Preparation Of Anodes Research Articles

Zinc-tin binary alloy interphase for zinc metal batteries

Aqueous zinc ion batteries are rapidly developing as the most propitious energy storage system due to their high security, high specific capacity and low cost, etc. However, zinc anodes suffered from dendrite growth and hydrogen evolution reactions during cycling, so it is of utmost importance to upgrade zinc anode properties. In this study, the homogeneous layer of ZnSn alloy interphase was formed by introducing metallic tin to the anode surface using an ion sputtering technique. ZnSn alloy can reduce the hydrogen evolution over-potential of anode and the corrosion current, inhibiting the occurrence of hydrogen evolution and corrosion reaction. Moreover, the ZnSn alloy anode can provide uniform nucleation sites and uniformize the electric field on the anode surface, promote the uniform deposition of Zn2+, thus inhibiting the formation of zinc dendrites. Notably, compared to the Zn foil//Zn foil cell (400 h), the ZnSn alloy symmetric cell showed excellent cycling performance by cycling for 1000 h at 0.5 mA cm−2. Furthermore, even at current density of 1 A/g, the capacity retention of the ZnSn alloy//MnO2 full cell was up to 89.5 % compared to only 32.3 % for Zn foil//MnO2 cell. The preparation of this ZnSn alloy anode may provide new ideas for future alloying strategies.

Multifunctional zinc-nickel alloy enabling high-performance aqueous zinc ion batteries

Aqueous zinc ion batteries are considered to be the new type of secondary batteries that have the potential to replace lithium-ion batteries as the most widely used in the future due to their green environment, high specific capacity and abundant zinc resources. However, due to the contact between the zinc anode and electrolyte, the generation of by-products and corrosion phenomena are not completely avoided, which can easily lead to problems such as short cycle life and poor electrochemical performance of the battery. In this study, uniform zinc-nickel alloy (ZnNi) was prepared by melting method. The element nickel has excellent corrosion resistance and is widely used to improve the corrosion resistance of metal alloys, so the introduction of nickel effectively enhances the corrosion resistance of ZnNi alloys. In addition, metallic nickel shows strong attraction to Zn2+, which can promote the uniform distribution and deposition of Zn2+ and inhibit the dendrites growth to prolong the battery life. Notably, the ZnNi-assembled symmetric cell exhibited excellent cycling performance compared with the Zn//Zn cell (100 h), with a cycle life of up to 1000 h at 2 mA cm−2. In addition, the capacity retention rate of the ZnNi//MnO2 full cell was still as high as 90.6 % after 1000 cycles. The preparation of the ZnNi alloy anode may provide a new idea for future alloying strategies.

Biocompatible and capacitive PDA-Ov-Co3O4@CC anode augmented exoelectrogens enrichment and extracellular electron transfer in microbial fuel cells

Metal oxides rich in oxygen vacancies (Ov) possess excellent intrinsic conductivity, variable valence metal center and high capacitance, which were potential candidates as microbial fuel cells anode. However, their high bacterial toxicity greatly hindered the activity of biofilm. To solve this issue, in this work, polydopamine (PDA) covered capacitive Ov doped Co3O4 nanosheets were designed and successfully grown on carbon cloth (CC). The introduction of Ov significantly promoted the charge storage, the net charge and the accumulated charge were 217.1 and 2680.3 C/m2, respectively, surpassed Co3O4 anode without Ov. In addition, Ov also decreased the charge-transfer resistance (Rct), effectively accelerating EET. The Rct of PDA/Ov-Co3O4@CC was 29.51 Ω, lower than CC (382.10 Ω). The cover of PDA prevented the direct contact between metal ions and microorganisms, greatly enhanced the bacterial viability. The power density of MFCs with PDA/Ov-Co3O4@CC anode was 2.77 W/m2, 1.45 times higher than that of bare CC (1.90 W/m2). In addition, PDA/Ov-Co3O4@CC anode displayed excellent coulombic efficiency and daily COD removal amount (23.5 % and 147.6 mg/L/d), higher than the control groups. The community analysis showed the abundance of Geobacter on PDA/Ov-Co3O4@CC anode was 91 %, higher than other anodes. Present study developed a facile and effective PDA coating strategy to simultaneously enhance the biocompatibility and capacitance of Ov-rich metal oxides, which will be a promising method for the preparation of high performance MFCs anode.

