Assisted Synthesis Route Research Articles

Thermogravimetric/Thermal-Mass Spectroscopy Insight into Oxidation Propensity of Various Mechanochemically Made Kesterite Cu2ZnSnS4 Nanopowders.

Thermogravimetry coupled with thermal analysis and quadrupole mass spectroscopy TGA/DTA-QMS were primarily used to assess the oxidation susceptibility of a pool of nanocrystalline powders of the semiconductor kesterite Cu2ZnSnS4 for prospective photovoltaic applications, which were prepared via the mechanochemically assisted synthesis route from two different precursor systems. Each system, as confirmed by XRD patterns, yielded first the cubic polytype of kesterite with defunct semiconductor properties, which, after thermal annealing at 500 °C under neutral gas atmosphere, was converted to the tetragonal semiconductor polytype. The TGA/DTA-QMS determinations up to 1000 °C were carried out under a neutral argon Ar atmosphere and under a dry, oxygen-containing gas mixture of O2:Ar = 1:4 (vol.). The mass spectroscopy data confirmed that under each of the gas atmospheres, a distinctly different, multistep evolution of such oxygen-bearing gaseous compounds as sulfur oxides SO2/SO3, carbon dioxide CO2, and water vapor H2O was taking place. The TGA/DTA changes in correlation with the nature of evolving gases helped in the elucidation of the plausible chemistry linked to kesterite oxidation, both in the stage of nanopowder synthesis/storage at ambient air conditions and during forced oxidation up to 1000 °C in the dry, oxygen-containing gas mixture.

Optimizing performance: Achieving high capacitance and cycling durability in alkaline electrolyte with SnO2/SnSe||AC/KOH-based aqueous hybrid supercapacitor

A facile wet-chemical assisted synthesis route is adapted to prepare a novel SnO2/SnSe nanocomposite for the time to construct an aqueous asymmetric hybrid supercapacitor (AAHSC). The detailed characterization reveals the appropriate formation of micro flower-like SnO2-SnSe nanocomposite-covered with SnSe network to provide a conductive support and facilitate charge transport during the electrochemical processs. Compared with pure SnO2 micro flowers and SnSe electrodes, the SnO2-SnSe nanocomposite electrode delivers a brilliant charge storage performance. A rapid charge transport pathways was accomplished due to the lowest charge transfer resistance, resulting in a high capacitance and improved charge storage properties in an aqueous alkaline electrolyte solution with incredible reversibility and rate capability. Inspired by the excellent charge storage and capacitive properties, a two-cell mode-based AAHSC was built with SnO2-SnSe nanocomposite (cathode) and activated carbon (AC) as an anode (symbolized as SnO2-SnSe||AC/KOH) displayed the highest energy of 33.4 Wh/kg at a maximum power of 4003.7 W/kg, operating in a voltage of 1.6 V with excellent cycling stability of 89.5 %.

Oxidation in Ca/K-1144 iron-based superconductors polycrystalline compounds

Iron-based superconductors (IBSCs) are a class of material under investigation for the development of superconducting wires in the low-temperature-high magnetic fields power application. Among the various families of IBSCs, the 1144 CaKFe4As4 compound is a promising material able to achieve outstanding superconducting properties with a cheap and simple chemical composition. Oxidation, in these compounds, is considered an obstacle for high intergranular critical current density, Jc,GB. A study devoted to the evaluation of oxidation phenomena and their effects on the superconducting properties is thus needed in order to fully understand the involved mechanisms. From the evaluation of polycrystalline samples obtained by a mechanochemically assisted synthesis route, a degradation of the critical temperature and critical currents has been observed concurrently with oxygen accumulation at grain boundaries in open porosities. However, the crystalline structure at an atomic level seems not affected, as well as intragranular superconducting properties assessed by means of calorimetric methods. These results suggest that loss of superconducting properties in Ca/K-1144 compounds following oxidation is significantly associated with the worsening of grain connectivity.

