Micron-sized SiOx/N-doped carbon composite spheres fabricated with biomass chitosan for high-performance lithium-ion battery anodes

To achieve superior lithium storage performance, SiO_x is usually designed into nanostructured SiO_x/C composites by complex or expensive methods. Here, micron-sized interconnected SiO_x/N-doped carbon (NC) microspheres composed of evenly dispersed SiO_x nano-domains and NC have been fabricated by a scalable microemulsion method and following pyrolysis, using vinyltriethoxysilane and chitosan as precursors. The unique structure of the micron-sized SiO_x/NC spheres leads to enhanced structural integrity and enables stable long-term cycling (800 cycles at 2 A g⁻¹). Benefiting from the enhanced electron/Li⁺ diffusion kinetics originated from the unique structure and N-doping, SiO_x/NC-2 presents considerable capacitive-controlled Li storage capacity, which leads to outstanding rate capability. Consequently, the assembled SiO_x/NC-2//LiFePO₄ full cell exhibits superior rate capability (106 mA h g⁻¹ at 4C) and stable long-term cycling at 2C (102 mA h g⁻¹ after 350 cycles). This work opens a new door for the application of chitosan in building micron-sized high-performance SiO_x/C anode materials, and to some extent facilitates the recycling of waste seafood shells.

Chitosan is employed as a carbon precursor to fabricate micron-scale interconnected SiO_x/NC spheres that exhibit excellent lithium storage performance.     

Nitrogen doped small molecular structures of nano-graphene for high-performance anodes suitable for lithium ion storage

N-doped nano-graphene derivatives were prepared by a bottom-up organic synthesis method. Through d-spacing modification and dynamic self-assembly of the structures of these molecules, ideal lithium ion-transfer aggregation formed between each monolayer. Rapid ion/electron transfer and maintenance of the structural integrity during repeated ion insertion/extraction occurred due to the lack of a covalent interaction force among the assembled structures. The doping level, i.e., number of N atoms, had a significant influence on the molecular self-assembled structures through hierarchical self-assembly. As the N concentration increased, the d-space between the nanosheets increased from 3.4 to 4.3. The capacity of the nano-graphene increased greatly from N-doping nano-graphene (NG-N₄) to 1800 mA h g⁻¹, indicating that the capacity is related to the structure. Moreover, the N-doping site of nano-graphene was defined and the relationship between the performance and structure was determined.

N-doped nano-graphene derivatives were prepared by a bottom-up organic synthesis method.     

Hierarchical assembly of ZnO nanowire trunks decorated with ZnO nanosheets for lithium ion battery anodes

Hierarchical architectures composed of nanomaterials in different forms are essential to improve the performance of lithium-ion battery (LIB) anodes. Here, we systematically studied the effects of hierarchical ZnO nanostructures on the electrochemical performance of LIBs. ZnO nanowire (NW) trunks were decorated with ZnO NWs or ZnO nanosheets (NSs) by successive hydrothermal synthesis to create hierarchical three-dimensional nanostructures. The branched ZnO NSs on the ZnO NW trunk exhibited a two-fold higher specific gravimetric capacity compared to ZnO NWs and branched ZnO NWs on ZnO NW trunks after 100 cycles of charging–discharging at 0.2C (197.4 mA g⁻¹). The improvement in battery anode performance is attributable to the increased interfacial area between the electrodes and electrolyte, and the void space of the branched NSs that facilitates lithium ion transport and volume changes during cycling.

Hierarchical architectures composed of nanomaterials in different forms are essential to improve the performance of lithium-ion battery (LIB) anodes.     

Improved pseudocapacitive charge storage in highly ordered mesoporous TiO2/carbon nanocomposites as high-performance Li-ion hybrid supercapacitor anodes

A Li-ion hybrid supercapacitor (Li-HSCs), an integrated system of a Li-ion battery and a supercapacitor, is an important energy-storage device because of its outstanding energy and power as well as long-term cycle life. In this work, we propose an attractive material (a mesoporous anatase titanium dioxide/carbon hybrid material, m-TiO₂-C) as a rapid and stable Li⁺ storage anode material for Li-HSCs. m-TiO₂-C exhibits high specific capacity (∼198 mA h g⁻¹ at 0.05 A g⁻¹) and promising rate performance (∼90 mA h g⁻¹ at 5 A g⁻¹) with stable cyclability, resulting from the well-designed porous structure with nanocrystalline anatase TiO₂ and conductive carbon. Thereby, it is demonstrated that a Li-HSC system using a m-TiO₂-C anode provides high energy and power (∼63 W h kg⁻¹, and ∼4044 W kg⁻¹).

