Facile Ball Milling Research Articles

Fe-Al bimetallic oxides functionalized-biochar via ball milling for enhanced adsorption of tetracycline in water

The clusters formed by modified materials on its surface makes the application of functionalized biochars in adsorption face a great challenge. Here, a facile ball milling technology was innovatively proposed to tailor Fe-Al oxides-laden bagasse biochar to fabricate a novel adsorbent (BMFA-BC). Benefited from the increased exposure of Fe-Al oxides and, more importantly, enhanced functional groups by ball milling, the adsorption capacity of BMFA-BC for aqueous tetracycline reached up to 116.6mgg-1 at 298K. And the adsorption performance was temperature-dependent. Characterization analysis, batch sorption (thermodynamics, kinetics, isotherms, chemical factors) as well as data modeling illustrated that this superior adsorption ability could be attributed to π-π conjugation, H-bonding, complexation as well as pore filling. BMFA-BC displayed good adsorption capacity in multiple aqueous environments. The excellent regeneration ability, magnetic susceptibility ensured its viability for sustainable pollutants removal. These superiorities revealed that BMFA-BC was a suitable sorbent for antibiotics elimination.

Trash to treasure: Green synthesis of novel Ag2O/Ag2CO3 Z-scheme heterojunctions with highly efficient photocatalytic activities derived from waste mussel shells

A novel Ag 2 O/Ag 2 CO 3 Z-scheme heterojunction derived from waste mussel shells was constructed by in-situ ion exchange process driven by ball milling, which “One Stone Two Birds” realized the “control of waste by waste” for efficient degradation of pollutants and “trash to treasure” for high value reutilization of waste mussel shells. • Novel Ag 2 O/Ag 2 CO 3 heterojunctions were constructed with mussel shells as precursors. • The composition of products can be in-situ regulated in the ion exchange process. • Ag 2 O/Ag 2 CO 3 -M showed a remarkable photocatalytic ability and stability. • Z-scheme heterojunction and OVs promoted the separation of photoinduced charges. • Waste mussel shells were reutilized with high value in removing hazardous substance. Shells, valuable renewable natural resources with particular mechanical properties and structures, are mostly abandoned as waste and accumulated in environment, leading to serious pollution and resource waste. To realize the high value reutilization and environmental protection, here, novel Ag-based photocatalysts were in-situ fabricated via a facile ball milling method using waste mussel shells as precursors for the first time. The composition, structure and photocatalytic activity of the obtained Ag-based photocatalysts can be regulated by the alkalinity of the reaction system caused by different treatments towards mussel shells. Among the obtained products, the Ag 2 O/Ag 2 CO 3 Z-scheme heterojunctions with massive oxygen vacancies displayed the strongest visible-light photocatalytic ability and superior reusability in degrading sulfadiazine, which can be attributed to the wider light response region and faster separation of photoinduced charge carriers. Besides, the photocatalytic mechanism was speculated according to the tests of radicals trapping, electron spin resonance and simulation calculations, verifying the charge transfer direction and chief roles of ·O 2 - and h + during the photocatalytic reaction. Above all, this study not only provides a convenient in-situ solid-state strategy to construct novel Ag-based photocatalysts with excellent photocatalytic activity, but also opens up a new perspective towards high value reutilization of waste shells in environmental remediation, “One Stone Two Birds” realizing the “control of waste by waste” and “trash to treasure”.

Room Temperature Halide-Eutectic Solid Electrolytes with Viscous Feature and Ultrahigh Ionic Conductivity.

A viscous feature is beneficial for a solid electrolyte with respect to assembling solid-state batteries, which can change the solid-solid contacts from point to face. Here, novel halide-based deep eutectic solid electrolytes (DESEs) prepared by a facile ball milling method is reported. The mixture of halides triggers the deep eutectic phenomena by intermolecular interactions, leading to diverse morphologies and viscous statuses in terms of composition. Chemical- and micro-structure analyses via the cryogenic technique reveal that the LiCl and LiF nanoparticles are dispersed in an amorphous halide matrix, which endow freely mobile ions for fast ion transport. The optimized DESE thus achieves low activation energy and high ionic conductivity of 16 mS cm-1 at room temperature, one of the highest values among various electrolytes so far. By integrating with the active materials to form a composite cathode, the viscous DESE yields a super-dense composite pellet which possesses intensively enhanced ionic conductivity in contrast to those formed by the sulfide-based electrolyte additives, demonstrating an attractive application prospect.

