Inhibition Of Dendritic Growth Research Articles

Anti-dissolving cellulose-based separator for dendrite-free rechargeable aluminum batteries

Rechargeable aluminum batteries (RABs) are noteworthy due to their environmental sustainability and cost-effectiveness. However, its practical applications suffer from wilder growth of anode dendrites and greater physicochemical instability of separator triggered by corrosive ionic liquid electrolytes (ILs). This work produces a core-shell structured CCP@TiO2 separator by introducing TiO2 nanolayer onto commercial cellulose paper (CCP) to improve its stability by tackling the challenge of cellulose dissolution in ILs. By combining experimental and simulation studies, CCP@TiO2 separator exhibits excellent anti-dissolving property and interfacial polarization effect, not only provides the stable anion flux and high anion transfer number of 0.29, but also facilitates the uniform distribution of the ions and electric charges at the separator/electrolyte/anode interface, thereby promoting dendrite-free Al deposition. Thus, the assembled graphite//Al battery maintains a higher discharge capacity of 90.3 mAh g−1 after 1000 cycles at 0.2 A g−1, compared to the 82.4 mAh g−1 residual of that with glass fiber (GF) separator. Furthermore, the battery with secondary use CCP@TiO2 separator still maintains 98 % capacity retention. Such separator engineering of insolubility of cellulose in ILs and inhibition of dendrite growth, provides an unparalleled pathway for promising alternative to GF separator and stable operation, sustainable development of RABs.

Inhibition of dendrite growth and side reactions using histidine as electrolyte additive for aqueous Zn-ion batteries

Aqueous Zn-ion batteries have attracted wide attention in the field of energy storage due to their low cost and high safety. However, the problems of dendrite growth and side reactions of Zn anode have been puzzling them and become the main factors limiting their development and application. Herein, we introduce histidine additive into the ZnSO4 electrolyte to inhibit dendrite growth and side reactions. The histidine is preferentially adsorbed on the surface of Zn anode to form a shield molecular layer, guiding the uniform deposition of Zn ions and inhibiting the side reactions. Consequently, an long cycle life of 4180 h for Zn||Zn symmetric battery can be achieved at 2 mA cm–2 (1 mAh cm–2), and even at the ultra-high current density of 10 mA cm–2 (5 mAh cm–2) for more than 1000 h. The capacity retention of Zn-MnO2 full battery with His/ZnSO4 retains 64% after 800 cycles of charge/discharge at 0.5 A g–1, while 47% for the full battery with pure ZnSO4 electrolyte. This work provides an effective electrolyte additive to address the dendrite growth and side reactions in Zn-ion batteries.

Effects of Various Valence Ions on Aqueous RechargeableZn//Polyaniline-coated ZnMn2O4 Battery.

Zinc corrosion and dendrite formation are the main issues which impede the performance of aqueous zinc ion batteries (ZIBs) after certain times. In this work, we systematically investigated the effects of three different valence ions (e.g., Na+, Mg2+, Al3+) as electrolyte additives on the suppression of zinc corrosion and the inhibition of dendrite growth. By combining experiments and theoretical calculations, it has been found that the existence of Na+ ions effectively suppressing the zinc dendrite growth because Na+ possessess high adsorption energy approximately -0.39 eV. Moreover, Na+ ions could lengthen the zinc dendrite formation duration up to 500 hours. On the other hand,, the PANI/ZMO cathode materials showed the small band gap approximately 0.097 eV, signifying that the PANI/ZMO possessed the semiconductor characteristics. Furthermore, an assembled Zn//PANI/ZMO/GNP full battery using Na+ ions as electrolyte additive displayed capacity retention of 90.2 % after 500 cycles at 0.2 A g-1, whereas the capacity retention of the control battery using pure ZnSO4 electrolyte was only 58.2 %. This work could provide a reference for the selection of electrolyte additives in future batteries.