A mesoporous TiO₂/carbon nanocomposite prepared by block copolymer self-assembly improves pseudocapacitive behavior and achieves high energy/power density Li-ion hybrid supercapacitors.     

Black titania nanotubes/spongy graphene nanocomposites for high-performance supercapacitors

A simple method is demonstrated to prepare functionalized spongy graphene/hydrogenated titanium dioxide (FG-HTiO₂) nanocomposites as interconnected, porous 3-dimensional (3D) network crinkly sheets. Such a 3D network structure provides better contact at the electrode/electrolyte interface and facilitates the charge transfer kinetics. The fabricated FG-HTiO₂ was characterized by X-ray diffraction (XRD), FTIR, scanning electron microscopy (FESEM), Raman spectroscopy, thermogravimetric analysis (TGA), UV-Vis absorption spectroscopy, and transmission electron microscopy (TEM). The synthesized materials have been evaluated as supercapacitor materials in 0.5 M H₂SO₄ using cyclic voltammetry (CV) at different potential scan rates, and galvanostatic charge/discharge tests at different current densities. The FG-HTiO₂ electrodes showed a maximum specific capacitance of 401 F g⁻¹ at a scan rate of 1 mV s⁻¹ and exhibited excellent cycling retention of 102% after 1000 cycles at 100 mV s⁻¹. The energy density was 78.66 W h kg⁻¹ with a power density of 466.9 W kg⁻¹ at 0.8 A g⁻¹. The improved supercapacitor performance could be attributed to the spongy graphene structure, adenine functionalization, and hydrogenated titanium dioxide.

A simple method is demonstrated to prepare functionalized spongy graphene/hydrogenated titanium dioxide (FG-HTiO₂) nanocomposites as interconnected, porous 3-dimensional (3D) network crinkly sheets.     

Sulfur-doped mesoporous carbon via thermal reduction of CS2 by Mg for high-performance supercapacitor electrodes and Li-ion battery anodes

This paper demonstrates a facile method based on vapor–solid reaction between magnesium powder and carbon disulfide vapor to produce S-doped porous carbon. The property of the as-prepared carbon is tunable by varying the synthesis temperature. The sample synthesized at 600 °C shows the highest specific surface area, suitable for supercapacitor electrodes. A high specific capacitance of 283 F g⁻¹ in H₂SO₄ aqueous electrolyte is achieved. The best performance of porous carbon for a Li-ion battery anode is obtained at the optimal temperature of 680 °C. Owing to the well-balanced soft and hard carbon compositions in the material, this porous carbon exhibits a high reversible capacity of 1440 mA h g⁻¹ and excellent rate performance.

This paper demonstrates a facile method to produce S-doped porous carbon by exploiting the reaction between magnesium and carbon disulfide for supercapacitor and Li-ion battery applications.     

Carbon-based artificial SEI layers for aqueous lithium-ion battery anodes

Replacing flammable organic electrolytes with aqueous electrolytes in lithium-ion batteries (LIB) can greatly enhance the safety of next-generation energy storage systems. With the extended electrochemical stability window of electrolytes, ‘water-in-salt’ (WIS) electrolytes containing LIB presented significant performance improvements. However, the solubility limits of lithium salts in water restrain the extent of kinetic protection offered by the high salt concentration. Here, we report design strategies of anode structure to improve the cycle life of LIB with WIS electrolytes. We introduced partially graphitic protective carbon layers on anode particles using a versatile coating method. This protective layer not only improved charge transfer kinetics but also minimized the exposure of anode surface for water electrolysis. The effectiveness of anode structure developed in this study was exemplified on TiO₂ anodes, where cycle performance and coulombic efficiency improved by 11 times and 29% respectively over the base anode material.

Artificial SEI layers passing lithium ions but blocking water molecules for long-lasting aqueous lithium-ion batteries.     

