Nonaqueous potassium-ion full-cells:Mapping the progress and identifying missing puzzle pieces

This review addresses the growing interest for potassium-ion full-cells(KIFCs)in view of the transition from potassium-ion half-cells(KIHCs)toward commercial K-ion batteries(KIBs).It focuses on the key parameters of KIFCs such as the electrode/electrolyte interfaces challenge,major barriers,and recent advancements in KIFCs.The strategies for enhancing KIFC performance,including interfaces co ntrol,electrolyte optimization,electrodes capacity ratio,electrode material screening and electrode design,are discussed.The review highlights the need to evaluate KIBs in full-cell configurations as half-cell results are strongly impacted by the K metal reactivity.It also emphasizes the importance of understanding solid electrolyte interphase(SEI)formation in KIFCs and explores promising nonaqueous as well as quasiand all-solid-state electrolytes options.This review thus paves the way for practical,cost-effective,and scalable KIBs as energy storage systems by offering insights and guidance for future research.

Cu-0.23%Al_2O_3弥散强化铜合金的高温变形特性研究

利用Gleeble-1500热模拟机、金相以及透射电镜对Cu-0.23%Al_2O_3(体积分数)合金高温塑性变形过程中的流变应力和显微组织变化规律进行了研究.研究结果表明,Cu-0.23%Al_2O_3合金在热压缩过程中,热压缩条件不同流变应力变化规律会有所差异.此外,还求得了该合金高温变形的平均激活能和其他相关材料常数,据此建立了峰值屈服应力-应变速率-温度之间的本构方程.随热压缩温度的升高,基体内动态再结晶晶粒尺寸和数量不断增加,而在同一温度压缩时,随应变速率的增加,组织分布不均匀性有所增加,亚晶尺寸不断减小,位错密度先增加后降低.

Contribution to thermochemical studies of 0.8[xB_2O_3-(1-x)SiO_2]-0.2Na_2O glasses

Calorimetric measurements in 0.8[xB2O3-（1 - x）SiO2]-0.2Na2O glasses and melts are performed in I-IF calorimetry at 298 K and lead borate calorimetry at 973 K, respectively. Mixing enthalpy is affected by both temperature and composition. At 298 K, the mixing enthalpies are slightly negative and components are miscible at that temperature in the whole composition range. At 973 K, the sign of the mixing enthalpies reflect the tendency to phase separation at silica-rich compositions, which is avoided for kinetic reasons as shown by SEM results. Therefore, one is tempted to consider the quenched 0.8[xB2O3-（1 - x）SiO2-0.20Na2O] glasses and melts as single-phase materials.

Influence of alkali mixed effect on the mixing enthalpy in 0.75B_2O_3-0.25[xNa_2O-(1-x)K_2O]glass system

The mixed alkali effect was investigated in the glass system 0.75B2O3-0.25[xNa2O-（1 -x）K20] through thermodynamic properties. The calorimetric measurements were performed in HF solution calorimetry at 298 K. The mixing enthalpy values show non-linear behaviour upon substitution of one alkali ion by another. This thermodynamic non-ideality is caused by the slight variations of distance between metallic cations, the macromolecular structure being unchanged. It can be explained, at least qualitatively, using electrolyte theory based on the Coulombic interactions of charged species originally developed by Debye and Hückel.

Natural Rubber-Based Ionogels

Natural rubber(NR),besides being an abundant renewable resource for the elastomer industry,can be a potential resource for the design of innovative biobased polymer networks.The present work is based on“telechelic”liquid natural rubber oligomers obtained by controlled chemical degradation of NR.The chain ends of such oligomers can then be functionalized(with acrylate functions in the present case)and reacted with multifunctional crosslinkers in order to form networks.What’s more,the initial solubility of such thermosetting system in an ionic liquid(IL)can be used for the formulation of ionogels.Such solid networks typically containing 80%of IL were produced,resulting in high ionic conductivity performances.The oligomer chain length was shown to affect IL fragility due to confinement and specific interactions of ions with the host polymer network.

Understanding the Assembly Mechanism of Proteins from Monte Carlo Simulations

Understanding the molecular mechanism of the protein assembly still remains a challenge in the case of many biological systems. In this frame, the mechanism which drives RodA hydrophobins to self-assemble onto the surface of the conidia of the human fungal pathogen Aspergillus fumigatus into highly ordered nanorods known as rodlets, is still unresolved. Here, AFM investigations were combined with Monte Carlo simulations to elucidate how these small amphiphilic proteins self-assemble into tightly packed rodlets and how they are further organized in nanodomains. It becomes that the assembly of RodA hydrophobins into rodlets and their parallel alignment within nanodomains result from their anisotropic properties. Monte Carlo simulations allowed us to confirm that anisotropic interactions between macromolecules are sufficient to drive them to assembly into rodlets prior to nanodomains formation. Better knowledge of the mechanism of hydrophobins assembly into rodlets offers new prospects for the development of novel strategies leading to inhibition of rodlet formation, which should allow more rapid detection of the conidia by the immune system.