A facile strategy to convert low-activity commercial iron oxides and cobalt disulfide into high-activity Fenton-like catalysts: spontaneous generation of 1O2 for aqueous decontamination

Developing highly efficient, steady, and cost-effective heterogeneous catalyst for the in situ production of singlet oxygen ( 1 O 2 ) is the key challenge to advanced oxidation processes. Previous studies usually involve demanding reaction conditions, cumbersome preparation processes, or hazardous chemicals. Herein, a facile ball milling procedure is adopted to design a vacancy-rich iron–cobalt bimetallic heterojunctions (b-CoS 2 /Fe 3 O 4 ) catalyst with a core–shell structure, which can convert various inefficient commercial iron oxides and cobalt disulfide into highly active catalysts for dioxygen activation. Both experiment and DFT calculations show that the direct interfacial interaction between the CoS 2 and iron oxides, which is introduced by the ball milling, regulates the bond energy of Fe–O, contributing to the excellent reactivity toward molecular oxygen activation. As a result, in the absence of electricity, light, and other oxidants, the strong interaction between CoS 2 and Fe 3 O 4 enables the degradation activity of organic pollutants to be significantly enhanced. In addition, we design an automated reactor and apply it to wastewater treatment in continuous flow mode, further revealing the huge potential of the proposed system in environmental remediation. A novel heterogeneous catalyst (b-CoS 2 /Fe 3 O 4 ) decorated with sulfur vacancies (SVs) was fabricated through a simple, efficient, and large-scale ball milling procedure. The versatility of this strategy was proved by replacing Fe 3 O 4 with other iron-based compounds, providing a constructive reference for assembling other green systems for 1 O 2 self-production. • b-CoS 2 /Fe 3 O 4 was fabricated by facile ball milling. • b-CoS 2 /Fe 3 O 4 spontaneously produces 1 O 2 for efficient aqueous decontamination. • These novel advanced oxidation processes tolerate inorganic ions, dissolved organic matter, high salinity, and pH change well. • This strategy applies to fabricate heterostructured CoS 2 with various Fe-based species.

Facile Synthesis of Hybrid Anodes with Enhanced Lithium-Storage Performance Realized by a “Synergistic Effect”

Alloying-type anodes including Si- and Sn-based materials are considered the most exploitable anodes for high-performance lithium-ion batteries. However, problems of poor kinetics properties and structural failures such as grain pulverization and coarsening hinder their large-scale application. Herein, SnO2/Si@graphite hybrid anodes, with nano-SnO2 and nano-Si thoroughly mixed with each other and loaded onto graphite flakes, have been prepared by a facile ball milling method. Attributed to the "synergistic effect" between SnO2 and Si, the mechanical stability and kinetics properties can be remarkably enhanced. Furthermore, graphite substrate supplies a fast electrically conductive path and buffers the volume expansion of active particles. Accordingly, SnO2/Si@graphite delivers 798.9 mAh g-1 at 200 mA g-1 and maintains 550.8 mAh g-1 after 1000 cycles at 1 A g-1 in half cells. Impressively, a high energy density of 431.4 Wh kg-1 (based on the mass of anode and cathode) can be obtained in full cells when paired with the NCM622 cathode. This work presents an effective strategy to exploit high-performance alloying-type anodes for LIBs by designing hybrid materials with multiple active components.