Three-Dimensional Carbon Nanotubes Buffering Interfacial Stress of the Silicon/Carbon Anodes for Long-Cycle Lithium Storage.

Silicon/graphite composites show a high specific capacity and improved cycling stability. However, the intrinsic difference between silicon and graphite, such as unequal volume expansion and lithium-ion diffusion kinetics, causes persistent stress at the silicon/graphite interface and the expansion of the electrical isolation region. Herein, carbon nanotubes (CNTs) were successfully introduced into silicon/carbon composites via ball milling and spray drying, which effectively relieved the stress concentration at the direct contact interface and formed a three-dimensional conductive structure. In addition, CNTs and amorphous carbon acting as "lubricants" further improved the inherent differences between silicon and graphite. As a result, the Si/CNTs/G@C-1 anode increased the cycling performance and rate capability, with a reversible capacity of up to 465 mAh g-1 after 500 cycles at 1 A g-1 and superior rate performance of 523 mAh g-1 at 2 A g-1. It is believed that this strategy may provide a feasible preparation of large-scale high-content silicon-based nanocomposite anodes in lithium-ion batteries.

Balancing Graphitic Nanodomains and Heteroatom Doping in Hard Carbons Toward High Capacity and Durable Potassium‐Ion Battery Anodes

AbstractHard carbons (HCs) have emerged as promising candidates for commercial anodes in potassium‐ion batteries (PIBs). However, a thorny challenge remains in achieving high reversible capacities at high charge/discharge rates, which significantly hinders the development of HCs for PIBs. Here, a temperature‐controlled strategy is proposed to effectively balance graphitic nanodomains and heteroatom doping content in HCs, resulting in widened carbon layer spacing, high conductivity, and abundant K‐ion intercalation sites. The optimized NO‐HC600 electrode exhibits a high reversible capacity of 315.0 mAh g−1 at 0.2 A g−1, and exceptional cyclic stability (235.0 mAh g−1 after 1200 cycles at 2.0 A g−1 with a capacity retention rate of 98.82%). Furthermore, systematic in /ex situ experiments unveil a highly reversible “adsorption–intercalation” mechanism governing potassium‐ion storage, confirming the origin of the superior performance. This work offers valuable insights into the facile preparation of HC anodes with high reversible capacity and fast charge/discharge capability for PIBs.

Reactive strontium nitride Additive: Constructing ion/electronic conductive paths for garnet-based solid-state lithium metal batteries

Solid-state lithium metal batteries (SSLMBs) using the garnet electrolyte Li6.4La3Zr1.4Ta0.6O12 (LLZTO) offer high safety and energy density compared to liquid organic electrolyte lithium-ion batteries. However, the interfacial electrochemical stabilization of Li metal anode with LLZTO leads to problems such as high interfacial resistance and Li dendrite growth, which hinders the wide application of SSLMBs. In this work, a multifunctional Li-Sr-N composite anode by mixing molten Li with Sr3N2 is constructed, in which the reactive wetting of in situ-formed Li3N achieves intimate interfacial contact, and the ionic/electronic conductive paths created by Li-Sr alloys and Li3N effectively homogenise Li deposition and suppress Li dendrites. The interfacial resistance is reduced to 40.42 Ω cm2, and the symmetric cell is stably cycled for 5500 h and 600 h at current densities of 0.1mA cm−2 and 0.4 mA cm−2, respectively, and the full cell of Li-Sr-N|LLZTO|LiFePO4 could be stably cycled for 200 cycles at 0.5C. The preparation of composite anodes using Sr3N2 as an additive may be a new strategy for producing of garnet-based SSLMBs with outstanding energy density and safety performance.

A Novel Gelatin Binder with Helical Crosslinked Network for High-Performance Si Anodes in Lithium-Ion Batteries.

