As a pivotal category in the realm of electronics skins, flexible pressure sensors have become a focal point due to their diverse applications such as robotics, aerospace industries, and wearable devices. With the growing demands for measurement accuracy, data reliability, and electrical system compatibility, enhancing sensor's linearity has become increasingly critical. Analysis shows that the nonlinearity of flexible sensors primarily originates from mechanical nonlinearity due to the nolinear deformation of polymers and electrical nonlinearity caused by changes in parameters such as resistance. These nonlinearities can be mitigated through geometric design, material design or combination of both. This work reviews linear design strategies for sensors from the perspectives of structure and materials, covering the following main points: (a) an overview of the fundamental working mechanisms for various sensors; (b) a comprehensive explanation of different linear design strategies and the underlying reasons; (c) a detailed review of existing work employing these strategies and the achieved effects. Additionally, this work delves into diverse applications of linear flexible pressure sensors, spanning robotics, safety, electronic skin, and health monitoring. Finally, existing constraints and future research prospects are outlined to pave the way for the further development of high-performance flexible pressure sensors.

High-energy-density Li metal batteries with high charge voltage and fast charge/discharge rates are of great significance to the energy storage market. However, traditional carbonate-based electrolytes suffer from severe performance decay due to their oxidation and decomposition under high working voltages, and they are unable to prevent Li dendrite growth. Herein, we report an advanced concentrated ternary salt ether-based electrolyte which is compatible with a high charge voltage and exhibits a high rate capability in a Li metal-based Li|| LiNi0.6Mn0.2Co0.2O2 (NMC622) battery. Advanced electron microscopy reveals a stable Al-rich interphase in situ coated on the cathode surface due to the design of the electrolyte. This interphase suppresses the surface side effect and thus improves cell cyclability. Benefiting from the in situ coated interphase, the cell exhibits good capacity retention of similar to 85% after 300 cycles with a charge voltage of 4.4 V (C/3 charge and 1 C discharge). This work offers a promising strategy for developing practical secondary batteries based on Li metal with outstanding high voltage and rate performance.

Abstract A new concentrated ternary salt ether‐based electrolyte enables stable cycling of lithium metal battery (LMB) cells with high‐mass‐loading (13.8 mg cm−2, 2.5 mAh cm−2) NMC622 (LiNi0.6Co0.2Mn0.2O2) cathodes and 50 μm Li anodes. Termed “CETHER‐3,” this electrolyte is based on LiTFSI, LiDFOB, and LiBF4 with 5 vol% fluorinated ethylene carbonate in 1,2‐dimethoxyethane. Commercial carbonate and state‐of‐the‐art binary salt ether electrolytes were also tested as baselines. With CETHER‐3, the electrochemical performance of the full‐cell battery is among the most favorably reported in terms of high‐voltage cycling stability. For example, LiNixMnyCo1–x–yO2 (NMC)‐Li metal cells retain 80% capacity at 430 cycles with a 4.4 V cut‐off and 83% capacity at 100 cycles with a 4.5 V cut‐off (charge at C/5, discharge at C/2). According to simulation by density functional theory and molecular dynamics, this favorable performance is an outcome of enhanced coordination between Li+ and the solvent/salt molecules. Combining advanced microscopy (high‐resolution transmission electron microscopy, scanning electron microscopy) and surface science (X‐ray photoelectron spectroscopy, time‐of‐fight secondary ion mass spectroscopy, Fourier‐transform infrared spectroscopy, Raman spectroscopy), it is demonstrated that a thinner and more stable cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) are formed. The CEI is rich in lithium sulfide (Li2SO3), while the SEI is rich in Li3N and LiF. During cycling, the CEI/SEI suppresses both the deleterious transformation of the cathode R‐3m layered near‐surface structure into disordered rock salt and the growth of lithium metal dendrites.

The high reactivity of Li metal and the security issues of electrolytes impede the practicality of lithium-metal batteries (LMBs). Herein, we propose a new localized high-concentration electrolyte (LHCE) in which, for the first time, 2,2,3,3-tetrafluoropropyl difluoromethyl ether (TDE) is employed as diluent in ether-based LHCE enables flame-retarded, broad electrochemical stability window, dendrite-free Li depositing, high Li anode cycling Coulombic efficiency (CE, 99.2%), and significantly improves cycling performance of Li||NMC811 bat-teries. It enables Li||NMC811 with limited 50 & mu;m thickness Li metal anode and high loading capacity NMC811 cathode (14.8 mg cm- 2, 2.96 mAh cm- 2) to achieve a stable cycle with an ultrahigh cut-off voltage of 4.6 V. Molecular Dynamics (MD) simulation further corroborates the addition of hydrofluoroether diluents caused countersolvent effect to reinforce the association between Li+ cations and FSI- anions. However, an excessive amount of -CF2- in the diluent backbone would decrease the solubility of Li-salt in solvent, which is detrimental to the stability of electrolyte.