Effect of CuI Anode Buffer Layer on the Growth of Polymers Thin Films and on the Performances of Organic Solar Cells

Organic photovoltaic cells using polymer belonging to the aniline-heteroaryl family as electron donor have been achieved by thermal evaporation. We show that the properties of the polymer film, morphology, molecule order and conductivity depend strongly on the bottom anode buffer layer. While cells without anode buffer layer or with MoO3 or CuI anode buffer layer have been probed, we show that CuI allows improving strongly the cells efficiency through an improvement of the morphology and conductivity of the polymer film. This shows that although it is necessary a good band matching at the interface, this is not sufficient, because the templating effect of CuI on the polymer film is primordial for photovoltaic cells improvement.

Fabrication Parameter Optimization for a Multilayer Photovoltaic Cell Based on the Heterojunction: Zinc(II)-Meso-Tetrakis(4-Bromophenyl) Porphyrins/Fullerenes

The photoelectric properties of multilayer organic photovoltaic cells (OPV cells) were studied. The active organic layers consisted of a planar heterojunction between a layer of Meso-Tetrakis(4-BromoPhenyl) Zinc(II) Porphyrin (BrPhPZn) as electron donor (ED) and a layer fullerene molecules. The devices were fabricated in a high vacuum by thermal sublimation, a technique that allows multilayer devices realization easily by successive depositions, and it does not require solvents, achieving purer films with reproducible characteristics. Taking into account that the anodic contact, a key factor for cell efficiency, is favored by the inclusion of a thin anodic buffer layer (ABL), the effect on the yield after including one or two (ABL): MoO3 or MoO3-CuI layers was studied. The cell which has the best photovoltaic characteristics has a BrPhPZn (ED) thickness of only 12.5 nm. This small thickness is related with the low conductivity of this organic molecule. On the other hand, including a thin MoO3-CuI bilayer increased, such device’s efficiency in a 200%, with regard to a cell without ABL, getting for one cell ITO/MoO3-CuI/BrPhPZn/C60/Alq3/Al, with a 1.03% yield.

Polypeptide Brushes Grown via Surface-initiated Ring-opening Polymerization of α-Amino Acid N-Carboxyanhydrides

Polypeptide brushes are attractive platforms to generate functional and responsive interfaces that are of potential interest due to their possible biodegradability, biocompatibility and tunable secondary structures. Surface-initiated ringopening polymerization（SI-ROP） of α-amino acid N-carboxyanhydrides represents a powerful and versatile strategy to generate polypeptide brushes. This review is an attempt to capture the state-of-the-art in this field and highlights the latest developments in several selected areas. In addition to presenting an overview of the synthetic methods that have been used to generate polypeptide brushes via SI-ROP, this article will discuss the preparation of patterned polypeptide brushes, the conformational properties of surface-tethered polypeptides, ways to control chain orientation at surfaces as well as properties and applications of these thin polymer films.

Vapor dealloying of ultra-thin films: a promising concept for the fabrication of highly flexible transparent conductive metal nanomesh electrodes

The booming market of flexible electronic displays has urged the development of highly flexible transparent conductive electrodes(FTCE)1–3 with the ability to replace indium tin oxide(ITO)thin films routinely used as transparent conductive electrodes in photoelectronic devices.The high cost of indium and the poor mechanical stability of ITO under deformation are the main driving forces behind the development of this research area.4 The use of metal nanomeshes as FTCE is a promising concept with a real potential to substitute ITO in photoelectronic devices.5,6 However,the development of a low-cost fabrication approach allowing producing metal nanomesh electrodes with competitive prices and a high performance remains a real bottleneck for the photoelectronic industry.In this paper,we report on a robust approach very easy to implement allowing producing highly flexible metal nanomesh electrodes with high performance at a very low cost.This approach lies on a concept consisting in applying dealloying process to ultra-thin Au-Cu alloy thin films using acidic vapors instead of a liquid phase as routinely done in the literature.Using an appropriate procedure,the nanomeshes can be transferred to any planar or curved support where they can serve as a FTCE.As a proof of concept,we demonstrate that using this approach,one can easily fabricate gold nanomesh electrodes transferred onto polyethylene terephthalate(PET)film surface with 79%of transmittance and a sheet resistance as low as 44Ω□^(−1) while maintaining exceptional stability under severe mechanical deformations.

