To meet the demands of miniaturization and integration in modern electronic packaging, developing materials with low coefficient of thermal expansion (CTE) is essential to reduce thermal stress and enhance device reliability. In this study, the dense negative thermal expansion ceramic ScF₃ was prepared with a CTE of -8.86 × 10^-6/℃. The ScF₃ ceramic was cold sintered at 150 ^℃, exhibiting a low permittivity of 5.3 and a high quality factor (Q×f) of 14,700 GHz. By incorporating ScF₃ to the hexagonal boron nitride (BN) ceramic, the CTE of ScF₃-BN composite ceramic was adjusted to 3.36 × 10^-6/℃, establishing compatibility with silicon-based chips. And finite element simulations verified that ScF₃-BN composite significantly reduces thermal stress compared to Li₂MoO₄ or Al₂O₃ ceramics. Furthermore, this work demonstrates the potential of cold-sintered ScF₃ to regulate thermal expansion in packaging substrates, paving the way for improved performance in next-generation electronic devices.

Lithium-sulfur batteries (LSBs) exhibit high energy density and high theoretical specific capacity, approximately one order of magnitude higher than traditional lithium-ion batteries. However, the shuttling effect of lithium polysulfides (LiPSs) generated during the charge-discharge process severely compromises battery performance and hinders commercialization. In this paper, a 3D porous carbon gel sulfur host, M@rGO-PCG (M = Ni, Co), composed of transition metal particles and redox graphene, was fabricated through gelation and freeze-drying techniques. This material enhances the conductivity of the cathode, buffers the volume expansion of the electrode, and further accelerates the catalytic conversion of LiPSs. The assembled Ni@rGO-PCG/S and Co@rGO-PCG/S batteries deliver initial discharge specific capacities of 1390.0 mA·h·g^-1 and 1603.6 mA·h·g^-1 at a current rate of 0.1C, respectively. The findings provide valuable insights into the synergistic suppression of the shuttling effect through multiple functions.

Ultra-high temperature ceramics (UHTCs) exhibit ultra-high melting points and relatively high mechanical performance, making them ideal coating materials for extreme environment applications like hypersonic vehicles. Recently, novel design strategies of UHTCs coatings have been proposed, mainly including the composition and structural design. In this article, state-of-the-art approaches including multilayer and gradient UHTC coatings for enhanced mechanical and ablation resistance, surface engineering for the improvement of coating adhesion, materials and microstructural design for thermal insulation, laser ablation protection, and drag reduction were reviewed. Furthermore, advanced designing and fabrication techniques for UHTC coatings are also prospected, which can provide insights for the development of next-generation multi-functional UHTC coatings for harsh conditions.

The advancement of communication technologies demands dielectric materials with superior performance characteristics, particularly low permittivity and minimal dielectric loss. This study investigates Ge⁴⁺-substituted willemite ceramics, including Zn₂Si_1-xGe_xO₄ (ZS-xGe, x=0 and 0.1) and Zn_1.8Si_1-yGe_yO_3.8 (ZS-yGe, y=0 to 0.3), synthesized via the conventional solid-state method. The non-stoichiometric design effectively suppresses the formation of ZnO. The intrinsic and extrinsic losses of the ZS-xGe ceramics are separated by a systematic comparative analysis of the dielectric losses in the terahertz band, and the extrinsic losses are fitted by the Drude term in the Lorentz-Drude dielectric response model. Consequently, ZS-yGe ceramics exhibit lower ε_r and significantly improved Q×f values across microwave to terahertz band. In ZnO-free ceramics, Ge⁴⁺ substitution enhances the ionic polarizability, the unit cell volume and the bond strain, increasing ε_r and Q×f values (decreasing intrinsic losses), and decreasing τ_f. The optimized Zn_1.8Si_0.9Ge_0.1O_3.8 ceramics demonstrate superior dielectric properties with ε_r = 6.66, Q×f = 225,500 GHz and τ_f = -60.0 × 10^-6℃^-1 at 12.45 GHz, and ε_r = 7.02, Q×f = 401,800 GHz at 1 THz. These novel ceramics are positioned as promising candidates for next-generation microwave and terahertz communication devices.

Over the past decade, the field of high-entropy ceramics (HECs) has expanded rapidly to encompass a broad range of oxides, borides, silicides, and other ceramic solid solutions. In 2020, we proposed extending HECs to compositionally complex ceramics (CCCs), where non-equimolar compositions and the presence of long- or short-range order, although reducing configurational entropy, create new opportunities to tailor and enhance properties, often surpassing those of higher-entropy counterparts. Along these lines, several fundamental scientific questions arise. Is the entropy in HECs truly high? Is maximizing entropy always desirable? In this perspective article, I revisit key concepts and terminologies and highlight emerging directions, including dual-phase CCCs, ultrahigh-entropy phases, and novel processing routes such as ultrafast reactive sintering. I propose that exploring compositional complexity across vast non-equimolar spaces, together with exploiting correlated disorder (coupled chemical and structural short-range order), represents a transformative strategy for designing ceramics with superior performance.