Silicon(Si) is a promising anode material for lithium-ion batteries, but its large volume expansion during cycling poses a challenge for the binder design. In this study, a novel gelatin binder is designed and prepared with a helical crosslinked network structure. This gelatin binder is prepared by enzymatic crosslinking and immersion in Hofmeister salt solution, which induces the formation of network and helical secondary structures. The helical crosslinked network structure can be analogous to a spring group system to effectively dissipate the stress and strain caused by the Si expansion. The gelatin binder is further partially carbonized by low-temperature pyrolysis, which improves its conductivity and stability. The Sianode with the optimized gelatin binder exhibits high initial coulombic efficiency, excellent rate performance, and long-term cycling stability. This study provides an innovative approach for the preparation of high-performance Si anodes, namely by controlling the molecular configuration of the binder to significantly improve the cycle stability, which can also be applied to other high-capacity anode materials that suffer from large volume changes during cycling.

Sub-minute carbonization of polymer/carbon nanotube films by microwave induction heating for ultrafast preparation of hard carbon anodes for sodium-ion batteries

Hard carbons (HCs) are excellent anode materials for sodium-ion batteries (SIBs). However, the carbonization and granulation of HC powders involve complex processes and require considerable energy. Here, we developed a facile method for manufacturing HC anodes for SIBs via a novel microwave induction heating (MIH) process for polymer/single-walled carbon nanotube (SWCNT) films. Numerical simulations solving electromagnetic field and heat transfer problems revealed the MIH mechanism; the electric current induced by the applied microwave enables direct Joule heating of the SWCNT networks in the composite film. Consequently, the composite films could be heated to the target temperatures (800–1400 °C) and free-standing HC/SWCNT anodes could be prepared by applying MIH for only 30 s. Comparative analyses confirmed that ultrafast MIH is a reliable technique for producing HC anodes and can replace conventional carbonization processes which require a high-temperature furnace. Moreover, the HC/SWCNT anodes prepared by the ultrafast MIH were successfully applied to the SIB full cells. Finally, the feasibility of MIH for scalable roll-to-roll production of HC anodes was verified through local heating tests using a circular sheet larger than a resonator.

Adjusting Ion Diffusion Kinetics of Li Deposition Enabled by an Elastic Porous Melamine Sponge Host for Stable Lithium Metal Anodes.

Lithium (Li) dendritic growth and huge volume expansion seriously hamper Li-metal anode development. Herein, we design a lightweight 3D Li-ion-affinity host enabled by silver (Ag) nanoparticles fully decorating a porous melamine sponge (Ag@PMS) for dendrite-free and high-areal-capacity Li anodes. The compact Ag nanoparticles provide abundant preferred nucleation sites and give the host strong conductivity. Moreover, the high specific surface area and polar groups of the elastic, porous melamine sponge enhance the Li-ion diffusion kinetics, prompting homogeneity of Li deposition and stripping. As expected, the integrated 3D Ag@PMS-Li anode delivered a remarkable electrochemical performance, with a Coulombic efficiency (CE) of 97.14% after 450 cycles at 1 mA cm-2. The symmetric cell showed an ultralong lifespan of 3400 h at 1 mA cm-2 for 1 mAh cm-2. This study provides a facile and cost-effective strategy to design an advanced 3D framework for the preparation of a stable dendrite-free Li metal anode.

Mystical alkali metal flame: Sodiophilic insights into rapid preparation of the Na metal battery anode

Extensive research has explored the utilization of tin oxide (SnO2) as a sodiophilic reagent in sodium metal batteries. However, achieving rapid encapsulation of sodium has remained elusive, despite efforts such as converting a side reaction yielding a sodiophobic Cu-Sn alloy into sodiophilic SnO2 on the Cu current collector's surface. Notably, the presence of preserved crystal water in SnO2 has proven pivotal, as it initiates the formation of a plasma-like alkali metal flame, facilitating swift encapsulation of metallic sodium at 400 °C. Analysis through XPS and TEM tests unveiled the interaction between crystal water and liquid sodium metal, leading to rapid heat release. This phenomenon results in the generation of sodium metal vapor (>882.9 °C) and the extraction of oxygen atoms from SnO2, forming Na2O within an argon environment. Consequently, Na2O, produced by the reaction of sodium and SnO2 with crystal water as the inducer, plays a critical role in the rapid encapsulation of sodium metal. Furthermore, the synthesized sodium metal electrode exhibited exceptional stability in cycles and resistance to dendrites. This discovery provides valuable insights into the reaction mechanisms of sodiophilic sites in sodium metals, serving as a crucial guide for further research in the field.