Redistributing zinc-ion flux by constructing a hybrid conductor interface for dendrite-free zinc anode

Rechargeable aqueous zinc-metal batteries have attracted soaring attention as alternative to conventional lithium-ion batteries for energy storage systems due to the high safety, low cost, and environmental benignancy. However, the spontaneous side reaction and dendrite growth lead to the poor electrochemical performance as well as serious safety issues. Herein, a multifunctional layer composed of zinc alginate (ZA) and vermiculite sheets (VS) is coating on zinc foil surface to simultaneously suppress the side reaction and dendrite growth. Unique Zn2+ channels built by ZA polymer and VS endow the ZAVS film with high zinc-ion transference number (tZn2+ = 0.81), which can both improve the migration of Zn2+ and redistribute the Zn2+ flux on the electrode surface. Consequently, dendrite growth is obviously inhibited. In addition, ZAVS film can serves as a buffer layer to isolate zinc anode from aqueous electrolyte, alleviating the zinc corrosion and hydrogen generation. Benefiting from the inhibition of dendrite growth and side reaction, superior electrochemical performance can be achieved as evidenced by the high Coulombic efficiency of 99.18% for 520 cycles, and ultra-long cycling stability over 1000 h with small voltage hysteresis. The construction of ZAVS artificial layer could be a promising strategy for advanced RAZMBs.

Phase-Field Simulation and Machine Learning Study of the Effects of Elastic and Plastic Properties of Electrodes and Solid Polymer Electrolytes on the Suppression of Li Dendrite Growth.

Lithium (Li) dendrite growth in Li batteries is a long-standing problem, which causes critical safety concerns and severely limits the advancement of rechargeable Li batteries. Replacing a conventional liquid electrolyte with a solid electrolyte of high mechanical strength and rigidity has become a potential approach to inhibiting the Li dendrite growth. However, there still lacks an accurate understanding of the role of the mechanical properties of the metal electrode and the solid electrolyte in the Li dendrite growth. In this work, we develop a phase-field model coupled with the elastoplastic deformation to investigate the Li dendrite growth and its inhibition in the cell. Different mechanical properties, including the elastic modulus and the initial yield strength of both the metal electrode and the solid electrolyte, are explored to understand their independent roles in the inhibition of Li dendrite growth. High-throughput phase-field simulations are performed to establish a database of relationships between the aforementioned mechanical properties and the Li dendrite morphology, based on which a compressed-sensing machine learning model is trained to derive interpretable analytical correlations between the key material parameters and the dendrite morphology, as described by the dendrite length and area ratio. It is revealed that the Li dendrite can be effectively inhibited by electrolytes of high elastic moduli and initial yield strengths. Meanwhile, the role of the yield strength of the Li metal is also critical when the yield strength of the electrolyte becomes low. This work provides a fundamental understanding of the dendrite inhibition by mechanical suppression and demonstrates a computational data-driven methodology to potentially guide the electrode and electrolyte material selection for better inhibition of the dendrite growth.

Applications of two-dimensional material-functional separator in lithium battery

In recent years, people’s continuous attention to energy crisis and environmental problems has promoted the development of electric energy storage technology. The emergence of lithium-ion battery (LIB) has profoundly impacted on society by providing energy storage for portable electronic devices, medical devices and electric vehicles. However, the electrode materials can only contribute a low capacity due to the intercalation reaction chemistry, specific capacity of Li-ion batteries cannot be further improved. Therefore, lithium secondary battery systems with higher energy and power density need to be developed for the next generation of electric vehicles.The lithium metal has an extremely high theoretical specific capacity (3860 mAh/g) and low redox potential (–3.04 V vs. standard hydrogen electrode), giving the lithium battery a high energy density when used as a anode material. And when sulfur used as a cathode material, its theoretical specific capacity reaches 1672 mAh/g, thus the theoretical energy density of the lithium sulfur (Li-S) battery system is as high as 2600 Wh/kg. However, the polysulfides in Li-S battery seriously affect the safety and electrochemical performance of the cell. When lithium metal used as anode materials, the uncontrolled dendrite growth also brings serious safety risks to users. Therefore, all the basic components of lithium batteries, including the anode, cathode, separator and electrolyte, need to be optimized. Most of the current research has focused on the development of high-capacity anode and cathode materials. In fact, functional separators have an important impact on the safety and electrochemical performance of lithium secondary batteries. Compared with other materials that modified commercial polyolefin membranes, two-dimensional materials offer the advantages of ultra-thin laminate structure, high mechanical strength, high specific area, and adjustable surface chemical properties. Therefore, in Li-S batteries, two-dimensional material-functionalized separators can inhibit the shuttle effect of polysulfides through chemical adsorption and confined pore channels. In Li-metal batteries, the inhibition of dendritic growth by two-dimensional functional membranes is mainly due to its high mechanical strength, thermal conductivity and the ability to regulate ion transport flux through defect sites. And in Li-ion batteries, the two-dimensional functional separator mainly improves the wettability and poor thermal stability of routine polyolefin membrane, thus it greatly enhances the electrochemical performance and safety performance of lithium cells. This review first introduces the unique advantages of two-dimensional materials in the membrane, including parallel self-assembly feature, excellent mechanical strength and flexibility, ultrahigh specific surface area, surfaces are easily modified and element doped and ultrathin laminar structure. Then the review briefly describes the method of constructing two-dimensional materials separators and its characterization. Subsequently, this paper focuses on the application of different types of two-dimensional materials functional membranes in solving polysulfide shuttle effect in Li-S batteries, dendrite growth of anode in Li-metal batteries, as well as poor wettability and thermal stability of commercial separator in Li-ion batteries. Finally, the remaining opportunities and challenges of two-dimensional materials in Li battery separator materials are briefly discussed.