Toward Rational Composite Electrodes for Improved Li Batteries

1 Results Although electrodes for lithium batteries are generally prepared with standard formulations and routine processing conditions,more and more studies report relationships between processing conditions,composite electrode morphology and electrochemical performance.In our previous work,we obtained a 50% increase of the cycling capacity of Li1.1V3O8 based electrodes after using a PEO binder which had been pre-plasticized by the solvent (ethylene carbonate (EC) + propylene carbonate (PC)) of the liq...

Origin of Capacity Fading for Nano-grains Based Electrodes of Li Rechargeable Batteries

1 Results Li1+xV3O8,has been extensively investigated as a positive electrode material for lithium metal polymer batteries and a great deal of interest has been focused on the structural characterization and cyclability of this compound[1-6].From the present work,Li1.1V3O8 nanograins synthesized at low temperature from original two component gel precursor suffer from strong capacity fading on cycling.The latter is characterized by emergence of polarized redox processes at the expense of initial ones.Fro...

Magnesium borohydride Mg(BH_(4))_(2) for energy applications:A review

Mg(BH_(4))_(2) with several polymorphs,known as a high capacity(14.9 wt.%)hydrogen storage material,has become more intriguing due to the recently found new functions of gas physisorption and ionic conduc-tivity.Here we review the state-of-the-art on the energy related functions of Mg(BH_(4))_(2).Mg(BH_(4))_(2) tends to form the stable intermediate[B_(12)H_(12)]^(2−) when the dehydrogenation temperature is above 400℃,the strong B-B bonding of which makes the rehydrogenation condition very harsh.In contrast,lower borane intermediate[B_(3)H_(8)]2−facilitates the rehydrogenation even at a mild condition of 100℃,suggesting the possibility of reversible hydrogen storage in Mg(BH_(4))_(2).The porous polymorphγ-Mg(BH_(4))_(2) shows attrac-tive gas adsorption properties in view of its unique hydridic surface and pore shape,and potentially can be applied in hydrogen adsorption and Kr/Xe selectivity.A new diffraction-based adsorption methodology was developed to characterize adsorption thermodynamics and kinetics ofγ-Mg(BH_(4))_(2),providing a novel idea for the characterization of crystalline porous materials.Moreover,the potential of Mg(BH_(4))_(2) as an electrolyte is discussed in the last part.Mg(BH_(4))_(2)·THF/DME acts as a liquid electrolyte in Mg-batteries,while anion substituted or neutral molecule derivatives of Mg(BH_(4))_(2) can act as solid-state electrolyte.

All-in-One Deposition to Synergistically Manipulate Perovskite Growth for High-Performance Solar Cell

Nonradiative recombination losses originating from crystallographic distortions and issues occurring upon interface formation are detrimental for the photovoltaic performance of perovskite solar cells.Herein,we incorporated a series of carbamide molecules(urea,biuret,or triuret)consisting of both Lewis base(-NH2)and Lewis acid(-C=O)groups into the perovskite precursor to simultaneously eliminate the bulk and interface defects.Depending on the different coordination ability with perovskite component,the incorporated molecules can either modify crystallization dynamics allowing for large crystal growth at low temperature(60℃),associate with antisite or undercoordinated ions for defect passivation,or accumulate at the surface as an energy cascade layer to enhance charge transfer,respectively.Synergistic benefits of the above functions can be obtained by rationally optimizing additive combinations in an all-in-one deposition method.As a result,a champion efficiency of 21.6%with prolonged operational stability was achieved in an inverted MAPbI3 perovskite solar cell by combining biuret and triuret additives.The simplified all-in-one fabrication procedure,adaptable to different types of perovskites in terms of pure MAPbI3,mixed perovskite,and all-inorganic perovskite,provides a cost-efficient and reproducible way to obtain high-performance inverted perovskite solar cells.

Nanosize Effects on Structural and Electrlcal Properties of Conjugated Polymer Nanowires

1 Introduction Conjugated polymer nanofibers (nanowires,nanotubes,nanorods) are promising as building-blocks for many applications,such as bio- and chemical sensors and drug release,field emission or electrochromic displays,nanodevices,and nano OLEDs.Understanding the mechanisms responsible for their unique electrical,optical and electrochemical properties is thus a foremost point.Here,we report for the first time on a systematic study with the diameter of the electrical properties in Poly(3,4-ethylened...