ZIF-derived "cocoon"-like in-situ Zn/N-doped carbon as high-capacity anodes for Li/Na-ion batteries

Owing to the unique structure and physicochemical properties, including high specific surface area, self-doped N atoms, open pore structure and good chemical stability, zeolitic imidazolate frameworks (ZIFs) and their derivatives have been widely used in the field of energy storage. Here, a new type of "cocoon"-like Zn/N doped ZIF-derived porous carbon (Zn@N-C-800) is synthesized as an anode for lithium-ion batteries (LIBs) and sodium ion batteries (SIBs) through a one-step carbonization process using a novel Zn-ZIF as the precursor. In Zn@N-C-800, the "cocoon"-like disordered carbon skeleton is conducive to electrolyte infiltration, while the Zn/N doping can provide additional active sites for ion storage. Benefiting from these unique structural characteristics, Zn@N-C-800 achieves excellent electrochemical performances as anode for both LIBs and SIBs: an ultrahigh rate capability of 352 mAh g−1 can be delivered at 12.8 A g−1 for LIBs; an outstanding long-term cycling stability (312 mAh g−1 at 1 A g−1 after 2000 cycles) can be achieved for SIBs. This paper provides new ideas for the design and preparation of high-performance anodes for LIBs and SIBs.

Efficient synthesis and lithium storage performance of SiO2/TiO2 composite film anode by plasma electrolytic oxidation

SiO2/TiO2 composite films with different phase ratios have been successfully fabricated via the one-step plasma electrolytic oxidation (PEO) method in an alkaline electrolyte on Ti foil to obtain a binder-free anode for Li-ion batteries. The formed composite films present porous morphology of TiO2 with a uniform distribution of SiO2. The specific capacity can stabilize above 400 mAh/g at the current density of 100 μA cm−2 for 500 cycles, together with the apparent improved initial coulombic efficiency of 88.7 % and excellent rate capability, which arises from the peculiar structure and the synergic enhancement effect of SiO2 active materials and TiO2 matrix. This work provides an efficient and low-cost route for the preparation of Li-ion battery binder-free anodes and enriches the application of plasma electrolysis technology in energy field.

Statistical approach for the preparation of silicon-graphite anodes: The role of oxygen content and crystallite size on electrochemical performance

Increasing the overall performance of Si-based anodes is still challenging because of the influence of various parameters involved in the preparation processes. This study addresses this challenge by employing the design of experiment technique to assess the impact of ball milling parameters such as milling speed, time, ball to powder and medium to powder ratio on the properties of silicon/graphite (Si/Gr) powders, with a focus on their electrochemical performance. Si/Gr powders in 20:80 weight ratio and 4 factor - 2 level full factorial design were used to find the main effects and interactions. Crystallite sizes were calculated using the Scherrer equation, and span values were obtained from the particle size distribution (PSD) analysis. SEM analyses were carried out to check the microstructure of powders. Ultimately, regression equations were created with high adjusted R2 values for crystallite size (93%), contamination (92%), and span (91%), respectively. Optimization experiments were carried out using the created regression equations, and the models were verified. It was found that crystallite size obtained by XRD data is more reliable to assess powder properties on the performance instead of PSD because of the agglomeration at the particle level throughout the milling. Further milling experiments were performed to elaborate the role of oxygen content and crystallite size. Results showed that while initial capacity is strongly related to total oxygen content, decay in the first cycles is correlated to the crystallite size of the silicon powder.