Ball mill-assisted synthesis of NiFeCo-NC as bifunctional oxygen electrocatalysts for rechargeable zinc-air batteries

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are the core of clean energy technology. Oxygen electrocatalysts based on earth-abundant metals are of prime importance. Trimetallic catalysts have demonstrated reliable activities but their average performance, difficult synthesis techniques, and high synthesis costs limit their widespread use. Herein, the facile ball milling technique is introduced as an efficient and low-cost method for the synthesis of catalysts based on trimetallic NiFeCo nanometer-scale particles distributed over a CNT-graphene-like (NiFeCo-NC) structure. NiFeCo-NC is synthesized instantaneously from ball milling of melamine with industrial carbon nanotubes (CNTs) along with trimetallic particles. Results demonstrate that the NiFeCo-NC2 catalyst, synthesized from 2 g of melamine per 1 g of each metal salt, performed well in both ORR and OER. The potential difference between the half-wave reduction potential of the ORR (E 1/2 ) and the oxidation potential at 10 mA cm −2 (E 10 ) in OER reveals a better performance of the NiFeCo-NC2 as a bifunctional catalyst than other synthesized materials and reference catalysts. A zinc-air battery (ZAB) having the NiFeCo-NC2 catalyst performs better than the batteries using other catalysts. The NiFeCo-NC2 catalyst also exhibits excellent methanol tolerance, revealing its applicability for direct methanol fuel cell (DMFC) applications. Ball milling offers a simple, effective, versatile, and cost-effective mechano-chemical procedure for the concomitant one-pot mixing-synthesis of materials. • Catalysts based on trimetallic NiFeCo nanoparticles distributed over a CNT-graphene-like (NiFeCo-NC) structure. • A simple and cost-effective ball milling method for synthesis of NiFeCo-NC catalysts. • NiFeCo-NC catalysts revealed reliable performances as a bifunctional OER- ORR catalyst. • A long-term cycling stability in rechargeable Zn-air battery was confirmed. • NiFeCo-NC catalyst exhibited excellent methanol tolerance.

Ball-milled Bi2MoO6/biochar composites for synergistic adsorption and photodegradation of methylene blue: Kinetics and mechanisms

The adsorption of reactants is highly correlated with photocatalysis. Improving the adsorption ability of photocatalyst may realize highly efficient removal performance. In this work, Bi 2 MoO 6 and bamboo-derived biochar composite was developed by a facile ball milling method. The adsorption and photodegradation abilities of the composites were evaluated by removing methylene blue (MB), which is a most commonly used aromatic-cationic dye. The maximum adsorption capacity of MB on the optimized 20 % Bi 2 MoO 6 /biochar sample was 160.6 mg/g, and the synergistic adsorption-photocatalytic removal efficiency of MB reached 93.3 % within 30 min, which were superior to Bi 2 MoO 6 (13.3 mg/g, 31.6 %) and biochar (127.7 mg/g, 69.8 %). Compared to Bi 2 MoO 6 , the Bi 2 MoO 6 /biochar composites showed decreased bandgap and enhanced charge separation efficiency. The strong interfacial interactions between Bi 2 MoO 6 and biochar in composites facilitated the photo-induced electrons transfer. Furthermore, the photodegradation efficiency enhanced along with the adsorption efficiency while pH value increased, which further proves the synergy between adsorption and photodegradation. Noticeably, the 20 % Bi 2 MoO 6 /biochar can completely remove MB at pH between 3 and 11. This work proves Bi 2 MoO 6 modified biochar prepared by ball milling is a promising material for synergistic adsorption and photodegradation removal of organic pollutants. • The optimized 20 % BMO/BC had the maximum adsorption capacity of 160.6 mg/g. • The 20 % BMO/BC showed high MB removal efficiency under light (99.7 %, 60 min). • Removal kinetics were applied to analyze the processes under light or dark. • Synergistic adsorption and photodegradation removal mechanism was elucidated. • Biochar promoted photo-inducted charges transfer in composites.