在前期"专创融合"课程体系构建的基础上,进行了体系的实践,取得了一定的成效.该文论述了"专创融合"课程体系实践现状和成效,构建了具有材料成型及控制工程专业特色的"专创融合"模式.从因地制宜、理实结合和完善制度三个方面具体实施了"专创融合"课程体系,提高了学生学习专业课程的兴趣,也培养了学生的创新创业能力,取得了良好的教学效果.

The spheroidization of cathode is extremely important for improving tap density and cycle stability. However, the spherical cobalt-free Li-rich and Mn-based cathode of xLi(2)MnO(3)center dot(1-x)LiMO2 (M = Fe, Ni, Mn, LFNMO) have not been successfully synthesized so far. For the first time, a spherical cobalt-free 0.6Li(2)MnO(3)center dot 0.4Li [Fe1/3Ni1/3Mn1/3]O-2 cathode is synthesized via co-precipitation approach in this work. It exhibits small Brunauer-Emmett-Teller (BET) specific surface area (2.56 m(2) g(-1)) and high tap density (2.11 g cm(-3)). Meanwhile, an excellent cycle stability is also achieved, which delivers a high reversible capacity of 208 mAh g(-1) at C/10 after 100 cycles. Further investigation demonstrates that the optimized sodium carbonate (Na2CO3) precipitant and suitable pH could adjust the solubility product (K-sp) of the precipitate and make the Fe2+, Ni2+ and Mn2+ precipitate simultaneously according to the designed stoichiometric ratio to form the spherical precursor, which is the key to forming the spherical LFNMO. The spherical LFNMO could reduce the side reactions between cathode and electrolyte, form thin cathode electrolyte interphase (CEI) and suppress the electrolyte corrosion to cathode, hence improving electrochemical performance. This work expatiates the synthesis condition and mechanism to prepare spherical LFNMO via co-precipitation, which might greatly advance the designing and development of cathode materials.

Lithium metal batteries have been considered as one of the most promising high-energy-density energy storage devices, however, the low Coulombic efficiency and uncontrolled dendrite growth seriously hinder their commercialization. In lithium metal batteries, the electrolytes would directly participate in the formation of solid electrolyte interface (SEI), which play important roles in affecting the lithium metal anode Coulombic efficiency and inhibiting the growth of lithium dendrites.In the traditional LiPF6 based ester electrolyte, lithium metal anode exhibits low Coulomb efficiency and serious lithium dendrites.In recent years, significant improvement has been achieved for the protection of lithium anode through manipulating the electrolyte additive, solvents, lithium salt and lithium salt concentration,etc. For examples,ether solvent presenting better compatibility with lithium metal was selected to reduce the side reactivity of electrolyte with lithium metal;varieties of additives were adopted to suppress the formation of lithium dendrites;high concentration electrolytes were employed to form stable SEI.In this paper, the growth principles of lithium dendrites, the research status of electrolytes chemistries for protection of lithium metal anode by means of solvents, lithium salts, additives and high concentration electrolytes strategies were reviewed and the advantages and limitations of various approaches were summarized.New insights on the development of electrolytes chemistries were also put forward to stimulate new strategies to face the subsequent challenges of lithium-metal batteries.

The silicon-based material exhibits a high theoretical specific capacity and is one of the best anode for the next generation of advanced lithium-ion batteries (LIBs). However, it is difficult for the silicon-based anode to form a stable solid-state interphase (SEI) during Li alloy/de-alloy process due to the large volume change (up to 300%) between silicon and Li4.4Si, which seriously limits the cycle life of the LIBs. Herein, we use strontium fluoride (SrF2) particle to coat the silicon-carbon (Si/C) electrode (SrF2@Si/C) to help forming a stable and high mechanical strength SEI by spontaneously embedding the SrF2 particle into SEI. Meanwhile the formed SEI can inhibit the volume expansion of the silicon-carbon anode during the cycle. The electrochemical test results show that the cycle performance and the ionic conductivity of the SrF2@Si/C anode has been significantly improved. The X-ray photoelectron spectroscopy (XPS) analysis reveals that there are fewer electrolyte decomposition products formed on the surface of the SrF2@Si/C anode. This study provides a facile approach to overcome the problems of Si/C electrode during the electrochemical cycling, which will be beneficial to the industrial application of silicon-based anode materials.

