 275.0 W kg- 1. The device demonstrates excellent integrability and practical application potential in seriesparallel and lamp-lighting tests. This study proposes an innovative, controllable synthesis strategy for biomass-derived carbon materials, establishing a reference for applying multi-activation synergistic approaches in the preparation of novel carbon materials.

The investigation of green carbon precursors and cost-effective activators has become an important area for manufacturing electrode materials. Bamboo shoot shells are carbonized at high temperatures and then dual activated with KOH and K2CO3 to create bamboo shoot shell-based porous carbon materials (BSC-X). The obtained porous carbon materials are subjected to electrochemical tests, nitrogen adsorption and desorption (BET), scanning electron microscopy (SEM) and infrared and X-ray diffraction (XRD) analyses. The experimental results show that the BSC-1 porous carbon has a rich pore structure, high specific surface area (2583.75 m2 g-1), O content of up to 33.00 % and total pore volume of up to 1.47 cm3 g- 1. In the three-electrode test system, the BSC1 shows the specific capacitance of 459.50 F g- 1 at 0.5 A g- 1, a capacitance retention of 73.48 % at a current density of 10 A g-1, and a capacitance retention of 99.97 % and a Coulombic efficiency of 94.85 % after 10,000 cycles at a current density of 10 A g-1. The symmetric supercapacitor assembled with BSC-1//BSC-1 exhibits a voltage range of 0-2.0 V in 1 M Na2SO4 electrolyte, the specific capacitance of 313.00 F g- 1 (at 0.5 A g- 1), and a high energy density of up to 43.47 Wh kg-1. The capacitance retention of 94.34 % and the Coulombic efficiency is 94.72 % after 10,000 cycles at 10 A g- 1 current density. The supercapacitors with PVA/KOH gel as electrolyte have a specific capacitance of 252.57 F g- 1 and a high energy density of up to 17.19 Wh kg- 1 at a voltage of 0-1.4 V and a current density of 0.5 A g-1. The capacitance retention of 85.45 % and Coulombic efficiency of 92.37 % after 10,000 cycles at 10 A g- 1 current density. This study provides an affordable and renewable strategy for the synthesis of porous carbon materials for supercapacitors.

The structural‐functional integrated device optimizes the synergy between mechanical strength and functionality through advanced material design, offering broad application potential. In this work, a novel structural‐functional integrated device designed to address the challenge of stress monitoring in fiber‐reinforced composites is presented. By incorporating potassium sodium niobate piezoelectric material into carbon fiber‐reinforced polymer composites, a load‐bearing and piezoelectric integrated device is successfully developed. The device exhibits outstanding flexural strength of 377.7 MPa and a flexural modulus of 18.8 GPa, making it suitable for use as a structural material. Simultaneously, the device possesses intrinsic piezoelectric properties and can function as a mechanical sensor, demonstrating a linear voltage output over an exceptionally wide pressure range from 10 to 3.8 × 10⁴ N, which enables the monitoring of mechanical stress in the device. Through a carefully designed pattern of carbon fiber fabric, the device can also intelligently identify the location and magnitude of the applied pressure. This research achieves the integration of high mechanical strength and stress sensing functionality through material design, opening new avenues for the development and application of smart composite materials.

Maintaining the power conversion efficiency (PCE) of flexible perovskite solar cells (fPSCs) while decreasing their weight is essential to utilize their lightweight and flexibility as much as possible for commercialization. Strengthening the interfaces between functional layers, such as flexible substrates, charge transport layers, and perovskite active layers, is critical to addressing the issue. Herein, we propose a feasible and one-stone-for-two-birds method to improve the electron transport layer (ETL), SnO2, and the interface between the ETL and perovskite layer simultaneously. In detail, poly(acrylate ammonium) (PAAm), a low-cost polymer with a long chain structure, is added into the SnO2 aqueous solution to reduce the aggregation of SnO2 nanoparticles, resulting in the deposition of a conformal and high-quality ETL film on the tin-doped indium oxide film surface. Simultaneously, PAAm addition can effectively regulate the crystallization of the perovskite films, strengthening the interface between the SnO2 film and the buried surface of the perovskite layer. The outstanding PCEs of 22.41% on small-scale fPSCs and 18.54% on fPSC mini-modules are among the state-of-the-art n-i-p type fPSCs. Moreover, the fPSC mini-module on the 20 mu m-thick flexible substrate shows a comparable PCE with that of the fPSC mini-module on the 125 mu m-thick flexible substrate, exhibiting a high power-to-weight of 5.097 W/g. This work provides an easy but essential direction for further applications of fPSCs in diverse scenarios.