Two-phase interface hydrothermal synthesis of binder-free SnS2/graphene flexible paper electrodes for high-performance Li-ion batteries

Free-standing graphene-based composite paper electrodes with various active materials have attracted tremendous interest for next-generation lithium-ion batteries (LIBs) due to advantages such as their light weight, excellent mechanical flexibility, and superior electrochemical performance. However, despite its high theoretical energy density, SnS₂ is rather difficult to composite with the graphene paper, because conventional reduction procedures for graphene oxide (GO) induce either decomposition or oxidation of SnS₂. Herein, a novel solid/gas two-phase interface hydrothermal process is reported to fabricate flexible free-standing SnS₂/graphene nanocomposite papers (SGP) assisted by a reducing and stabilizing agent thioacetamide aqueous solution. Such hydrothermal process not only successfully reduces SnS₂/graphene oxide paper (SGOP) to SGP, but more importantly, keeps intact the paper configuration as well as the phase stability of SnS₂. The as-prepared SGP electrode exhibits high reversible discharge capacity, outstanding cyclic stability and rate capability, which can be attributed to the synergistic effect of the conductive and flexible graphene matrix for accommodation of the volumetric changes of SnS₂ upon cycling and the planar SnS₂ nanospacers between the graphene layers introducing nanopores for penetration of electrolyte and inhibition of graphene nanosheets restacking. This report demonstrates a new strategy for more active materials with promising lithium storage properties joining the flexible graphene-based paper electrode family.

Binder-free SnS₂/graphene flexible paper produced from a two-phase interface hydrothermal reaction with excellent electrochemical performance for lithium-ion batteries.     

Large-area growth of SnS2 nanosheets by chemical vapor deposition for high-performance photodetectors

Two-dimensional tin disulfide (SnS₂) is very popular in electronic, optoelectronic, energy storage, and conversion applications. However, the uncontrollable large-area growth of SnS₂ nanosheets and unsatisfactory performance of the photodetectors based on SnS₂ have hindered its applications. Here, we propose a chemical vapor deposition (CVD) method using SnCl₂ as a precursor to grow SnS₂ nanosheets. We found that the as-grown SnS₂ nanosheets were high-quality crystal structures. Then, photodetectors based on the as-grown SnS₂ were fabricated and, exhibited a high responsivity (1400 A W⁻¹), fast response rate (a response time of 7 ms and a recovery time of 6 ms), perfect external quantum efficiency (EQE) (2.6 × 10⁵%), and remarkable detectivity (D*) (3.1 × 10¹³ Jones). Our work provides a new CVD method to grow high-quality SnS₂ nanosheets.

Large-area SnS₂ nanosheets were grown through a CVD method by using SnCl₂ on SiO₂/Si substrates as the precursors. The SnS₂ nanosheets-based photodetectors shown high-performance.     

Curing behavior of sodium carboxymethyl cellulose/epoxy/MWCNT nanocomposites

The surfactant-assisted preparation of carbon nanotube (CNT)/polymer composites has attracted the attention of scientists around the world. Here, CNT/epoxy nanocomposites were prepared using sodium carboxymethyl cellulose (CMC). The effect of CMC on the curing behaviors of epoxy resin (E44) and CNTs/E44 was studied using differential scanning calorimetry (DSC). The curing kinetics of the CMC/CNTs/E44 systems were examined using methods where the activation energy (E) is a constant and where E is a variable, respectively. The change of E with the conversion (α) was calculated using the Starink isoconversional method. For the E44 system, a significant variation of E was observed when the conversion increased from 0.05 to 0.95. The E variable method was introduced to this system to describe this phenomenon. In contrast to the method where E is a constant, the E variable method has better agreement with the experimental data. With these two methods, the curing kinetics of the CMC/CNTs/epoxy system can be understood comprehensively and accurately. Ultimately, the dynamic mechanical properties of neat E44, CMC/E44 and CMC/CNTs/E44 were investigated and compared, which showed that CMC/E44 had a higher storage modulus (E_m) than the neat E44 and CMC/CNTs/E44 systems, and the CMC/CNTs/E44 system had a higher glass transition temperature (T_g) and damping factor (tan δ) than the neat E44 and CMC/E44 systems.

Kinetics calculated values and dynamic thermomechanical properties of CMC/CNTs/E44 systems.     

Fabrication of a composite anion exchange membrane with aligned ion channels for a high-performance non-aqueous vanadium redox flow battery

Fabrication of high-conductivity ion exchange membranes (IEMs) is crucial to improve the performance of non-aqueous vanadium redox flow batteries (NAVRFBs). In the present work, anion exchange membranes with high-conductivity were fabricated by aligning ion channels of the polymer electrolyte impregnated in porous polytetrafluoroethylene (PTFE) under electric fields. It was observed that the ion channels of the polymer electrolyte were uniformly orientated in the atomic-force microscopy image. Its morphological change could minimize detouring of the transport of BF₄⁻ ions. The results showed through-plane conductivity was improved from 12.7 to 33.1 mS cm⁻¹. The dimensional properties of the fabricated membranes were also enhanced compared with its cast membrane owing to the reinforcing effect of the substrate. Especially, the NAVRFB assembled with the optimized membrane showed increased capacities, with a 97% coulombic efficiency and 70% energy efficiency at 80 mA cm⁻². Furthermore, the optimized membrane made it possible to operate the NAVRFB at 120 mA cm⁻². Its operating current density was 120 times higher than that of a frequently used AHA membrane for RFBs.