Tailoring the critical temperature of Ca/K-1144 superconductors: the effect of aliovalent substitution on tetragonality

Among the iron-based superconductors, the so-called 1144 family has, in recent years, attracted significant interest due to its stoichiometric nature, with materials robust towards chemical inhomogeneities and characterized by a well-defined critical temperature. The most studied 1144 compounds are characterized by the A1AE1Fe4As4 chemical composition, where A and AE constitute an appropriate combination of alkaline and alkaline-earth metals, respectively. The 1144 structure is in fact formed only when the A and AE elements respect specific requirements in terms of relative size and parent compound structure. The stoichiometric aspect, one of their strong points, has represented, however, up to today a restriction, limiting the conceptualization of 1144 structures to quaternary compounds. In this work, we demonstrate that to obtain the 1144 crystalline phase it may be sufficient to maintain a 1:1 ratio between ions of different size that intercalate the Fe-As planes, and that in selected conditions an opportunely tailored cation substitution is possible. Using a simple mechanochemically assisted synthesis route 1144 compounds where Ca is substituted by Na, K by Ba, and both simultaneously, are obtained. We demonstrate that the critical temperature of doped compounds is not simply related to the substitution amount or to the resulting Fe valence. We show that the superconducting transition is in fact linked to the structural distortion induced by the chemical composition variation: by tailoring the chemical composition we obtain doubly substituted samples—with substitution levels up to 20%—characterized by a tetragonality ratio c/a similar to the pristine compound and critical temperatures of approximately 34 K.

Microwave-Assisted Synthesis and Characterization of Zeolite Prepared From South Africa Coal Fly Ash

In industry, synthetic zeolites are commonly used as ion-exchange materials, catalyst supports, and adsorbents. As a result, a more energy-efficient alternative for its synthesis from low-cost and accessible raw materials is needed. This study, presents the possibility of using class F South African coal fly ash (SACFA) from Lethaba thermal-power station as a precursor to produce zeolites via a microwave (MW) assisted synthesis route. The mineral content of synthetic materials was determined using X-ray florescence (XRF). Morphology was determined using a Scanning electron microscopy (SEM), elemental composition by energy dispersive spectrometer (EDS). X-ray diffractometry (XRD) was used to get structural characterization. Microwave (MW) irradiation time and intensity enhance the crystallization of the zeolite phase as a result of sufficient energy required to enable the solubility of alumina and silica from coal fly ash. The use of MW irradiation provides a green alternative to zeolite synthesis from fly ash (FA) than traditional thermal and fusion techniques, which uses a great deal of energy consumption and a longer reaction time.

Bio-surfactant mediated synthesis of Au/g-C3N4 plasmonic hybrid nanocomposite for enhanced photocatalytic reduction of mono-nitrophenols

A bio-surfactant assisted synthesis route has demonstrated in room temperature for decoration of gold nanoparticles (AuNPs) on g-C3N4 using Averrhoa carambola leaf extract towards mono-nitrophenol reduction under visible light irradiation. Biomolecules of the leaf extract and optimised reaction condition played a vital role on tuning the morphology and optoelectronic properties of AuNPs. The size of AuNPs were found to be 15 ± 3 nm on 2D g-C3N4 sheets by TEM and STEM-HAADF analysis. Among the designed plasmonic hybrid photocatalysts 3-wt% loaded AuNPs on g-C3N4 showed 99.01% of 4-nitrophenol, 97.70% of 3-nitrophenol and 98.50% of 2-nitrophenol photoreduction. The photocatalytic efficiency of Au/g-C3N4 was investigated under several parameters such as pH, initial nitrophenol concentration, and in presence of external inorganic anions. The mechanism of photoreduction of nitrophenol to aminophenol by Au/g-C3N4 was proposed based on the intermediate obtained from GCMS analysis. The observed higher catalytic activity of plasmonic hybrid photcatalysts is due to the synergic chemistry between the conduction band of g‐C3N4 and AuNP plasmonic band, which is well supported by PL, EIS, and transient photocurrent analysis. Kinetic rate constant for 3Au/g-C3N4 was found to be 0.43 min−1 at pH 3. Moreover, the rate of reaction significantly increased in presence of Cl−. ICP-OES analysis of as synthesised 3Au/g-C3N4 plasmonic photocatalyst shows there was no gold leaching even after ten cycles confirming the stability and reusability of the catalyst.

Critical Current and Pinning Features of a CaKFe4As4 Polycrystalline Sample.