Ball-milled bismuth oxychloride/biochar nanocomposites with rich oxygen vacancies for reactive red-120 adsorption in aqueous solution

Fabricating surface oxygen vacancies is considered to be an efficient method to improve the adsorption performance of sorbents. In this work, a bismuth oxychloride/biochar (BiOCl/BC) nanocomposite with abundant oxygen vacancies was successfully prepared by a facile ball milling method. BiOCl/BC nanocomposite was found to have excellent adsorption performance for removing reactive red-120 (RR120) from aqueous solution. The effects of key adsorption parameters, such as RR120 dye concentration, solution pH (2–10), and contact time were studied by batch adsorption test. The adsorption data were well described by the Langmuir and Freundlich isotherms and pseudo-second-order kinetic models. The 50%-BiOCl/BC (50 wt% of BiOCl in composite) exhibited the best adsorptive performance (60%), much better than the pristine BM-BC (20%). The high adsorption capacity of 50%-BiOCl/BC (Langmuir maximum capacity of 116.382 mg g−1) can be attributed to the electrostatic effect, π–π interactions, and hydrogen bond. This work provided a facile method to prepare semiconductor assisted biochar-based adsorbents, which would also contribute to the advance of environmental remediation.Graphical abstract

Pyridinic nitrogen enables dechlorination of trichloroethylene to acetylene by green rust: Performance, mechanism and applications

Carbonous materials were found to catalyze the dechlorination of trichloroethylene (TCE) by green rust (GR), but the catalytic mechanism was not fully understood. We have developed a facile ball milling method to synthesize N-doped graphene (NG) with various N species, catalyzing fast dechlorination of TCE to acetylene by GR with the highest acetylene production rate of ~0.1 d-1. The adsorption of TCE onto NG is mainly derived from the graphene region of NG, and high pyridinic N is essential for the enhanced TCE reduction by GR. Oxygen species did not enhance the TCE reduction in GR/NG system. High dechlorination rates are correlated to a high amount of defect in NG and a high electron conductivity of NG. Pyridinic N has the highest adsorption energy for TCE among all the N species, which leads to the highest catalytic performance. High electrochemically active surface area resulted from the high content of pyridinic N facilitate the NG-catalyzed dechlorination. The acetylene production rate in real groundwater is still around one-third of that in ultrapure water. This work not only reveals the catalytic mechanism of NG-catalyzed dechlorination by GR, but also provide a feasible approach for practical remediations of TCE-contaminated groundwater using GR-NG mixture.

Ball-milled bismuth oxybromide/biochar composites with enhanced removal of reactive red owing to the synergy between adsorption and photodegradation

In this paper, bismuth oxybromide (BiOBr)/biochar composites were synthesized by a facile ball milling method for synergistic adsorption and photodegradation of Reactive red 120 (RR120). The characterizations show that ball milling changed the degree of crystallization, increased the surface area, and promoted the charge transfer ability of biochar. The 70% BiOBr/BC composite showed the best removal efficiency for RR120 removal with or without light illumination, which proves its enhanced removal ability by adsorption and photodegradation. The biochar is served as a support of BiOBr for preventing its aggregation and a transporter of charges for promoting the separation of photo-induced carriers in composites. BiOBr can release the adsorption sites on the surface of composites by degradation, which facilitated the RR120 removal and regenerated the photocatalyst for reusing. The strong interactions between BiOBr and biochar in composites resulted from ball milling were beneficial for the charge transfer and synergistic removal of adsorption and degradation. Findings of this work indicate that ball milling method is an effective method to prepare highly efficient biochar-based composites for RR120 removal through synergistic adsorption and photodegradation.

Ball milling synthesis of porous g-C3N4 ultrathin nanosheets functionalized with alkynyl groups for strengthened photocatalytic activity