Fabrication of high-conductivity ion exchange membranes (IEMs) is crucial to improve the performance of non-aqueous vanadium redox flow batteries (NAVRFBs).     

Vinyltriethoxysilane crosslinked poly(acrylic acid sodium) as a polymeric binder for high performance silicon anodes in lithium ion batteries

In order to effectively relieve the large volume changes of silicon anodes during the cycling process in lithium ion batteries (LIBs), we developed a vinyltriethoxysilane crosslinked poly(acrylic acid sodium) polymeric binder (PVTES-NaPAA) for the Si anodes. The PVTES-NaPAA binder was synthesized by using a free radical co-polymerization method with VTES and NaPAA as precursors. In this binder, NaPAA with carboxyl groups can provide strong adhesion between Si particles and the current collector. Furthermore, VTES can be hydrolyzed and condense with each other to form a three-dimensional crosslinked network; the special network makes it possible to improve the Si electrode stability, resulting in an excellent cycling performance (78.2% capacity retention after 100 cycles) and high coulombic efficiency (99.9% after 100 cycles).

The PVTES-NaPAA binder possesses a three-dimensional crosslinked network and exhibits an excellent cycling performance.     

Surface phosphation of 3D mesoporous NiCo2O4 nanowire arrays as bifunctional anodes for lithium and sodium ion batteries

A novel surface phosphate strategy was adopted to dramatically improve the charge transport, ion diffusion, electroactive sites, and cycle stability of mesoporous NiCo₂O₄ nanowire arrays (NWAs), drastically boosting their electrochemical properties. Consequently, the as-prepared phosphated NiCo₂O₄ NWA (P-NiCo₂O₄ NWA) electrode achieved excellent energy storage performance as a bifunctional anode material for both lithium ion batteries (LIBs) and sodium ion batteries (SIBs). When evaluated as an anode for LIBs, this P-NiCo₂O₄ NWA electrode showed a high reversible capacity up to 1156 mA h g⁻¹ for 1500 cycles at 200 mA g⁻¹ without appreciable capacity attenuation, while in SIBs, the electrode could also deliver an admirable initial capacity as high as 687 mA h g⁻¹ and maintained 83.5% of this after 500 cycles at the same current density. Most important, when the current density increased from 100 to 1000 mA g⁻¹, the capacity retention was about 63% in LIBs and 54% in SIBs. This work may shed light on the engineering of efficient electrodes for multifunctional flexible energy storage device applications.

A novel surface phosphate strategy was adopted to dramatically improve the charge transport, ion diffusion, electroactive sites, and cycle stability of mesoporous NiCo₂O₄ nanowire arrays (NWAs), drastically boosting their electrochemical properties.     

Control of cyclic stability and volume expansion on graphite–SiOx–C hierarchical structure for Li-ion battery anodes

To increase the energy density of today''s batteries, studies on adding Si-based materials to graphite have been widely conducted. However, adding a Si-based material in the slurry mixing step suffers from low distribution due to the self-aggregation property of the Si-based material. Herein, a hierarchical structure is proposed to increase the integrity by using APS to provide a bonding effect between graphite and SiO_x. Additionally, to endow a protection layer, carbon is coated on the surface using the CVD method. The designed structure demonstrates enhanced integrity based on electrochemical performance. The MSG (methane decomposed SiO_x@G) electrode demonstrates a high ICE of 85.6% with 429.8 mA h g⁻¹ initial discharge capacity. In addition, the MSG anode has superior capacity retention (89.3%) after 100 cycles, with enhanced volumetric expansion (12.7%) after 50 cycles. We believe that the excellent electrochemical performance of MSG is attributed to increased integrity by using APS (3-aminopropyltrimethoxysilane) with a CVD carbon coating.

This study demonstrates the increased integrity of graphite–SiO_x–C hierarchical structure using 3-aminopropyltrimethoxysilane (APS). Furthermore, the carbon coating contributes to elec-trode stability.     