文章首先阐述了卓越计划2.0的总体思路及重点任务,然后论述了基于卓越计划2.0的材料成型及控制工程专业教学实施基础,最后提出了基于卓越计划2.0的材料成型及控制工程专业教学改革.

Although there have been many studies on atomic layer deposition of Al2O3 to improve the electrochemical performances of ternary cathode materials, few studies considered the harsh conditions such as high temperature and high voltage at the same time. In this work, the Al2O3 passivation layer is employed to coat the high nickel (Ni) LiNi0.68Co0.10Mn0.22O2 cathode through atomic layer deposition (ALD) approach. The Al2O3 coated LiNi0.68Co0.10Mn0.22O2 presents superior cycling stability and rate capability than the pristine at the cut-off voltage of 2.7-4.4 V under room temperature. Furthermore, under the harsh condition at high temperature of 60 degrees C or at high voltage of 2.7-4.8 V, the Al2O3 coated LiNi0.68Co0.10Mn0.22O2 also shows significantly improved performances than the pristine. The superior electrochemical performance of Al2O3 coated LiNi0.68Co0.10Mn0.22O2 could be attributed to the enhanced interfacial stability, the mitigated side reactions with electrolyte and the better maintained lithium ion diffusion kinetics. Manipulating the surface coating chemistry and evaluating the performance under harsh condition provide a useful approach for fast screening of effective surface modification technology, which might significantly advance the development of high energy density cathode materials.

Due to higher theoretical specific capacity and lower electrochemical redox potential, lithium metal is considered an ideal anode material for high specific energy batteries. However, safety problems related to the uncontrolled growth of lithium dendrites and the volume expansion of lithium have hindered its commercialization. This paper reports a viscoelastic interface based on viscoelastic polymer (hydroxypropyl methyl cellulose) to protect lithium metal anode. The lithiophilic interface has good chemical, electrochemical and mechanical stability, which makes the dendrite-free and low volume expansion lithium possible. The Li/Li symmetrical battery based on anode protected by viscoelastic interface show better cycle stability and longer cycle life. The morphologies after cycles show a relatively smooth and dense lithium deposition. Li/LFP full battery test results show higher reversible capacity at higher C-rate, high capacity retention (85.2%) and stable coulomb efficiency (99.5%) at 0.2C after 200 cycles. This work provides insight into the strategy of interfacial engineering to protect lithium metal anode.

Slow lithium storage reaction kinetics and huge volume changes are the main limiting factors for the large-scale application of transition metal oxide anode materials for lithium ion batteries. Developing multi-structure and carbon coating films is a promising solution. Herein, a facile strategy for synthesizing novel binder-free 3D porous Fe3O4-Fe2P-Fe@C films is proposed based on the electrodeposition of self-supporting porous FeOOH-FeP-Fe films, glucose coating to form FeOOH-FeP-Fe@Glucose films, and oxygen-free annealing treatment for the decomposition of FeOOH into Fe3O4, phase separation of FeP into Fe2P-Fe3P and pyrolysis of glucose into C. The binder-free Fe3O4-Fe2P-Fe@C film anode exhibits high reversible capacity (914 mA h g(-1) after 200 cycles at 0.1 A g(-1)), superior rate capability (518 mA h g(-1) at 5 A g(-1)), and stable long cycling performance (723 mA h g(-1) after 500 cycles at 2 A g(-1)). The excellent lithium storage performance of the Fe3O4-Fe2P-Fe@C anode is attributed to the synergistic effects of the self-supporting 3D porous film structure, mull-phase structure, and carbon coating, which not only enhances the Li+ and electron transport to accelerate the reaction kinetics, but also buffers the volume changes to improve the structure stability during reversible charge-discharge process.

LMBs using an FEC optimized dual-salt electrolyte present excellent electrochemical performances because it could form a stable CEI and robust SEI.

文章首先分析了材料成型及控制工程专业生产实习的现状,然后提出了专业认证导向下的材料成型及控制工程专业生产实习改革的策略,包括以毕业要求为导向,合理设计生产实习方案;以学生为中心,完善生产实习环节;以解决材料成型中的复杂问题为出发点,不断探索新培养方向;以推陈出新为目标,不断探索最佳生产实习教学模式.