Porous g-C 3 N 4 ultrathin nanosheets functionalized with alkynyl groups were fabricated by a facile ball milling method and the improved photocatalytic reduction of N 2 as well as degradation of Rhodamine B and levofloxacin were demonstrated. • Alkynyl functionalized g-C 3 N 4 are synthesized via ball milling of CaC 2 and g-C 3 N 4 . • The resulted g-C 3 N 4 nanosheets exhibits ultrathin wrinkled structure with abundant pores. • Enhanced light response, carriers seperation, and more active sites are analyzed. • Improved photocatalytic N 2 fixation and contaminants degradation are confirmed. • The improved photocatalytic redox activity is a consequence of multiple factors. Herein, the alkynyl groups are grafted on g-C 3 N 4 via ball milling of g-C 3 N 4 and CaC 2 . The successful functionalization of g-C 3 N 4 by alkynyl is demonstrated by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Ultrathin wrinkle-like structure with abundant pores is observed for the resulted alkynyl functionalized g-C 3 N 4 nanosheets, which can furnish abundant photocatalytic active sites. The photocatalytic NH 3 production rate of 0.12 mmol·g cat -1 ·h −1 is gained for alkynyl functionalized g-C 3 N 4 under UV–visible irradiation, which is 2.0-folds higher than pristine g-C 3 N 4 (0.058 mmol·g cat -1 ·h −1 ). A maximum of 1.9 and 1.5 folds enhancements are achieved for the photodegradation of rhodamine B and levofloxacin over functionalized g-C 3 N 4 compared to pristine g-C 3 N 4 . The improved mechanism is investigated by linear sweep voltammetry, transient photo-current, Tafel plots, electrochemical impedance spectroscopy, Mott-Schottky curves, turnover frequency, transient decay time, photoluminescence spectra, etc. The modification technique proposed in this paper can also be adopted to prepare other alkynyl functionalized semiconductors for photocatalytic application.

Effects of Needle Coke Conductive Additive on the Performance of Graphite/Resin Composite Plates

AbstractIn this manuscript, the graphite/resin composite plates were prepared via a facile ball milling strategy. The needle coke (NC) as a conductive additive was studied on effects of treated by ball milling on the electrical conductivity, mechanical property of the composite plates. All the characterizations showed that after ball milling, the NC particles have smaller particle size, and more uniform particle size distribution, which enhanced the interfacial adhesion between particles and resin. Due to the difference in shape and size between the auxiliary conductive filler and flake graphite, the addition of NC particles can easily fill the gap between flake‐like graphite and phenolic resin. The uniform distribution of these fillers improves the cross‐linking density, and the conductive path was added between the flake‐like graphite and the resin, which improved the electric conductivity of composit plate from 26.32 S cm−1 to 149.23 S cm−1. Such a prominent performance was attributed to the synergistic effects between the uniformly incorporated NC and the graphite/resin composite adhesive system.

Facile Ball-Milling Strategy for Constructing Covalently Connected Black Phosphorus–MoO3–x Heterostructures for Enhanced Photocatalytic Hydrogen Evolution

Facile Ball-Milling Strategy for Constructing Covalently Connected Black Phosphorus–MoO_3–<i>x</i> Heterostructures for Enhanced Photocatalytic Hydrogen Evolution

A facile and scalable Fe-Cr decorating strategy to boost the lithium storage of SiOx anode

SiOx is regarded as a promising anode material for the next-generation lithium-ion batteries with high energy density. However, the reduplicative volume changes during cycling cause the pulverizations of Si, leading to decreased utilization of active Si component and poor cycling performance. Herein, a facile and scalable Fe-Cr decorating strategy is reported to boost the lithium storage of SiOx anode. Our comprehensive characterizations indicate that there are strong interactions between Fe-Cr and SiOx during a facile ball milling process. After cycling, Fe-Cr nanoparticles are dispersed in the in-situ formed lithium silicates and Li2O matrix, which can maintain superior conductivity of lithium ion and electron for the active components through point-to-point connections. This unique structure boosts the electrochemical de-alloying process of the low-valent LixSi (0 ≤ x ≤ 2), and increases effective utilization of the active Si component during cycling, resulting in improvement of reversible capacity and cycling stability. This bm SiOx-FeCr electrode can deliver high reversible specific capacity (1370 m Ah g−1 at 200 mA g−1), good rate capability (653.8 m Ah g−1 at 2000 mA g−1), and superior cycling stability. This work provides a promising route for improving the utilization of active Si component and the structural stability of SiOx-based anodes.