3D plum candy-like NiCoMnO4@graphene as anodes for high-performance lithium-ion batteries

3D plum candy-like NiCoMnO₄ microspheres have been prepared via ultrasonic spraying and subsequently wrapped by graphene through electrostatic self-assembly. The as-prepared NiCoMnO₄ powders show hollow structures and NiCoMnO₄@graphene exhibits excellent electrochemical performances in terms of rate performance and cycling stability, achieving a high reversible capacity of 844.6 mA h g⁻¹ at a current density of 2000 mA g⁻¹. After 50 cycles at 1000 mA g⁻¹, NiCoMnO₄@graphene delivers a reversible capacity of 1045.1 mA h g⁻¹ while the pristine NiCoMnO₄ only has a capacity of 143.4 mA h g⁻¹. The hierarchical porous structure helps to facilitate electron transfer and Li-ion kinetic diffusion by shortening the Li-ion diffusion length, accommodating the mechanical stress and volume change during the Li-ion insertion/extraction processes. Analysis from the electrochemical performances reveals that the enhanced performances could be also attributed to the reduced charge-transfer resistance and enhanced Li-ion diffusion kinetics because of the graphene-coating. Moreover, Schottky electric field, due to the difference in work function between graphene and NiCoMnO_4, might be favorable for the redox activity of the NiCoMnO₄. In light of the excellent electrochemical performance and simple preparation, we believe that 3D plum candy-like NiCoMnO₄@graphene composites are expected to be applied as a promising anode materials for high-performance lithium ion batteries.

3D plum candy-like NiCoMnO₄ microspheres have been prepared via ultrasonic spraying and subsequently wrapped by graphene through electrostatic self-assembly.     

Facile synthesis of g-C3N4 quantum dots/graphene hydrogel nanocomposites for high-performance supercapacitor

This work demonstrates a facile one-pot method for preparing graphitic carbon nitride (g-C₃N₄) quantum dots/graphene hydrogel (CNQ/GH) nanocomposites using a hydrothermal process, in which graphene sheets of a graphene hydrogel (GH) are decorated with g-C₃N₄ quantum dots (CNQDs) and have a 3D hierarchical and interconnected structure through a typical self-assembly process. The obtained CNQ/GH nanocomposite demonstrates improved electrochemical performances of a supercapacitor with a specific capacitance of 243.2 F g⁻¹ at a current density of 0.2 A g⁻¹. In addition, the fabricated symmetric supercapacitor (SSC) using CNQ/GH electrodes exhibits a high energy density of 22.5 W h kg⁻¹ at a power density of 250 W kg⁻¹ and a superior cycling stability with a capacitance retention of 89.5% after 15 000 cycles. The observed improvements in the electrochemical performance of CNQ/GH electrodes are attributed to the large surface area with abundant mesopores and various C–N bonds in CNQDs, which promote efficient ion diffusion of electrolyte and electron transfer and provide more active sites for faradaic reactions. These obtained results demonstrate a facile and efficient route to develop potential electrode materials for high-performance energy storage device applications.

This work demonstrates a facile one-pot synthesis of graphitic carbon nitride (g-C₃N₄) quantum dots/graphene hydrogel (CNQ/GH) nanocomposites using a hydrothermal process, which shows excellent electrochemical performances for supercapacitors.     

Ultra-small Fe3O4 nanodots encapsulated in layered carbon nanosheets with fast kinetics for lithium/potassium-ion battery anodes

Iron oxides are regarded as promising anodes for both lithium-ion batteries (LIBs) and potassium-ion batteries (KIBs) due to their high theoretical capacity, abundant reserves, and low cost, but they are also facing great challenges due to the sluggish reaction kinetics, low electronic conductivity, huge volume change, and unstable electrode interphases. Moreover, iron oxides are normally prepared at high temperature, forming large particles because of Ostwald ripening, and exhibiting low electronic/ionic conductivity and unfavorable mechanical stability. To address those issues, herein, we have synthesized ultra-small Fe₃O₄ nanodots encapsulated in layered carbon nanosheets (Fe₃O₄@LCS), using the coordination interaction between catechol and Fe³⁺, demonstrating fast reaction kinetics, high capacity, and typical capacitive-controlled electrochemical behaviors. Such Fe₃O₄@LCS nanocomposites were derived from coordination compounds with layered structures via van der Waals''s force. Fe₃O₄@LCS-500 (annealed at 500 °C) nanocomposites have displayed attractive features of ultra-small particle size (∼5 nm), high surface area, mesoporous and layered feature. When used as anodes, Fe₃O₄@LCS-500 nanocomposites delivered exceptional electrochemical performances of high reversible capacity, excellent cycle stability and rate performance for both LIBs and KIBs. Such exceptional performances are highly associated with features of Fe₃O₄@LCS-500 nanocomposites in shortening Li/K ion diffusion length, fast reaction kinetics, high electronic/ionic conductivity, and robust electrode interphase stability.