Research and application progress of electrochemical water softening technology in China

The issues of scaling, pipeline corrosion, and the growth of sludge, bacteria, and algae within circulating cooling water systems have been consistently limiting the enhancement of production efficiency in enterprises. The trending new electrochemical water softening technology, with its environmentally friendly, high efficiency, and low energy consumption characteristics, offers a fresh approach to addressing the stable operation of industrial circulating water systems. This paper begins by detailing the mechanisms of active scale removal, sterilization, and algae control facilitated by electrochemical water softening technology. Subsequently, it compares and analyzes the crucial core components of electrochemical devices (including the selection and preparation of anode and cathode materials, as well as the power system). Furthermore, it introduces the main types and installation modes of electrochemical equipment available in the market. Additionally, it uncovers the key factors influencing the efficiency of electrochemical descaling and validates the impact of electrochemical water softening technology on industrial circulating water systems through illustrative examples. Lastly, the paper concludes by summarizing and forecasting the future development direction of this technology.

Engineering High-Performance Li Metal Batteries through Dual-Gradient Porous Cu-CuZn Host.

Porous copper (Cu) current collectors show promise in stabilizing Li metal anodes (LMAs). However, insufficient lithiophilicity of pure Cu and limited porosity in three-dimensional (3D) porous Cu structures led to an inefficient Li-Cu composite preparation and poor electrochemical performance of Li-Cu composite anodes. Herein, we propose a porous Cu-CuZn (DG-CCZ) host for Li composite anodes to tackle these issues. This architecture features a pore size distribution and lithiophilic-lithiophobic characteristics designed in a gradient distribution from the inside to the outside of the anode structure. This dual-gradient porous Cu-CuZn exhibits exceptional capillary wettability to molten Li and provides a high porosity of up to 66.05%. This design promotes preferential Li deposition in the interior of the porous structure during battery operation, effectively inhibiting Li dendrite formation. Consequently, all cell systems achieve significantly improved cycling stability, including Li half-cells, Li-Li symmetric cells, and Li-LFP full cells. When paired synergistically with the double-coated LiFePO4 cathode, the pouch cell configured with multiple electrodes demonstrates an impressive discharge capacity of 159.3 mAh g-1 at 1C. We believe this study can inspire the design of future 3D Li anodes with enhanced Li utilization efficiency and facilitate the development of future high-energy Li metal batteries.

Design Principle and Development Trends of Silicon-Based Anode Binders for Lithium-ion Batteries: A Mini Review

Abstract: Silicon (Si), recognized as a promising alternative material for the anodes of lithium-ion batteries, boasts a high theoretical specific capacity and abundant natural availability. During the preparation of silicon-based anodes, binders play a pivotal role in ensuring the cohesion of silicon particles, conductive agents, and current collectors. The structure and performance of these binders are critical for the mechanical stability, electrical conductivity, and stress dissipation capacity of the anodes. This review initially outlines the structural characteristics of various binders, including linear, branched, and three-dimensional cross-linked types. It then delves into the relationship between the structure and properties of these binders in the context of their application in high-performance lithium-ion batteries, focusing on their mechanical properties, electrical conductivity, and self-healing capabilities. Particular attention is given to the design strategies for binders that facilitate stress dissipation, with an emphasis on integrating multifunctional polymer binders renowned for their superior conductive and self-healing features. Such binders contribute to the formation of a robust three-dimensional network structure via multiple bonding mechanisms, including chemical, non-covalent, and coordination interactions. This configuration significantly enhances the adhesion between silicon particles, thereby facilitating the efficient dissipation of stress, which is a key aspect for ensuring the long-term cycling stability of lithium-ion batteries. Lastly, the paper explores future development directions for silicon anode binders, advocating for a thorough investigation into the synergy of diverse structural and functional combinations, with the aim of advancing the performance and practical application of silicon-based lithium-ion batteries.