Ball-milled magnetite for efficient arsenic decontamination: Insights into oxidation–adsorption mechanism

Conventional adsorbents for decontaminating arsenic exhibit low efficacy for the removal of arsenite (As(III)). This study aims to develop a robust As adsorbent from natural magnetite (M0) via a facile ball milling process, and evaluate their performance for decontaminating As(III) and As(V) in water and soil systems. The ball milling process decreased the particle size and crystallinity of M0, resulting in pronounced As removal by the ball-milled magnetite (Mm). Ball milling under air facilitated the formation of Fe-OH and Fe-COOH functional groups on Mm interface, contributing to effective elimination of As(III) and As(V) via hydrogen bonding and complexation mechanisms. Synergistic oxidation effects of hydroxyl and carboxyl groups, and reactive oxygen species (O2·-, and·OH) on the transformation of As(III) to As(V) during the adsorption were proposed to explain the enhanced As(III) removal by Mm. A short-term soil incubation experiment indicated that the addition of Mm (10wt%) induced a decrease in the concentration of exchangeable As by 30.25%, and facilitated the transformation of water-soluble As into residual fraction. Ball milling thus is considered as an eco-friendly (chemical-free) and inexpensive (scalable, one-stage process) method for upgrading the performance of natural magnetite towards remediating As, particularly for tackling the highly mobile As(III).

Facile Construction of Magnetic Ionic Liquid Supported Silica for Aerobic Oxidative Desulfurization in Fuel

With the rapid growth in fuel demand, deep desulfurization of fuel oil is vitally necessary for the sake of health and environmental protection. In this work, a kind of magnetic ionic liquid supported silica is prepared by a facile ball milling method, and applied in the aerobic oxidative desulfurization of organosulfurs in fuel. The experimental results indicated that ball milling procedure can increase the specific surface area of samples, which is beneficial to oxidative desulfurization process. Under the optimal reaction conditions, the prepared materials can have an entire removal of aromatic sulfur compounds as well as a good recycling ability. Moreover, the introduction of Fe3O4 did not decline the desulfurization performance, but help the catalyst to be easily separated after reaction.

Hydroxylated Graphene: A Promising Reinforcing Nanofiller for Nanoengineered Cement Composites.

A very low dosage of graphene oxide (GO) can enhance the mechanical durability of cement composites, but the reinforcing enhancement is highly dependent on the uniform dispersion of graphene in the matrix. Carboxylic groups at GO nanosheets have a decisive effect on GO aggregation in an alkaline cement solution because they have a strong complexation ability with aqueous Ca2+ released by cement hydration and subsequently crosslinks the adjacent graphene sheets, causing the immediate coagulation of GO. The available methods of homogeneously dispersing GO in a cement slurry cannot completely eliminate this carboxylic-crosslinking-induced GO coagulation. In this study, many hydroxyl groups were introduced onto the edge and planar nanosheets to prepare water-soluble hydroxylated graphene (HO-G) by facile ball milling. The structure of HO-G was thoroughly characterized in detail, and its dispersion behavior in pure water and Ca(OH)2 was extensively investigated. These results showed that the prepared HO-G exhibited good hydrophilicity and excellent colloidal dispersion ability against high pH and Ca2+ ions compared to GO. The effect of HO-G on the workability, mechanical strength, and chloride penetrability of a cement mortar was further studied. At a content of 0.03% by cement mass, HO-G provided 28.62 and 21.19% enhancements of compressive strength and 3.85 and 7.89% enhancements of flexural strength at 3 and 28 days, respectively, while the non-steady-state migration coefficient decreased by 31.51% compared to the reference mortar. Compared to GO, a lower dosage of HO-G exhibited a similar reinforcing effect to cement composites with little adverse impact on the fluidity of the fresh cement slurry. Moreover, the addition of HO-G could refine the pore structure, accelerate the hydration process of cement to some degree, and generate more hydration products so that the structure of the cement mortar was densified. Considering its environmentally friendly preparation, HO-G, as a promising reinforcing nanofiller, could provide a new solution to develop nanoengineered cement composites.