We analyze the magnetic behavior of a CaKFe4As4 polycrystalline sample fabricated by a mechanochemically assisted synthesis route. By means of DC magnetization (M) measurements as a function of the temperature (T) and DC magnetic field (H) we study its critical parameters and pinning features. The critical temperature Tc has been evaluated by M(T) curves performed in Zero Field Cooling-Field Cooling conditions. These curves show the presence of a little magnetic background for temperatures above Tc, as also confirmed by the hysteresis loops M(H). Starting from the M(H) curves, the critical current density Jc of the sample has been calculated as a function of the field at different temperatures in the framework of the Bean critical state model. The Jc(H) values are in line with the ones reported in the literature for this typology of samples. By analyzing the temperature dependence of the critical current density Jc(T) at different magnetic fields, it has been found that the sample is characterized by a strong type pinning regime. This sample peculiarity can open perspectives for future improvement in the fabrication of this material.

Nano-crystalline Nd3+-doped LuPO4 optical materials obtained by ionic liquid assisted synthesis route

LuPO4 in the form of nano-powders can find potential application in bio-imaging and luminescence thermometry. To enable development of functional materials there is a need to acquire basic information about the effect of morphology and grain size on spectroscopic properties. So, we investigated a series of Nd3+-doped LuPO4 nanoparticles prepared with task-specific ionic liquid as the reactant and in-situ stabilizer. Thus, fast and facile preparation of the desired well-crystallized single-phase phosphate nanomaterials was possible. The XRD patterns and TEM analysis revealed the influence of the synthesis conditions on the morphology and nanoparticles size, which is reflected in their spectroscopic properties. Low-temperature high-resolution techniques i.e. absorption spectroscopy at 4.2 K and laser site-selective spectroscopy at 77 K with Nd3+ ion as structural probe were used. Micro-powdered Nd3+-doped LuPO4 obtained by a solid-state reaction was applied as a reference. The possible application of this material as an optical thermometer was considered.

Drug delivery and antimicrobial studies of chitosan-alginate based hydroxyapatite bioscaffolds formed by the Casein micelle assisted synthesis

The present study aims to develop a hydroxyapatite (HAP) based scaffold composite for orthopaedic applications and for that, we adopt a Casein (Cs) micelle assisted synthesis route for the formation of a composite. Following the synthesis and characterization of various fluorine (2% and 5%) substituted HAPs (FHAP), they have been tested for the release of Ciprofloxacin (CIP) drug and antimicrobial efficacy. The physicochemical characterization such as FTIR and Raman confirms the successful formation of the HAP composites. Similarly, the powder XRD and FESEM analysis have used for the confirmation of crystallinity and morphological behaviour, respectively. The elemental composition has confirmed using EDX analysis. The antimicrobial studies indicate that the 5% FHAP sample is possessing superior antifungal and antibacterial activities and the highest activity has been observed against the gram-positive bacteria (Staphylococcus aureus) with an inhibition zone of 47 mm while the gram-negative bacteria (Escherichia coli) has only 38 mm inhibition zone. The CIP drug release profile has been controlling with the Cs/5% FHAP sample. Therefore, this composite has carried out for the scaffold formation with the use of chitosan-alginate matrices. Further, characterization of chitosan-alginate/5% FHAP scaffold composite indicates porous, biodegradable, considerable water uptake and retention ability, along with the maintenance of controlled CIP drug-releasing properties. Based on the analysis, the as-synthesized chitosan-alginate/5% FHAP scaffold composite can be suitable for the biomedical and bioengineering applications of bone tissue growth and as an implant.

Solvothermal synthesis of carbon incorporated MnS2 Spheres; high sensing performance towards the detection of furazolidone in bio-fluids

Herein, we designed and synthesis a composite material consisting of manganese disulfide anchored on nitrogen-doped carbon spheres (MnS2@N-CS) as an electrode modifier, and their application to the detection of furazolidone (FUZ) was investigated. The integration of MnS2 and N-CS by solvothermal assisted synthesis route using inexpensive glucose as a carbon source as well as served as a nucleation center for the formation of MnS2. The morphology and crystalline structure of the MnS2@N-CS were well characterized by XRD, XPS, FESEM, HR-TEM, and EDX analysis. The electrochemical test of the MnS2@N-CS modified electrode shows an interesting electrochemical performance for the sensitive and selective detection of FUZ with a broad concentration range of 0.001–1590 µM and a lower detection limit (LOD) of 0.0041 µM. The enhancement in the catalytic activity of MnS2@N-CS can be attributed to the synergistic effect of MnS2 and N-CS, high electron transportation, and the unique spherical structure of MnS2@N-CS. The newly developed MnS2@N-CS sensor also displayed excellent sensitivity, repeatability, and reproducibility with a relative standard deviation (RSD) of 3.2%. Furthermore, the strong interaction between MnS2 and N-CS could help to succeed in the long-term stability of the sensor. Finally, this MnS2@N-CS sensor was successfully applied for the detection of FUZ in the biological sample and food samples such as human serum, urine, and milk with excellent recoveries.

