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Polymer-based dielectric composites show great potential prospects for applications in energy storage because of the specialty of simultaneously possessing the advantages of fillers and polymer matrices. However, polymer-based composites still have some urgent issues that need to be solved, such as lower breakdown field strength (Eb) than polymers, dielectric mismatch, and the poor interface between the matrix and the filler. Hence, this review provides a systematic summary of recent research advances in improving the energy storage properties of polymer-based composites from several aspects, mainly including polymer matrix types, optimization of filler shapes, surface modification of fillers, and design of multi-layer composite structures. Finally, some existing challenges and future perspectives are outlined and discussed to facilitate the further development of polymer-based composites in the energy storage field. We believe this review will help researchers better understand the current development status of polymer-based composites in the energy storage field, and push it forward to a new research stage. [ABSTRACT FROM AUTHOR]

Featured Application: This study can be used for navigation operations of agricultural equipment or vehicles in farm environments. Due to the limitations of low coverage, high repetition rate, and slow convergence speed of the basic genetic algorithm (GA) in robot complete coverage path planning, the state transition matrix of the Markov chain is introduced to guide individual mutation based on the genetic mutation path planning algorithm, which can improve the quality of population individuals, enhancing the search ability and convergence speed of the genetic algorithm. The proposed improved genetic algorithm is used for complete coverage path planning simulation analysis in different work areas. The analysis results show that compared to traditional genetic algorithms, the improved genetic algorithm proposed in this paper reduces the average path length by 21.8%, the average number of turns by 6 times, the repetition rate by 83.8%, and the coverage rate by 7.76% in 6 different work areas. The results prove that the proposed improved genetic algorithm is applicable in complete coverage path planning. To verify whether the Markov chain genetic algorithm (MCGA) proposed is suitable for agricultural robot path tracking and operation, it was used to plan the path of an actual land parcel. An automatic navigation robot can track the planned path, which can verify the feasibility of the MCGA proposed. [ABSTRACT FROM AUTHOR]

To improve the high‐temperature stability of poly(vinylidene fluoride hexafluoropropylene) P(VDF‐HFP)‐based composite film for its potential application in energy storage, the modified silicon nitride (mSi3N4) nanoparticles are fabricated using silane coupling agent (KH‐570) and introduced into P(VDF‐HFP). When the mass fraction of mSi3N4 is 7.5 wt%, the recoverable energy density (Wrec) of the mSi3N4/ P(VDF‐HFP) composite film reaches to 1.79 J/cm3 under a 125 MV/m electric field, which is 82.7% higher than pure P(VDF‐HFP). Interestingly, the dielectric properties of mSi3N4/P(VDF‐HFP) show a considerable thermal stability at a high‐frequency ranging from −20 to 160°C, providing an effective approach for preparing energy storage composites working for high‐temperature environments. [ABSTRACT FROM AUTHOR]

We present a molecular dynamics simulation method including x‐ray diffractometer pattern calculation, mean square displacement (MSD), and nonbonding energy distribution (NED) to disclose the dependencies of condensed structure on its crystalline process of the poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE)) films. For comparison, the P(VDF‐TrFE) solution is casted into the films, and followed that different thermal processes are performed to fabricate the crystalline states of the films. Simulation and experimental results have good consistency, indicating that high temperature annealing can effectively promote all‐trans β phase in the crystal region of P(VDF‐TrFE). As such, P(VDF‐TrFE) 80/20 mol% annealing at 140°C shows a higher MSD (~27.5 Å2) and a faster reducing rate of NED than that of other films, contributing to a large maximum polarization (Ps) of ~15.5 μC cm−2, high a remnant polarization (Pr) of ~11.8 μC cm−2, and an attractive piezoelectric strain coefficient (d33) of −27.1 pC N−1 under 200 MV m−1, respectively, and providing a reference for the applications of P(VDF‐TrFE) in flexible sensors, actuators, transducers, and so forth. [ABSTRACT FROM AUTHOR]