Facile ball milling preparation of sulfur-doped carbon as peroxymonosulfate activator for efficient removal of organic pollutants

Novel sulfur-doped activated carbon (SACx) particles were prepared by a facile ball milling process of a mixture of elemental sulfur and activated carbon (AC), and employed as activators of peroxymonosulfate (PMS) for the degradation of organic pollutants. The SACx/PMS system could efficiently degrade different pollutants including diethyl phthalate, bisphenol A, sulfamethoxazole, and phenol, achieving a degradation efficiency of 60–100% within 120 min. Increasing the S doping content favored PMS activation and pollutant degradation: the DEP degradation rate increased by 9 times as the S-doped content increased from 0 to 8.69 at%. EPR and radical quenching experiments suggested that • OH rather than SO 4 •− was the dominant reactive species for DEP degradation. The concentration of free radicals was strongly dependent on the content of C–S–C bonds, indicating that these linkages were the main active sites for PMS activation. This study provides a simple but effective strategy to improve the catalytic performance of carbon-based materials as PMS activators to degrade pollutants. • Sulfur-doped activated carbon materials (SACx) were prepared by ball milling. • The content of doped sulfur is facilely controlled. • SACx could efficiently activate PMS for pollutant degradation. • Rate of pollutant degradation increased by 9 times with sulfur-doped. • C–S–C bonds were the main active sites for PMS activation.

Graphite nano-modified SnO2-Ti2C MXene as anode material for high-performance lithium-ion batteries

• SnO 2 -Ti 2 C-C composite has been synthesized by hydrothermal and balling methods. • The ultrathin graphite nanosheet structure can facilitate lithium-ion transport. • Carbon coating can protect Ti 2 C from oxidation and self-stack. • The ternary SnO 2 -Ti 2 C-C composite can withstand high stress during cycling. • SnO 2 -Ti 2 C-C composite shows high rate and cycling stability. A SnO 2 -Ti 2 C-C nanoparticle composite anode was synthesized by using facile ball milling combined with hydrothermal treatment. The SnO 2 -Ti 2 C nanoparticles were homogeneously coated with graphite nanosheets by ball milling. Graphite nanosheets served as ideal volume expansion buffers and good electron conductors. Consequently, a high initial coulombic efficiency of 80.3% was displayed, and the system exhibited a high reversible capacity of 1036.87 mAh g −1 maintained after 200 cycles at 0.2 A g −1 , a rate capacity of 447.58 mAh g −1 at a high current density of 5.0 A g −1 , and long cycling stability with a capacity of 763.18 mAh g −1 after 500 cycles at 2.0 A g −1 . These results indicate that the incorporation of Ti 2 C, graphite nanosheets, and SnO 2 enhanced the performance of SnO 2 -based anodes for battery applications.

Nano-GeTe Embedded in a Three-Dimensional Carbon Sponge for Flexible Li-Ion and Na-Ion Battery Anodes.

Among the germanium-based compounds, GeTe is a promising anode candidate that exhibits high theoretical capacity (856 mAh g-1 vs Li+/Li and 401 mAh g-1 vs Na+/Na) and low volume expansion during an ion intercalation/deintercalation process. Nevertheless, achieving good dispersion of metal-like GeTe in anode materials remains a significant challenge. Herein, hybrid GeTe/graphene (GeTe/G) is proposed as a highly efficient anode for LiBs and SiBs by facile ball milling. Pulverized GeTe is effectively anchored on peeled graphene sheets that can accelerate Li+ transport in electrodes as predicted by theoretical calculations and thus result in improved overall electrochemical performance. For instance, GeTe/G possesses a high reversible capacity of 478 mAh g-1 under 0.1 A g-1 in the 300th cycle. Moreover, by further cross-linking the GeTe/G using carbon nanotube (CNT) and carbon nanofiber pyrolysis from cotton cellulose, the as-prepared three-dimensional (3D) flexible anode possesses macropores that acted as positive channels favorably for ion transport. Remarkably, the as-prepared flexible 3D GeTe/G/CNT electrode with a thickness of 1050 μm exhibits a high reversible capacity of 451.4 mAh g-1 (4.38 mAh cm-2) vs Li+/Li and 372.5 mAh g-1 (2.08 mAh cm-2) vs Na+/Na, respectively, in the second cycle under 0.1 A g-1. These results shed some light on the direct application of 3D flexible carbon sponge electrodes in high-performance LiBs/SiBs.