Dual ligands and crosslinking atoms relayed MOF anode for tetracycline hydrochloride electrocatalytic decontamination: Efficiency and mechanism

MOF anodes were especially prepared with dual-ligand and S/N crosslinking atoms for tetracycline hydrochloride (TCH) electrocatalytic degradation. Results showed S(HTTP)-Ni-N(HAB) and N(HITP)-Ni-S(BHT) exhibited high electrocatalytic performance with 100% TCH degradation in 10 min, which were superior to that of S(HTTP)-Ni-S(BHT) and N(HITP)-Ni-N(HAB). The experimental and DFT calculation results jointly unraveled that the electron delocalization created by adjacent S/N crosslinking atoms facilitated the electron conduction and produced positive-charged Ni sites for the improved generation of ·O2− and ·OH radicals. The positive contributions of ·O2− and ·OH radicals then proved the degradation pathways of TCH. In addition, extended experiments on various conditions and pollutions highlighted the application potential of S/N hybrid MOF anodes. The final results provided new insight into MOF anode design and preparation via large cardinal ligand and crosslinking atom adjustment for environmental application.

Electrochemical preparation and characterization of a new configuration SnO2 anode and its application for treating petroleum refinery wastewater

In the present work, the feasibility of removing chemical oxygen demand (COD) from petroleum refiner wastewater (PRW) was examined through an anodic oxidation process using a SnO2-copper substrate anode in a prototype tubular batch electrochemical reactor. The SnO2 anode was prepared by cathodic deposition from a nitrate solution and characterized by techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM). Effects of current density, [Sn2+]/[HNO3] molar ratio, and time on the properties of the prepared anode were investigated. The XRD results showed that main peaks corresponded to deposition of tetragonal SnO2. Besides, broad peeks were observed indicating that the deposits have a lower degree of crystallinity. The results confirmed that increasing current density higher than 10 mA/cm2 results in formation of a mixture of SnO2 and Sn deposits. Additionally, the results proved that [Sn2+]/[HNO3] molar ratio has the main effect on the electrodeposition process, where keeping this ratio lower than 0.33 is recommended to ensure pure SnO2 film deposition. The best conditions for electrodeposition of SnO2 as a compact film on a copper substrate were a current density of 10 mA/cm2, [Sn2+] of 25 mM, [HNO3] of 125 mM to make a molar ratio of 0.2, and 30 min to confirm the formation of deposits without cracks and having an atomic percent (Sn/O) of 20.6/65. The application of the prepared anode for removing of COD from PRW confirmed a good performance with a removal efficiency of 79 % at current density of 12 mA/cm2, pH of 7.8, and operating time of 150 min in which an energy consumption of 9.93 kWh/kg COD was required. The degradation of COD using the SnO2 electrode was found to obey a pseudo first-order kinetic. The application of anodic oxidation using the new configuration of the SnO2 anode can be considered an eco-friendly process for treating wastewater, featuring easy scale-up to an industrial scale at high removal efficiency and lower cost.

Controllable Interface Engineering for the Preparation of High Rate Silicon Anode

AbstractSilicon (Si) is considered to be the promising candidate anode for the next generation of high‐energy‐density batteries. However, the poor initial coulombic efficiency (ICE) and rate performance severely hinder its commercial development. Here, fully exploits the 2D structure of photovoltaic silicon waste (PV‐WSi), combining with the advantage of controllable depositing layers offered by fluidized bed atomic layer deposition (FBALD), to simultaneously achieve high ICE and highrate performance of Si‐based anodes. The characteristic of Li+ embedding vertically into the plane direction of the 2D sheet‐like structure of PV‐WSi helps shorten the diffusion distance, alleviating the pulverization problem caused by volume expansion. FBALD is utilized to controllably deposit Li2O (≈1 nm) and TiO2 (≈4 nm) layers to compensate for the loss of Li sources, further suppressing the volume expansion of Si and isolating the side reactions between Si and electrolyte. The prepared Si@Li2O@TiO2 demonstrates ultrahigh ICE (90.9%) and outstanding rate performance (>900 mAh g−1 at a rate of 20 A g−1). Full cells with the Si@Li2O@TiO2 anode and LiFePO4 cathode deliver a stable capacity of 100 mAh g−1 after 300 cycles at 0.5 C. This work provides new ideas for the development of high ICE, high‐rate Si‐based anodes based on low‐cost photovoltaic waste.

Preparation and properties of porous silicon anode coated with nitrogen-doped carbon for lithium-ion battery

Preparation and properties of porous silicon anode coated with nitrogen-doped carbon for lithium-ion battery