Dendrite-tolerant all-solid-state sodium batteries and an important mechanism of metal self-diffusion

Inhibition of dendrite growth in all-solid-state lithium batteries (ASSLBs) has long been a challenge to the field. In the present study, the conditions for dendrite growth for a similar but less mature technology, all-solid-state sodium batteries (ASSNBs), are investigated. By simply sticking sodium metal to Na3.4Zr2(SiO4)2.4(PO4)0.6 (NZSP) ceramic pellets and without applying external pressure during operation, the critical current density of Na/NZSP/Na symmetric ASSNBs reaches 9 mA cm−2 at 25 °C. The cells can be stably operated at an areal capacity of 5 mAh cm−2 (per half cycle, with 1.0 mA cm−2) at 25 °C for 300 h in a galvanostatic cycling measurement without any dendrite formation. The results outperform the existing ASSLBs and ASSNBs, and also go beyond satisfying the requirements for practical applications. The influence of the high metal self-diffusion coefficient on the dendritic plating/stripping is regarded as the most likely reason for the high dendrite tolerance of ASSNBs. A mathematical model based on Fick's second law was applied as a first approximation to illustrate this influence. Full ASSNBs were fabricated with infiltrated Na3V2(PO4)3 (NVP) as the cathode and can be stably operated with a capacity of 0.60 mAh cm−2 at high rate of 0.5 mA cm−2 at room temperature.

Simultaneously Enhanced Strength, Toughness and Ductility of Cast 40Cr Steels Strengthened by Trace Biphase TiCx-TiB2 Nanoparticles

Simultaneously improving the strength, toughness, and ductility of cast steels has always been a difficult problem for researchers. Biphase TiCx-TiB2 nanoparticle-reinforced cast steels are prepared by adding in situ nanosized biphase TiCx-TiB2/Al master alloy during the casting process. The experimental results show that a series of significant changes take place in the microstructure of the steel: the ferrite-pearlite structure of the as-cast steels and the bainite structure of the steels after heat treatment are refined, the grain size is reduced, and the content of nanoparticles is increased. Promotion of nucleation and inhibition of dendrite growth by biphase TiCx-TiB2 nanoparticles leads to a refinement of the microstructure. The fine microstructure with evenly dispersed nanoparticles offers better properties [yield strength (1246 MPa), tensile strength (1469 MPa), fracture strain (9.4%), impact toughness (20.3 J/cm2) and hardness (41 HRC)] for the steel with 0.018 wt.% biphase TiCx-TiB2 nanoparticles, which are increased by 15.4%, 31.2%, 4.4%, 11.5%, and 7.9% compared with the 40Cr steels. The higher content of nanoparticles provides higher strengths and hardness of the steel but are detrimental to ductility. The improved properties may be attributed to fine grain strengthening and the pinning effect of nanosized carbide on dislocations and grain boundaries. Through this work, it is known that the method of adding trace (0.018 wt.%) biphase TiCx-TiB2 nanoparticles during casting process can simultaneously improve the strength, toughness, as well as ductility of the cast steel.