Medical Mg-based alloys are extensively applied because of its degradability, low elastic modulus, etc In this study, Mg-3Zn alloy was prepared by semi-solid powder moulding. Firstly, pure Mg powders with 3 wt% of pure Zn powders were mixed, and then the mixture were compressed into a designed mould at 540, 560, 580, 600, and 620 degrees C, respectively. The results show that as the temperature increases, relative density, the compressive strength and microhardness increase firstly and then decrease when the temperature reaches to 620 degrees C. The highest relative density, microhardness and compressive strength is 97.4%, 125 HV, 315.4 MPa, respectively at the forming temperature of 600 degrees C. The microstructure is mainly composed of alpha-Mg with a little of intermetallic phases (MgZn2, Mg4Zn7 and Mg51Zn20), the grain morphology is equiaxed grain with the size of about similar to 30 mu m. When prepared at a low temperature, the main combination mechanism of powders is hot rolling densification. Flowing and filling of liquid is the main combination mechanism at high temperature. Broken-up of particles and deformation including viscoplastic deformation contribute to the densification. More Mg was dissolved into Zn as the temperature increases, and the liquid fraction is mainly influenced by the dissolved Mg content. The sample prepared at 600 degrees C has a lowest corrosion rate (0.09 mm/year), which proves that semi-solid powder moulding is a promising method to prepare medical Mg-based alloys.

Medical Mg-based alloys are extensively applied because of its degradability, low elastic modulus, etc. In this study, Mg–3Zn alloy was prepared by semi-solid powder injection moulding, a novel method combining metal injection moulding and thixomoulding in one step. Firstly, pure Mg powders with 3 wt% of pure Zn powders (the mean diameter is 50 μm) were mixed, and then the mixture were injected at 540, 560, 580, 600, and 620 °C, respectively with the loading force of 5 t. The effect of injection temperature on the microstructure, and its corresponding mechanical properties were investigated. The densification process and combination mechanism were analyzed as well. The results show that as the temperature increases, relative density, the compressive strength and microhardness increase first and then decrease when the temperature reaches to 620 °C. The highest relative density, microhardness and compressive strength is 97.4%, 125 HV, 315.4 MPa, respectively at the injection temperature of 600 °C. The microstructure is mainly composed of α-Mg and intermetallic phases (MgZn2, Mg4Zn7 and Mg51Zn20), the grain morphology is equiaxed grains with size of about ~30 μm. When injected at low temperature, the main combination mechanism of powders is hot rolling densification. When injected at high temperature, flowing and filling of liquid is the main combination mechanism. Broken-up of particles and deformation including viscoplastic deformation contributes to the densification. More Mg was dissolved into Zn as the temperature increases, and the liquid fraction is mainly influenced by the dissolved Mg content.

Fe-Ni-Co-Ti形状记忆合金因其优越的性能,越来越多学者参与到其的研究当中.本文针对两种不同成分的Fe-Ni-Co-Ti形状记忆合金,在经过不同的热处理工艺后,采用金相观察、XRD试验和DSC试验的方法,对合金组织形貌变化和相变特性进行了研究.

A nanoscale tungsten nitride/nitrogen-doped carbon (WN/NC) catalyst was synthesized through a facile route, and it exhibited efficient catalytic performance for hydrogen and oxygen recombination at room temperature with an average catalytic velocity of 140 mol h(-1) g(cat)(-1) and long catalytic life of 954660 s without decay in the catalytic performance. With the WN/NC catalyst, a nickel-iron battery could be sealed and maintenance-free, and it also exhibited low cost; thus, the nickel-iron battery can be used for large-scale energy storage systems in rural/remote areas.

Copper/iron composite anode materials were synthesized by one-step co-precipitation method followed by calcination at high temperature in this paper, which had shown excellent high-rate discharge capacity and low temperature capability. Even the discharge-rate is as high as 10 C (1 C=200 mA g(-1)), or the temperature is as low as 253 K, the batteries still exhibited good discharge capacity (130 mA h g(-1) and 115 mA h g(-1), respectively). XRD and SEM results revealed that under the reduction treatment of acetylene carbon black at high temperature, copper atoms were preferentially reduced, removed from the spinel lattice and deposited on the surface, leading to the formation of porous structure with high specific surface. EIS and polarization tests proved that the copper/iron composite anode materials not only delayed the passivation but also raised the hydrogen evolution overpotential, both improved the dynamics of the iron electrode.