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.

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.

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.

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.

Defect engineering is a key strategy for optimizing the thermoelectric (TE) properties of PbTe-based materials, and investigating charged defects in PbTe grain boundaries (GBs) is crucial for understanding its thermoelectric properties. In this study, focusing the GBs, we perform a high-throughput investigation of the formation energies with various charged point (intrinsic and extrinsic) defects and their effects on the mechanical properties, the shear modulus. The GBs can facilitate the formation of the charged point defects (such as , ), indicating the accumulations of the defects within the GBs region. Such defect accumulation can strongly increase the phonon scatterings. Furthermore, charge defects within Te-PbTe GBs lower the shear modulus to <33.1 GPa, due to the weakening interactions between Pb-Te bonds. The soft bonds around GBs will induce the stronger anharmonicity and further suppress the lattice thermal conductivity. Employing the machine learning method, we establish the relationship between the shear modulus and physical descriptors, which can efficiently screen or design the various purposes of PbTe compounds. Our work bridges the gap in understanding charged defects at grain boundaries in PbTe-based thermoelectric materials and giving rise to the design methodology to achieve high promising thermoelectric performance through charged defect influenced mechanical properties.

In this study, we propose grain boundary engineering and nanostructuring to enhance the thermo-electric performance of SnTe through tri-doping with Mn, Ge, and Bi. The synergistic effects on the band structure were analyzed through DFT calculations and validated through a series of doping experiments with each dopant. The nonstoichiometrically tri-doped sample exhibits a unique microstructure, characterized by Mn-Ge precipitates along the grain boundaries and coherently embedded nanostructures within the matrix. These microstructural features, combined with the effects of each dopant, synergistically enhanced the thermoelectric properties, yielding a maximum zT of 1.32 at 873 K. The thermoelectric generator exhibited a maximum output power of 661 μW at ΔT = 485 K, confirming its viability for mid-temperature thermoelectric applications.

Transparent thermoelectric CdO thin films exhibit critical flexibility and thermoelectric performance that require focused research to advance flexible transparent self-powered devices. Here, we demonstrate the superior flexibility of freestanding single-crystalline CdO membranes. These membranes achieve a notable room-temperature power factor of 1.48 μW·cm^-1·K^-2 and exhibit superior optical transmittance exceeding 94% in the 550-800 nm range. Crucially, freestanding CdO exhibits exceptional mechanical robustness, retaining >90% electrical conductivity after 1000 bending cycles (radius: 11.5 mm). Microstructure analyses confirm polycrystalline CdO films suffer from grain boundary cracking under bending due to stress concentration, but single-crystal CdO membranes-without grain boundaries to concentrate stress-exhibit better flexibility and resistance to cracking. Furthermore, curvature-induced strain boosts the power factor by 12.8%, providing a curvature-controlled strain engineering strategy to optimize flexible thermoelectric performance. This work establishes free-standing CdO as a highly efficient and flexible thermoelectric material and suggests a fundamental strategy for designing robust smart materials for transparent, self-powered flexible electronics.

Aromatic polyimide (PI) with high glass transition temperature (T_g) shows promise as a polymer dielectric for energy storage, but its rigid aromatic structure and electron delocalization cause significant conduction loss, degrading energy storage performance and breakdown strength (E_b) under high temperatures. Herein, we introduce a novel semi-alicyclic fluorinated polyimide (H-FPI) designed via a molecular engineering strategy that synergistically integrates bandgap and topological conformation modulation. Specifically, the alicyclic group elevates the lowest unoccupied molecular orbital (LUMO) while strong electron-withdrawing trifluoromethyl (-CF₃) substitution depresses the highest occupied molecular orbital (HOMO), creating a wide bandgap (4.2 eV). Concurrently, the chair-conformation alicyclic backbone and sterically bulky -CF₃ groups synergistically disrupt molecular planarity, reducing π-orbital overlap to suppress charge transfer while restricting chain mobility to yield a high T_g of 272 ℃. Remarkably, H-FPI film delivers a high energy density of 6.02 J/cm³ with a superior breakdown strength of 626 MV/m at 200 ℃, surpassing commercial PI and fluorinated polyimide (FPI) by 1261% and 55%, respectively. Furthermore, H-FPI film exhibits exceptional capacitor charge-discharge cyclability, enhanced mechanical robustness, and excellent thermal stability. This work establishes a new molecular design paradigm for organic capacitors in electrffied transportation and smart grid systems requiring high-temperature working reliability.

Density Functional Theory (DFT)-derived electronic descriptors are key to accelerating the design of effective ORR/OER catalysts. The O 2p-band center, in particular, is a robust descriptor of catalytic activity in perovskite oxides. This study examines the O 2p-band center in Fe⁴⁺ perovskite-type layered oxides, focusing on the Ruddlesden Popper (RP) phases Sr₂FeO₄ and Sr₃Fe₂O₇, as well as the high-Tc superconductor YSr₂Cu₂FeO₈. The analysis emphasizes trends driven by compositional modifications. The O 2p-band centers of Sr_2-2xLa_2xFeO₄ and Sr_3-3xLa_3xFe₂O₇ (0 < x < 1) correlate linearly with the Fe oxidation state, and span a wide energy range (-1.2 eV to -4.7 eV with PBE+U; -1.9 eV to -4.7 eV with SCAN). Partial substitution of Fe with 3d transition metals (TM) in Sr₂Fe_7/8xM_1/8O₄ shifts the O 2p band center, with the more electronegative TMs bringing it closer to the Fermi level. RP-Sr₂FeO₄ exhibits remarkable tunability of the O 2p-band center, enabling the compositionally driven design of oxygen catalysts with potentially improved activity-stability balance. In contrast, YSr₂Cu₂FeO_7+δ (0 < δ < 1) shows no correlation between the O 2p-band center and Fe oxidation states, likely due to a change in Fe coordination from octahedral (δ = 1) to tetrahedral (δ = 0). The O 2p-center values (-0.9 eV to -1.3 eV with PBE+U; -1.5 eV to -2 eV with SCAN) suggest that YSr₂Cu₂FeO_7+δ could potentially catalyze the ORR/OER, though stability over operation time remains a challenge.

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.