Flexible and transparent strain sensors with high sensitivity were fabricated by embedding hybrid networks of carbon nanotubes (CNTs) and carbon (C) nanoparticles into micro-mesh polydimethylsiloxane (PDMS) substrates. The resulting devices exhibited optical transmittance above 70% and haze below 7%, ensuring unobtrusive integration on skin. Systematic variation of CNT:C ratios (0:1, 1:1, 2:1, 3:1) revealed that the 2:1 hybrid achieved optimal performance, combining uniform dispersion, strong interfacial adhesion, and robust conductive pathways. The optimized device (S2-PDMS) demonstrated a maximum gauge factor of 465.35 at 32.5% strain, and reliable cycling stability for repeatability of stretching, bending, and twisting deformations. Mechanical tests confirmed high tensile strength (2.63 MPa) and durability under repeated deformation, outperforming polyethylene terephthalate (PET)-based counterparts. The sensor also exhibited response times in the range of~158-557 ms and recovery times between ~110 ms and 697 ms, depending on the type and complexity of the human motion. As such, the sensors successfully monitored diverse human motions, subtle muscle activity, and vocal vibrations, and enabled wireless data transmission via Bluetooth, underscoring their potential for real-time health monitoring, human-machine interfaces, and Internet of Things-enabled wearable electronics.

In this work, Mn_xZn_1-xFe₂O₄ (MZF) ferrite and MXene (Ti₃C₂T_x) composites were addressed to enhance the electrochemical performance. MXene is a relatively new material belonging to the 2D layered family and is mainly used to enhance the electrochemical features of electrode materials. The incorporation of MZF material acts as a conductive bridge, affecting the structural stability and electrochemical features of Ti₃C₂T_x MXene. MZF nanoparticles were embedded with Ti₃C₂T_x MXene to develop a hybrid MXene@MZF₁ electrode composite. The structural formation of composites was investigated using Raman spectroscopy, XRD, SEM, EDX, TEM, and XPS. The electrochemical examination of the prepared composite revealed a significant increase in specific capacitance. The (MXene)₇₅(Mn_0.05Zn_0.95Fe₂O₄)₂5 electrode material was exposed to a gravimetric specific capacitance of 646.9 F/g at a scanning rate of 5 mV/s. Moreover, an asymmetric supercapacitor (ASC) device was constructed, achieving a specific energy of approximately 47 W·h·kg^-1 and a power density of 4937.1 W/kg, respectively. An excellent capacitance retention of 128.9% and coulombic efficiency of 99% were observed after 6000 GCD duty cycles. This study confirmed the good stability of the MXene@MZF₁ electrode compound after experimental and theoretical investigations. Therefore, MXene-based MZF₁ electrode materials enhanced electrochemical properties and improved cyclic durability for the ASC device.

Tuning the structure-activity of fillers and matrix is crucial for designing polymer-based dielectric capacitors with high energy storage performance. Up to date, how the fillers' structural characteristics (surface/interface configurations, dimensions, orientations etc.) contribute to the overall energy storage is far from unveiled. To this end, a combined filler-polymer dual-side design strategy is developed, which involves the DFT guidance for the electronic transport criteria for the designable synthesis of KNb₃O₈ fillers. Four different structural configurations are constructed, which are surface-modified with polydopamine (PDA) to fabricate the final composite films, i.e. PDA@KNb₃O₈/PVDF-P(VDF-HFP)-PMMA with particular orientations and arrangements, through a well-controlled solution casting method. Comprehensive structural and electrical investigations reveal that 1D/2D-orientated PDA@KNb₃O₈ fillers could obviously enhance the breakdown field and energy storage performance. The difference is that the 1D fillers more effectively improve the energy efficiency (up to 72%), while the 2D fillers more steadily achieve high energy density (U_e = 28.35 J/cm³) among the highest U_e reported for the composites. This work not only uncovers the structural origin of the electrostatic storage in inorganic-polymer composite films but also provides critical insights in designing high-energy-density film capacitors.

Digital light processing (DLP) printing of PbZrTiO₃ (PZT) ceramics is significantly hampered by the inherent high light absorption of the powder, leading to detrimental defects such as shrinkage and cracking, which severely compromise the final sensor performance. Herein, we propose a strategy to modulate the light absorption of PZT powder by mixing compositions calcined at different temperatures. By optimizing the mass ratio of P860 to P1150 to 1:9, we achieved a suspension with enhanced curing depth and rheological properties, enabling the fabrication of high-density ceramics with a piezoelectric constant of 470 pC/N. Furthermore, a sophisticated sandwiched piezoelectric sensor, architected with crossed square columns, demonstrated exceptional electromechanical performance, generating an open-circuit voltage of 278 V and a short-circuit current of 2.19 μA. This design conferred a piezoelectric sensitivity approximately 7 times greater than bulk counterparts. Remarkably, despite its compact size of merely 1.3 cm × 1.3 cm, this sensor still achieves a transmission power of 5.2 mW during underwater remote energy transfer over a distance of 400 mm. This work establishes a viable pathway for fabricating next-generation high-performance PZT piezoelectric sensors via advanced DLP processing.

As promising dielectric alternatives to SiO₂, hafnium-based oxides show broad application prospects in integrated circuits, dielectric sensors, and optoelectronics. Nevertheless, stabilizing the T-phase with a high dielectric constant (high-κ) and further improving its κ value remain key challenges for practical applications. Using first-principles calculations, we reveal the dielectric enhancement mechanism in the T-phase HfO₂ by demonstrating that the high-κ primarily originates from the softening of phonon vibration frequencies, which can be effectively tuned by bond length and atomic mass. Furthermore, we find that doping atoms with lower electronegativity form stronger ionic interactions with O atoms, favoring the stabilization of the high-coordination T-phase. Based on these analyses, we propose a general design rule: doping atoms with remarkable size, heavy mass, and small electronegativity could effectively improve high-κ and stabilize the T-phase simultaneously. Guided by this rule, a more promising Ce-doping strategy in HfO₂ than Zr-doping is proposed, which is also supported by some experimental results. This work not only delves into the physical mechanism of the high-κ in hafnium-based oxides, but also provides practical methods to enhance their dielectric constants.