The composition of materials can significantly affect the structure and properties of KNN based piezoelectric ceramics. Here, 0.965(K0.48Na0.52)(Nb0.95Sb0.05)O3-0.035Bi0.5(Na0.3K0.3Li(0.4-x)Bax)0.5ZrO3 ceramics were designed and synthesized using CuO as a sintering aid to promote densification of ceramics. The results show that these ceramics had orthorhombic-tetragonal phase transition structure, and the ratio of the two phases becomes an important factor affecting the electrical properties. When the ratio of the two is close, the piezoelectric performance is optimized. Under specific composition, the sample exhibits a large piezoelectric effect, with the piezoelectric constant and inverse piezoelectric constant reaching 347 pC/N and 1052 p.m./V, respectively. These results prove that rational composition and structure modulation can effectively improve the performance of KNN-based lead-free piezoelectric ceramics, making it a promising alternative for lead-based piezoelectric ceramic materials.

Mechanoluminescence (ML) sensing technologies open up new opportunities for intelligent sensors, self-powered displays and wearable devices. However, the emission efficiency of ML materials reported so far still fails to meet the growing application requirements due to the insufficiently understood mechano-to-photon conversion mechanism. Herein, we propose to quantify the ability of different phases to gain or lose electrons under friction (defined as triboelectric series), and reveal that the inorganic-organic interfacial triboelectricity is a key factor in determining the ML in inorganic-organic composites. A positive correlation between the difference in triboelectric series and the ML intensity is established in a series of composites, and a 20-fold increase in ML intensity is finally obtained by selecting an appropriate inorganic-organic combination. The interfacial triboelectricity-regulated ML is further demonstrated in multi-interface systems that include an inorganic phosphor-organic matrix and organic matrix-force applicator interfaces, and again confirmed by self-oxidization and reduction of emission centers under continuous mechanical stimulus. This work not only gives direct experimental evidences for the underlying mechanism of ML, but also provides guidelines for rationally designing high-efficiency ML materials.

Developing a new generation of increased energy, stability, and easily applicable N-rich energetic materials to replace RDX and HMX has posed significant challenges over the past decade. This work presents the design and synthesis of a series of novel N-rich energetic materials (N1 to N3 series) based on the triazole-tetrazole system. Among these, the N3 series demonstrates exceptional detonation performance and stability. It is noteworthy that the N3-3 molecule has achieved the best overall performance among N-rich energetic materials, with an onset decomposition temperature of 302 degrees C and a detonation velocity of 9341 m s-1, which significantly surpasses that of HMX. Additionally, structural studies of the N1 molecule reveal that the positioning effect of the nitro group and steric hindrance within the molecule disrupt the planar characteristics of the triazole-tetrazole system. In contrast, the amino group in the N3 series enhances molecular planarity, facilitating the formation of large conjugated systems and extensive hydrogen bond networks in N-rich energetic materials. This approach effectively enhances the stability of energetic material molecules and offers valuable insights for the development and design of stable N-rich energetic compounds.

Rapid development and evolution are needed in the era of information human wearable sensors for the data collection basis of the Internet of Things. To deal with the issues of poor flexibility in the existing sensing schemes, as well as the inability of devices to self-heal, we synthesized a silicone self-healing material-PP3, which could serve as a flexible substrate for wearable sensors. The fracture stress of this material is 0.34 MPa, with a record elongation at break of up to 290%; its self-healing efficiency can reach more than 80% after 12 h of repair at room temperature. We printed liquid metal based on gallium as the flexible circuit over the PP3 substrate by modifying the surface of the substrate. Here, based on the self-healing property of PP3 and the fluidity of liquid metal, we realize triboelectric sensors with overall self-healing capability able to monitor pressure in the range of 5180 kPa; their maximum sensitivity reaches 0.9/kPa under low pressure, and good stability is maintained for the triboelectric sensors after 400-cycle tests.