Ultra-small Fe₃O₄ nanodots encapsulated in layered carbon nanosheet nanocomposites were synthesized, showing fast reaction kinetics, high conductivity, and robust stability.     

Novel hard carbon/graphite composites synthesized by a facile in situ anchoring method as high-performance anodes for lithium-ion batteries

In this report, novel hard carbon/graphite composites are prepared by a simple in situ particle anchoring method, followed by carbonization. The effects of loading content of hard carbon on the structure and electrochemical performance of the composites are investigated. The SEM results show that the hard carbon particles are anchored randomly on the surface of graphite. The electrochemical measurements demonstrate that an appropriate loading content of hard carbon can remarkably increase the specific reversible capacity of graphite, which is mainly contributed by lithiation in hard carbon, whereas excessive loading leads to the formation of a thick particle shell onto the surface of graphite, which deteriorates the initial coulombic efficiency drastically. Kinetic tests further show that excessive loading of hard carbon is unfavorable for lithium-ion diffusion probably due to the increased interface distance and decreased electroconductivity. The composite loaded with 10 wt% hard carbon exhibits balanced lithium storage performance with high reversible capacity of 366 mA h g⁻¹, high initial coulombic efficiency (∼91.3%), and superior rate capability and cycling performance. Thus, in this study, we suggest a facile and effective strategy to fabricate a promising graphite anode material for high-performance lithium-ion batteries.

A facile in situ surface anchoring process is proposed for the fabrication of novel hard carbon/graphite composites. Such unique composites can be used as promising anodes for lithium-ion batteries with high performance.     

Modified SiO hierarchical structure materials with improved initial coulombic efficiency for advanced lithium-ion battery anodes

Silicon-based anode materials are indispensable components in developing high energy density lithium-ion batteries, yet their practical application still faces great challenges, such as large volume change during the lithiation and delithiation process that causes the pulverization of silicon particles, and continuous formation and reformation of the solid electrolyte interfaces (SEI) which results in a low initial coulombic efficiency. As an endeavor to address these problems, in this study, Si/SiO/Li₂SiO₃@C structures were prepared via a facile method using SiO, pitch powder and Li₂CO₃/PVA solution followed by annealing treatment. The Si/SiO/Li₂SiO₃@C composite shows a great improvement in lithium storage where a high discharge capacity of 1645.47 mA h g⁻¹ was delivered with the 1^st C.E. of 69.05% at 100 mA g⁻¹. These results indicate that the designed method of integrating prelithiation and carbon coating for SiO and the as-prepared macro scale Si/SiO/Li₂SiO₃@C structures are practical for implementation in lithium-ion battery technology.

A simple method of prelithiation of SiO along with carbon coating to achieve high performance SiO-based materials.     

Alginic acid aquagel as a template and carbon source in the synthesis of Li4Ti5O12/C nanocomposites for application as anodes in Li-ion batteries

We report here a simple process for the synthesis of Li₄Ti₅O₁₂(LTO)/carbon nanocomposites by a one-pot method using an alginic acid aquagel as a template and carbon source, and lithium acetate and TiO₂ nanoparticles as precursors to the LTO phase. The carbon content can be tuned by adjusting the relative amount of alginic acid. The obtained materials consist of nanosized primary particles of LTO (30 nm) forming micron-sized aggregates covered by well-dispersed carbon (from 3 to 19 wt%). The homogeneous dispersion of carbon over the particles improves the electrochemical performance of LTO electrodes such as rate capability (>95 mA h g⁻¹ at 40C) and cycling performance (>98% of retention after 500 cycles at 5C), even with only 3% of carbon black additive in the electrode formulation. With a simple and easily up-scalable synthesis, the LTO/carbon nanocomposites of this study are promising candidates as anode materials for practical application in lithium-ion batteries.

We report here a simple process for the synthesis of Li₄Ti₅O₁₂(LTO)/carbon nanocomposites by a one-pot method using an alginic acid aquagel as a template and carbon source, and lithium acetate and TiO₂ nanoparticles as precursors to the LTO phase.