Promote One, Inhibit the Other: A Single Pathway Controls Axon and Dendrite Growth, Oppositely

To make a functioning neuron, you need both a dendrite to receive signals and an axon to send them. Therefore a shared pathway, which stimulates the growth of both, might come in handy. But growing one or the other alone could also be beneficial, and so it would make sense to have dedicated pathways that could stimulate either process independently. Indeed, such shared and dedicated neuronal growth pathways have both been identified. But then there are times when it might be helpful to promote growth of one while inhibiting the other. In a new study in PLOS Biology, Xin Wang, Bing Ye, and colleagues demonstrate the existence of this kind of bimodal control in flies, and identify the molecular pathway that makes it possible. The authors focused on a signaling pathway known to control axon terminal growth. In flies, two key members of the pathway are Highwire and Wallenda. These two interact, in that Highwire suppresses expression of Wallenda, and loss of Highwire causes axonal overgrowth that can be reversed by loss of Wallenda. When the authors inactivated Highwire in a set of larval body wall neurons, not only did they observe the expected axon terminal overgrowth, but they also saw dramatic reduction of dendritic growth, leading to dendrites that were both shorter and less highly branched than normal. The neurons were otherwise normal, displaying expected molecular markers and finding their way to their appropriate targets on the fly nerve cord. Inactivating the gene for Wallenda reversed the axonal outgrowth, as expected, and also the inhibition of dendrite growth. Conversely, excess of Wallenda favored axon terminal growth and inhibited dendrite growth, strongly suggesting that Highwire and Wallenda work within a single pathway to regulate the growth of both axon and dendrite, with Highwire promoting dendrites and Wallenda axons. At some point, however, the pathway must split, in order to produce its divergent effects. Other experiments have shown that the Fos protein is a downstream effector of Wallenda. Here, inactivation of fos prevented axon terminal overgrowth when Wallenda was overexpressed, indicating it plays a key role in the axonal branch of the pathway. But Fos had no effect on dendritic growth, so the authors speculated that perhaps that branch involved one or more transcription factors with roles in growth of dendrites. They found that levels of one, called Knot, were reduced by either inactivation of Highwire or overexpression of Wallenda. Restoring Knot reversed the dendritic, but not the axonal, defects caused by Highwire inactivation. In sum, then, it appears that when Highwire suppresses expression of Wallenda, expression of Knot increases and leads to the elaboration of the dendritic tree. Conversely, when Wallenda expression is elevated, fos is activated and promotes axon terminal outgrowth, while Knot expression is reduced, inhibiting growth of dendrites. One possible benefit of this bimodal control system is to coordinate the response to axonal injury. Axon regrowth requires cellular resources of membrane and cytoskeletal proteins, which are abundant in the dendrite. It may be that the Highwire/Wallenda system maximizes the ability of the neuron to move resources to the axon by suppressing their use in the dendrite. In support of this possibility, shrinkage of dendrites is observed following experimental induction of axon damage. A better understanding of how neurons balance the competing needs of their two critical components should lead not only to a better understanding of normal neuronal growth and development, but also to better strategies for aiding neuronal repair after traumatic injury. Wang X, Kim JH, Bazzi M, Robinson S, Collins CA, et al. (2013) Bimodal Control of Dendritic and Axonal Growth by the Dual Leucine Zipper Kinase Pathway. doi:10.1371/journal.pbio.1001572 A functioning neuron (symbolized here as a tree) has both dendritic arbors to receive signals and axonal branches to send them.

Pituitary adenylate cyclase-activating polypeptide and vasoactive intestinal peptide inhibit dendritic growth in cultured sympathetic neurons.

Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are related neuropeptides that are released by the preganglionic sympathetic axons. These peptides have previously been implicated in the regulation of sympathetic neurotransmitter metabolism and cell survival in postganglionic sympathetic neurons. In this study we consider the possibility that PACAP and VIP also affect the morphological development of these neurons. Postganglionic rat sympathetic neurons formed extensive dendritic arbors after exposure to bone morphogenetic protein-7 (BMP-7) in vitro. PACAP and VIP reduced BMP-7-induced dendritic growth by approximately 70-90%, and this suppression was maintained for 3 weeks. However, neither PACAP nor VIP affected axonal growth or cell survival. The actions of PACAP and VIP appear to be mediated by PAC1 receptors because their effects were suppressed by an antagonist that binds to PAC1 and VPAC2 receptors (PACAP6-38), but not by an antagonist that binds to the VPAC1 and VPAC2 receptors. Moreover, exposure to PACAP and VIP caused phosphorylation and nuclear translocation of cAMP response element-binding protein, and agents that increase the intracellular concentration of cAMP mimicked the PACAP-induced inhibition of dendritic growth. These data suggest that peptides released by preganglionic nerves modulate dendritic growth in sympathetic neurons by a cAMP-dependent mechanism.