Electrocatalytic performance of the cobalt oxide nanoparticles decorated graphene oxide over the detection of folic acid

Herein, we Design and synthesis of a composite material consisting of cobalt oxide anchored on graphene oxide (Co3O4@GO) as an electrode modifier, and their application to the detection of folic acid (FA) has been investigated. The integration of Co3O4 and GO is by hydrothermal assisted synthesis route. The morphology and crystalline structure of the Co3O4@GO has been well analyzed by XRD, XPS, FESEM, HR-TEM, and EDX analysis. The electrochemical test of the Co3O4@GO modified electrode shows an interesting electrochemical performance for the selective determination of FA with a broad concertation range of 0.1-4000 µM and a lower detection limit (LOD) of 0.024 µM. The enhancement in the catalytic activity of Co3O4@GO can be achieved by the synergistic effect of Co3O4and GO, high electron transportation, and unique spherical structure of Co3O4@GO. The newly developed Co3O4@GO sensor also displays excellent sensitivity of 47.23 µAµM−1 cm−2. Finally, this Co3O4@GO sensor is demonstrated for the detection of FA in the human urine sample with excellent recovery.

Polyol-mediated synthesis of La0.9Sr0.1Ga0.8Mg0.2O2.85-Ce0.85Sm0.15O1.925 composite electrolyte for IT-SOFCs

The Sr- and Mg-doped LaGaO3 (La0.9Sr0.1Ga0.8Mg0.2O2.85; LSGM) and Sm-doped CeO2 (Ce0.8Sm0.2O1.9; SDC) were synthesized by polyol assisted synthesis route. The composite of LSGM & SDC was prepared by their mixing in the weight ratio of 9:1, respectively. Its suitability as solid electrolyte was examined for electrochemical applications like solid oxide fuel cells (SOFCs). The structural, microstructural and most important electrical properties of the composite (LSGM-SDC) was studied by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Impedance spectroscopic (EIS) techniques. It was observed that the sintered LSGM-SDC composite comprises perovskite cubic LSGM phase mostly, with a minor SDC phase, as perceived by X-ray diffraction study. The LSGM-SDC composite electrolyte possess a small grain boundary and bulk resistance as compared to LSGM and SDC samples. In the measured temperature range, i.e. 500–700 °C, LSGM-SDC composite shows the highest conductivity as compare to LSGM and SDC systems. Thus, the composite processing of LSGM & SDC may result as an attractive approach for the preparation of solid electrolyte material for IT-SOFCs.

New synthesis route to kesterite Cu2ZnSnS4 semiconductor nanocrystalline powders utilizing copper alloys and a high energy ball milling-assisted process

Presented is a new mechanochemically assisted synthesis route to kesterite Cu2ZnSnS4 semiconductor for perspective photovoltaic applications. Initially, the combined copper Cu, zinc Zn, and tin Sn powders in atomic ratio 2:1:1 were subjected to high energy ball milling in a planetary ball mill under the highest reported to date rotation speeds of 900 and 1000 rpm to yield a definite nanopowder mixture of the copper intermetallic phases, i.e., γ Cu5Zn8-type and η’ Cu6Sn5-type of non-stoichiometric compositions. Upon addition of a suitable amount of sulfur S, the reactive milling was continued affording a pure sphalerite-type cubic phase tentatively called a pre-kesterite. As expected from our earlier research, this by-product did not exhibit any 65Cu and 119Sn MAS NMR spectra or clearly-defined absorption in the UV–vis range. The disordered and very much random Cu-Zn-Sn metal site occupation of all metal layers in the structure is proposed to account for the observed properties of pre-kesterite. The subsequent annealing under argon at temperatures around 500−550 °C resulted in the cubic phase conversion to the tetragonal phase of kesterite, prevailingly, by metal center reconfiguration into distinct Cu-Sn and Cu-Zn layers accompanied by crystal growth/particle recrystallization. The micro-Raman spectra were consistent with similar bonding and lattice phonon characteristics in both related materials. The XPS data confirmed the same oxidation states and comparable energy level characteristics of the constituent elements. The annealed nanocrystalline powders showed the anticipated 65Cu and 119Sn MAS NMR features, while supporting remnant paramagnetism, and UV–vis semiconducting characteristics of the target kesterite.