Tactile sensors play a critical role in the Internet of Things (IoT) and wearable devices. However, although current tactile sensors can precisely measure pressure, the simple fabrication of stretchable high-performance tactile sensors with a broad measuring range and multifunctions is still challenging. Herein, an ink-direct writing 3D printing method is developed to fabricate novel stretchable dual-mode tactile sensors with coaxial fiber structure. The 3D printed coaxial fibers have an outer skin composed of silicone rubber and polytetrafluoroethylene micropowders thixotropic agent and an inner core of an ionic conductive solution composed of polyvinyl alcohol and sodium chloride. The coaxial fibers exhibit excellent electrical conductivity (0.54Scm−1) and outstanding stretchability, as high as 390%. The intersection of the two fibers constitutes a dual-mode tactile sensor which can operate in triboelectric or capacitive modes with complementary measurement ranges from 0.0003 to 0.4517N. Besides, by combining the signals from the two modes, the sensor can identify the material that comes into contact with the sensor. A 3D printed network of tactile sensor arrays made of warp-weft interwoven coaxial fibers is able to accurately detect the locations of multi-point contact with the array. This dual-mode multifunctional tactile sensor can be widely used in various applications such as the IoT and wearable devices.

Alumina and 304 stainless steel were brazed with silver-copper-titanium filler+copper foil. The effect of adding copper foil to the filler on the microstructure of the alumina/304 joint was studied, and the reasons for the effect of adding copper foil with different thicknesses on the joint performance were also analyzed. The standard microstructure of alumina/304 joint with silver-copper-titanium+copper foil filler is alumina ceramic/copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) continuous layer+copper titanide (TiCu)/silver solid solution+copper solid solution/titanium compound with iron (1 : 2) (TiFe2)+iron-chromium compound/304 stainless steel. The added copper foil inhibits the diffusion of titanium elements, thereby reducing the formation of the brittle copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) and alleviating the residual stress. In addition, after adding copper foil, the copper solid solution is distributed in blocks in the joint, which also improves the plastic deformation ability of the joint. Under the synergistic effect of these two effects after adding copper foil, the joint strength is improved. When the copper foil was 200 mu m, the shear strength is 198.10 MPa. Alumina ceramic and 304 stainless steel were brazed using silver-copper-titanium+copper foil filler. The effect of copper thickness on the microstructure and properties of the joint was studied. The thickness of copper were 50 mu m, 100 mu m, 150 mu m, 200 mu m and 300 mu m. When the copper thickness is 200 mu m, the shear strength of the joint reaches 198.10 MPa.image

Nickel oxide (NiOx) nanocrystals have been widely used in inverted (p-i-n) flexible perovskite solar cells (fPSCs) due to their remarkable advantages of low cost and outstanding stability. However, anion and cation impurities such as NO3- widely exist in the NiOx nanocrystals obtained from calcinated nickel hydroxide (Ni(OH)2). The impurities impair the photovoltaic performance of fPSCs. In this work, we report a facile but effective way to reduce the impurities within the NiOx nanocrystals by regulating the Ni(OH)2 crystal phase. We add different alkalis, such as organic ammonium hydroxide and alkali metal hydroxides, to nickel nitrate solutions to precipitate layered Ni(OH)2 with different crystalline phase compositions (α and β mixtures). Especially, Ni(OH)2 with a high β-phase content (such as from KOH) has a narrower crystal plane spacing, resulting in fewer residual impurity ions. Thus, the NiOx nanocrystals, by calcinating the Ni(OH)x with excess β phase from KOH, show improved performance in inverted fPSCs. A champion power conversion efficiency (PCE) of 20.42% has been achieved, which is among the state-of-art inverted fPSCs based on the NiOx hole transport material. Moreover, the reduced impurities are beneficial for enhancing the fPSCs' stability. This work provides an essential but facile strategy for developing high-performance inverted fPSCs.

AbstractAlumina and 304 stainless steel were brazed with silver‐copper‐titanium filler+copper foil. The effect of adding copper foil to the filler on the microstructure of the alumina/304 joint was studied, and the reasons for the effect of adding copper foil with different thicknesses on the joint performance were also analyzed. The standard microstructure of alumina/304 joint with silver‐copper‐titanium+copper foil filler is alumina ceramic/copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) continuous layer+copper titanide (TiCu)/silver solid solution+copper solid solution/titanium compound with iron (1 : 2) (TiFe2)+iron‐chromium compound/304 stainless steel. The added copper foil inhibits the diffusion of titanium elements, thereby reducing the formation of the brittle copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) and alleviating the residual stress. In addition, after adding copper foil, the copper solid solution is distributed in blocks in the joint, which also improves the plastic deformation ability of the joint. Under the synergistic effect of these two effects after adding copper foil, the joint strength is improved. When the copper foil was 200 μm, the shear strength is 198.10 MPa.