This study presents an advanced two‐step hot‐pressing process for fabricating the 1‐3 type Pb(ZrTi)O3/poly(vinylidene fluoride‐trifluoroethylene) (PZT/P(VDF‐TrFE)) piezoelectric composite sheets, demonstrating significant potential for nondestructive evaluation and information storage applications. The engineered columnar architecture within these composites induces a two‐phase clamping effect, which, upon polarization, facilitates the elongation of PZT and suppresses its lateral vibrations, thus enhancing the electromechanical coupling effect as verified by COMSOL simulations. A notable dielectric constant of 2200 at 100 Hz and a coupling coefficient of 0.725 was achieved with specific geometric modifications to the PZT/P(VDF‐TrFE) sheets. These findings suggest that P(VDF‐TrFE) as a polymer matrix exceeds the performance of conventional epoxy matrices, offering a novel approach to designing 1‐3 type piezoelectric composites. Highlights: P(VDF‐TrFE) effectively drives the elongation strain of internal PZT columns.COMSOL simulation clarifies the clamping effect of piezoelectric P(VDF‐TrFE).PZT/P(VDF‐TrFE) shows a higher kt of 0.725 than that of pure PZT samples. [ABSTRACT FROM AUTHOR]

Wearable electrochemical sensors, which can track various biomarkers in real‐time, is one of the most promising bioanalytical devices in the point of care testing and health management. Sample collection modules, as the important front‐end of the sensors, capture and transfer enough sample so as to achieve real‐time, precise and accurate detection. Noninvasive and minimally invasive techniques for sample collection are highly desired. However, it is still a key challenge to realize a reliable sample acquisition. Herein, we provide an overview on the progress in the sample collection methods for wearable electrochemical sensors. It covers the conventional and emerging methods/structures including reverse iontophoresis, microneedles, as well as microfluidic chips. The working principle, fabrication materials and manufacturing technologies will be introduced in detail. Finally, the present challenges and the development trend in the future of these approaches are also put forward. [ABSTRACT FROM AUTHOR]

A group of (0.65Bi0.5Na0.5–0.35Bi0.2Sr0.7)(Ti1−x,Zrx)O3 (BNBS-(Ti1−x,Zrx)) lead-free energy storage ceramic sheets are prepared by a conventional solid-state sintering method. We find that B-site doping of ZrO2 may minimize the grain size while not change the perovskite structure of BNBS-(Ti1−x,Zrx). As such, BNBS-(Ti1−x,Zrx) possesses the uniform grains and clear grain boundaries, resulting in a high dielectric permittivity (εr) of about 2080 and a low dielectric loss (tanδ) of 0.05 at 100 Hz. Due to the lattice distortion caused by Zr4+ entering the TiO6 octahedral lattice, Tm of BNBS-(Ti1−x,Zrx) decreases with the increase of ZrO2 doping content. Attractively, BNBS-(Ti1−x,Zrx) exhibits relatively slender polarization-electric field (P-E) loops at a high electric field of 100 kV/cm, and BNBS-(Ti0.97,Zr0.03) achieves considerable recycle discharging energy density (Wrec) of 1.47 J/cm3 and high efficiency (η) of 86.94%. Thus, as a block ceramic synthesized by convenient process, this result is superior to most of similar BNT-based materials, and may provide a reference for pulse power capacitors. [ABSTRACT FROM AUTHOR]

Background: Cuproptosis-related gene and long non-coding RNA (lncRNA) modulation of cancer regulation is well-established. This investigation aimed to elucidate the prognostic implications of cuproptosis-associated lncRNAs in muscle-invasive bladder cancer (MIBC).Methods: Employing the Cancer Genome Atlas (TCGA) and IMvigor210 cohorts, bioinformatics and statistical analyses probed the prognostic relevance of cuproptosis-related lncRNAs.Results: Co-expression analysis revealed tight associations between lncRNA expression and cuproptosis-linked genes, with 13 cuproptosis-related lncRNAs found to correlate with MIBC prognosis. Lasso regression identified a six-lncRNA prognostic signature, enabling patient stratification into high- and low-risk categories. Tissue validation substantiated differential expression of FAM13A-AS1, GHRLOS, LINC00456, OPA1-AS1, RAP2C-AS1, and UBE2Q1-AS1 between MIBC tumor and normal tissues. Comparative analyses of tumor microenvironments and immune profiles between risk groups disclosed elevated immunosuppressive molecule expression, including programmed cell death-1 (PD-L1) and T-cell immunoglobulin-3 (TIM-3), in high-risk individuals.Conclusion: These findings suggest that cuproptosis-related lncRNAs may modulate the expression of immunosuppressive molecules, thereby influencing MIBC tumorigenesis and progression. Further exploration is warranted to unveil novel therapeutic targets for MIBC based on the expression patterns of cuproptosis-related lncRNAs and their impact on immune responses in the tumor microenvironment. [ABSTRACT FROM AUTHOR]