Ni/SnO2 xerogels via epoxide chemistry: potential candidate for H2S gas sensing application

We report a versatile epoxide assisted synthesis route of developing Ni/SnO2 xerogels and their use as efficient H2S gas sensors. Instead of expensive, non-aqueous and complicated organometallic precursors, epoxide route utilizes easy to handle salts as precursors (tin and nickel nitrates, in the present case) and epoxide (propylene oxide, in the present case) as a gelation agent. The obtained Ni/SnO2 xerogels with 1–4 mol% Ni doping, were analyzed using various physico-chemical techniques such as XRD, FE-SEM, TEM/HRTEM, EDAX, UV–Vis and FTIR spectroscopy. The developed nanomaterials showcase excellent physico-chemical as well as H2S gas sensing properties. Amongst the Ni doped SnO2 xerogels, 3 mol% Ni/SnO2 exhibited enhanced H2S response (from Ra/Rg value 5 to 11.5), and reduction in the operating temperature (from 325 to 275 °C). It showed a quick response of ~ 15 s and recovery within ~ 30 s. Almost 80.50% of its original efficiency after 60 days of shelf life, was exhibited with high stability. The developed route of Ni/SnO2 xerogels proved its design for efficient H2S gas sensing, and have considerable potential for industrial use.

Peanut shell biotemplate to fabricate porous magnetic Co3O4 coral reef and its catalytic properties for p-nitrophenol reduction and oxidative dye degradation

The biotemplate assisted synthesis route is environmentally friendly, cost effective and easy. It employs a biomaterial like fruit waste, vegetable waste, bio-macromolecule, etc. for attaining a specific morphology of the as-synthesized product. Herein, we report the novel synthesis of magnetic, coral-reef like spinel-Co3O4 nanoparticles (m-Co3O4 NPs) by the immersion-calcination technique using peanut peel as a biotemplate. The as-synthesized material has been characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), Brunauer–Emmett–Teller (BET) and X-ray photoelectron spectroscopy (XPS) analyses, which revealed the magnetic nature and spinel structure of coral-reef-like m-Co3O4 NPs possessing a high surface area (103 m2/g). The synthesized m-Co3O4 NPs have been successfully used as nanocatalysts for the reduction of para-nitrophenol to para-aminophenol in the presence of NaBH4, as well as for the advanced oxidative degradation of the Orange G dye by using the environmentally benign oxone. The pseudo first order kinetics model was followed by both the reactions. The as-prepared nanocatalyst demonstrated high stability and easy recovery by an external magnet for successive use without any substantial loss in activity up to five consecutive cycles for both the reactions. Hence, m-Co3O4 NPs are potential candidates as catalysts in reduction as well as oxidation reactions, specially to obtain valuable products like amines that possess high industrial value and for the removal of toxic water pollutants like organic dyes.

Luminescence properties of nitrogen-rich Ca-SiAlON:Eu2+ phosphors prepared by freeze-drying assisted combustion synthesis

Nitrogen-rich Eu2+-doped Ca-α-SiAlON phosphors (Cam/2−xSi12−m−nAlm+nOnN16−n:xEu) were synthesized by a freeze-drying assisted combustion synthesis (CS) route. Fast-synthesized products with high purity and uniform particle morphology were confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The analysis of lattice parameters by comparison with empirical equations showed that the as-prepared phosphors had low oxygen content. A series of samples were prepared according to the stoichiometry of Cam/2−0.08Si12−mAlmN16:0.08Eu for further research. The influences of m value on the luminescence properties were investigated in detail. As m increased, a redshift phenomenon was observed in both the excitation and emission spectra. First-principle electronic structure calculations showed that the 3d energy level of Ca played an important role in the occurrence of the redshift phenomenon.

Insertion of binary LiCl-P2O5 glass between Li+ NASICON crystallites and its effect on controlling inter-grain transport

Li+ ion conducting glass-ceramic composites have been prepared from fine flakes of ion conducting binary oxide glass i.e. 2LiCl-P2O5 (LCPO) and nanograins of LiTi2(PO4)3 (LTP) using milling assisted synthesis route. The effect of variation of glass content and composition in the composite has been systematically investigated. Milling and heat treatment during glass-ceramic formation do not lead to any decomposition or formation of a new phase. As suggested by XRD, DSC and conductivity-temperature cycles, LCPO remains in glassy state in the composite. The tiny glassy flakes are seen to be homogenously embedded in between the LTP crystallites as confirmed by FESEM. The bulk (σbulk) and grain boundary (σGB) conductivity values have been found to be ~4 × 10−5 Ω−1 cm−1 and ~8 × 10−6 Ω−1 cm−1 at 100 °C for the glass-ceramic with 20(60LCPO)-80(LTP-18h) which are significantly higher than those of pristine LTP pellets prepared under similar sintering conditions. Ionic mobility measurements suggest that mobile Li+ ion concentration existing in glassy phase at the grain boundaries contribute significantly to inter grain transport. These glass-ceramics have been found to be thermally stable up to a temperature of ~300 °C. Cyclic voltammetry measurements obtained at 100 °C suggest good stability under different electrode configurations.

Microwave-assisted facile and rapid synthesis of layered metal hydroxide nanosheet arrays towards high-performance aqueous hybrid supercapacitors

Layered metal hydroxides (LMHs) have been extensively investigated due to their high surface area and excellent properties. However, rapid synthesis of LMHs, with desirable nanostructures and performance, is a challenging task. Herein, a novel microwave (MW)-assisted synthesis route is presented by employing household microwave oven to directly grow LMH nanosheet arrays (NSAs) on current collectors for binder-free electrodes in supercapacitors. Ni(OH)2 NSAs delivered a great capacitance of 2516 and 1273 F/g at 1 and 20 A/g, respectively. Furthermore, a Ni(OH)2//AC aqueous hybrid supercapacitor delivered a significantly large energy density up to 66.7 Wh/kg at 400 W/kg as well as good cycle stability of 85.2%. Moreover, the green and low-cost MW-assisted synthesis route can be adopted for other LMH NSAs, i.e., vertically aligned Cu2(OH)3NO3 NSAs. The excellent electrochemical performance of LMH NSAs can be attributed to the unique nanostructure, direct production of binder-free electrodes and highly efficient MW aqueous method. These results demonstrate the potential of MW-assisted synthesis process for facile and rapid production of LMH NSAs with a wide variety of applications.

Microwave synthesis of MoO3-reduced graphene oxide nanocomposite for high performance asymmetric supercapacitors

MoO3-reduced graphene oxide nanocomposite is synthesized in a facile, time-saving and environmental friendly microwave assisted synthesis route. The as-prepared samples, MoO3 and MoO3-reduced graphene oxide are characterized by XRD, Raman, XPS, SEM, and TEM. The characteristic studies have confirmed the formation of MoO3 and its composite matrix with reduced graphene oxide. The electrochemical studies are carried out in three-electrode set up, and in two-electrode configuration to find the suitability of the as-prepared material for asymmetric supercapacitor applications. The galvanostatic charge/discharge profile of rGO//MoO3–rGO exhibits an excellent electrochemical activity with a specific capacitance of 133.68 F g−1 at 3 A g−1 with energy density and power density of 36.2 Wh Kg−1 and 535.6 W Kg−1 respectively. The asymmetric supercapacitor device attains 85% of cyclic stability even after 4000 charge/discharge cycles.

Three-dimensional nanocomposites with Co3O4 nanosheets parallelly embedded in carbon network walls for enhanced lithium-ion storage.

Three-dimensional Co3O4/C nanocomposites are synthesized via a hydrogel assisted synthesis route. The carbon has a three-dimensional interconnected network structure, and ultrathin Co3O4 nanosheets (≈5.0 nm) are parallelly and uniformly embedded in the two-dimensional carbon network walls. This unique structure restricts the aggregation and pulverization of active materials, and ensures the continuity and efficiency of electron and ion transmission during the lithiation/delithiation process. As a result, the Co3O4/C nanocomposites exhibit excellent cycling performance at different current densities. The discharge capacities remain at 905 mA h g-1 after 190 cycles at the current density of 100 mA g-1 and 561 mA h g-1 after 500 cycles at the current density of 2000 mA g-1. Since this approach is facile and large-scale, it is a rational way to engineer high capacity anodes to achieve improved electrochemical performances.