A lead‐free tetragonal‐phase (Ba0.94Ca0.06)(Ti0.95Zr0.05)O3 (BCTZ) micro sheet is prepared by molten‐salt growth method, which exhibits a polarizing behavior of relaxor ferroelectricity and possesses a high dielectric constant (εr) of ~2400. Subsequently, the BCTZ sheet is evenly doped into ferroelectric copolymer P(VDF‐TrFE)55/45 mol% with different mass fractions, and the flexible BCTZ/P(VDF‐TrFE) composite films are prepared using a conventional solution casting process. εr of BCTZ/P(VDF‐TrFE) increases with the mass content of BCTZ, and reaches 23.8 in 20 wt% BCTZ sample. Meanwhile, at a high electrical field of 30 MV/m, the strain and electric field of BCTZ/P(VDF‐TrFE) are in the opposite direction, indicating a negative value of piezoelectric strain coefficient (d33) caused by inverse piezoelectric effect. In addition, d33 of different BCTZ/P(VDF‐TrFE) films are fitted using a strain‐electrical field curve, which firstly increases and then decreases with increases in BCTZ content. As such, a high d33 of −47.3 pC/N is obtained in BCTZ/P(VDF‐TrFE)15/85 wt% film. Thus, this research concerning the inverse piezoelectric effect may provide a reference for designing a piezoelectric composite using in transducers and actuators. [ABSTRACT FROM AUTHOR]

In order to improve the energy storage performance of Bi-based lead-free ceramics in dielectric capacitors, K0.5Bi0.5TiO3 is doped into Bi0.5Na0.5TiO3-Bi0.2Sr0.7TiO3 (NBT-SBT) ceramics. We find that NBT-SBT-xK0.5Bi0.5TiO3 (NBT-SBT-xBKT, x=0, 0.02, 0.03, 0.05 and 0.08) ceramic sheets maintain the perfect pure perovskite structures and show the character of relaxor ferroelectrics, indicating that the doped K+ ions smoothly infiltrate into the host lattice of binary system NBT-SBT ceramics and then disturb the long-range order of ferroelectric material and cause the lattice deformation in NBT-SBT. As such, the NBT-SBT-0.03BKT ceramic sample obtains dielectric constant (εr) of 1736, dielectric loss (tanδ) of 0.05, and energy storage efficiency (η) of 70.7%, respectively. More strikingly, NBT-SBT-xBKT ceramics exhibit excellent temperature stability, which helps to store energy at high temperatures. This paper can provide an effective method for manufacturing ceramic based capacitors with high energy storage property. [ABSTRACT FROM AUTHOR]

A group of ferroelectric polyvinylidene‐trifluoroethylene (P(VDF‐TrFE)) with 6, 9, 20, and 50 mol% trifluoroethylene (TrFE) is synthesized by an hydrogenation process using a new catalyst (SiMe3)3SiH from polyvinylidene‐chlorotrifluoroethylene. We find the crystalline region of hydrogenated P(VDF‐TrFE) 80/20 mol% is β crystal phase predominant, which is responsible to the favorable ferroelectric property. Moreover, polyvinylidene fluoride (PVDF) blending is used to fabricate the ferroelectric and relaxor ferroelectric properties of P(VDF‐TrFE) 80/20 mol%. Interestingly, with the increasing of PVDF content, PVDF/P(VDF‐TrFE) has three successional conversion stages of ferroelectricity, antiferroelectricity, and relaxor ferroelectricity, respectively, indicating that the β crystal domains in hydrogenated P(VDF‐TrFE) films gradually reduces with the introduction of PVDF. Otherwise, after an unidirectional stretching process, the ferroelectricity of relaxor PVDF/P(VDF‐TrFE) blend film is reformed. As such, the maximum polarization (Pm) and remnant polarization (Pr) of stretched PVDF/P(VDF‐TrFE) with 90 wt% PVDF reached to 13.8 and 7.5 μC/cm2 under 200 MV/m, respectively. Thus, the three methods proposed in this work including fabricating configuration by changing TrFE content, physical blending by introduction of PVDF, and simple stretching can modify the ferroelectric performances of this hydrogenated P(VDF‐TrFE), which also provides a reference of application of this polymer on ferroelectric areas. [ABSTRACT FROM AUTHOR]