Carbon Composite Microspheres Research Articles

Hierarchical etching-assembly engineering of Fe-based composite microspheres with balanced magnetic-dielectric synergy towards ultrahigh electromagnetic wave absorption

Hierarchical engineering of magnetic-dielectric composite microspheres has attracted increasing attention owing to its potential to enhance electromagnetic wave absorption (EMA) through magnetic-dielectric synergy. However, optimizing magnetic-dielectric balance in composite microspheres at the nanoscale remains a formidable task due to their limited component optimization and microstructural regulation. Herein, a novel approach is proposed to modify conventional carbonyl iron powder (CIP) microspheres via synergistic etching-assembly strategy. By applying a polydopamine coating, successive tannic acid (TA) etching-assembly, and pyrolysis, hierarchical iron@carbon-1/N-doped carbon (Fe@C-1/NC) composite microspheres are obtained. This overcomes the drawbacks of CIP microspheres, including their high density and poor impedance matching, which hinder EMA performance. Hierarchical carbon layer engineering can introduce abundant dipole centers, heterogeneous interfaces, and conductive networks to induce dielectric loss, while magnetic components contribute to magnetic resonance and eddy current loss, as demonstrated by the results. Accordingly, Fe@C-1/NC composite microspheres demonstrate a minimum reflection loss (RLmin) of −70.7 dB and an effective absorption bandwidth of 3.75 GHz at a matching thickness of 2.3 mm. Generally, this work paves the way towards CIP engineering to provide guidance to the future exploration of hierarchical magnetic-dielectric EMA materials.

N, O-Doped Walnut-Like Porous Carbon Composite Microspheres Loaded with Fe/Co Nanoparticles for Adjustable Electromagnetic Wave Absorption.

This study addresses the challenge of designing simple and environmentally friendly methods for the preparation of effective electromagnetic wave (EMW) absorbing materials with tailored microstructures and multi-component regulation. N, O doped walnut-like porous carbon composite microspheres loaded with FeCo nanoparticles (WPCM/Fe-Co) are synthesized through high-temperature carbonization combined with soap-free emulsion polymerization and hydrothermal methods, avoiding the use of toxic solvents and complex conditions. The incorporation of magnetic components enhances magnetic loss, complementing dielectric loss to optimize EMW attenuation. The unique walnut-like morphology further improves impedance matching. The proportions of Fe and Co components can be adjusted to regulate the material's reflection loss, thickness, and bandwidth, allowing for fine-tuning of absorption performance. At a low filling ratio (16.7%), the optimal WPCM/Fe-Co composites exhibit a minimum reflection loss (RLmin ) of -48.34dB (10.33GHz, 3.0mm) and an overall effective absorbing bandwidth (EAB) covering the entire C bands, X bands, and Ku bands. This work introduces a novel approach to composition regulation and presents a green synthesis method for magnetic carbon composite absorbers with high-performance EMW absorption at low loading.

Synthesis of magnetic Cu-Fe3O4/carbon composite microspheres with excellent catalytic and antibacterial properties

Recently, metal nanoparticles supported on porous carbon microspheres have been attracted increasing attention from researchers worldwide. In this study, magnetically separable Cu nanoparticle-loaded porous Fe3O4/carbon microspheres (Cu-Fe3O4/C) were synthesized by combining one-step electrostatic droplets method with the impregnation adsorption and high-temperature carbonization approach. The structural properties of the as-prepared composite microspheres were systematically characterized. The results reveal a homogeneously distribution of the Cu and Fe3O4 nanoparticles in the carbon microspheres, which have an average diameter around 0.48 mm. In addition, the catalytic activity of the Cu-Fe3O4/C composite for selective reduction of 4-nitrophenol was investigated, and a high conversion of ca. 95 % was achieved within 30 min using the highly stable composite catalyst. Furthermore, in antibacterial tests, Cu-Fe3O4/C also showed significant suppression effects on bacteria such as Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Listeria monocytogenes (L. monocytogenes). These results demonstrate the high potential of the Cu-Fe3O4/C composite microspheres for catalytic and antibacterial applications.

Encapsulation of activated carbon into calcium alginate microspheres toward granular-activated carbon adsorbents for elemental mercury capture from natural gas.

Activated carbon (AC) is an effective adsorbent for removing environmental pollutants. However, the traditional powder form of AC shows difficulty in handling during application which widely limits its utilization on the industrial scale. Herein, to avoid such limitation, traditional AC powder was encapsulated into calcium alginate (CA) microspheres. Calcium alginate/activated carbon (CAA) composite microspheres were prepared via cross-linking of sodium alginate/activated carbon composite solutions in a calcium chloride solution. Furthermore, in order to boost adsorption affinity of CAA composite microspheres toward elemental mercury (Hg°), ammonium iodide (NH4I)-treated calcium alginate/activated carbon (NCA) composite microspheres were obtained by a simple impregnation method using NH4I treatment. The morphological, structural, and textural properties of the microspheres were characterized and their Hg° adsorptive capacity was tested at different temperatures. Interestingly, the maximum adsorption capacity of NCA adsorbent composite microspheres was determined as 36,056.5μg/g at a flow rate of 250mL/min, temperature of 25°C, and 500μg/Nm3 of Hg° initial concentration. The Gibbs free energy (ΔG°) for NCA adsorbent composite microspheres varied from - 8.59 to - 10.54kJ/mol indicating a spontaneous adsorption process with an exothermic nature. The experimental Hg° breakthrough curve correlated well with Yoon‒Nelson and Thomas models. The breakthrough time (tb) and equilibrium time (te) were found to be 7.5days and 23days, respectively. Collectively, the findings of this work indicate a good feasibility of using NCA composite microspheres as potential adsorbents for removing Hg° from natural gas.

Tailoring the shell thickness of yolk–shell structured carbon microspheres: applications in metal selenide and carbon composite microspheres for enhanced sodium ion storage properties

Herein, synthesis of nanostructured carbon yolk–shell, which have various thicknesses of the outer shell, are introduced. The optimized nickel–cobalt selenide–carbon yolk–shell exhibited excellent performance as a sodium-ion battery anode material.

Facile fabrication of Si-embedded amorphous carbon@graphitic carbon composite microspheres via spray drying as high-performance lithium-ion battery anodes

Silicon-nanoparticle-embedded amorphous carbon-graphitic carbon composite microspheres (denoted as Si/AC@GC) with numerous empty voids are synthesized using a spray drying process. Spray dried composite microspheres consisting of Si nanopowders, dextrin, and iron salt are transformed to uniquely structured Si/AC@GC microspheres via one-step carbonization followed by acid etching. The in situ formation of graphitic carbon with high electrical conductivity within the Si-C composite at a low carbonization temperature (700 °C) is achieved by applying a metallic Fe nanocatalyst. The Si/AC@GC microspheres exhibit higher electrochemical properties than bare Si nanopowders and Si/amorphous carbon composite microspheres (denoted as Si/AC) with filled structures. The synergistic effects of structural merits owing to the spherical morphology with empty nanovoids for liquid electrolyte penetration and a graphitic carbon layer with high electrical conductivity result in the superior lithium-ion storage performances of Si/AC@GC microsphere. The composite-based electrode delivers a high reversible capacity of 803 mA h g−1 after 200 cycles at 1.0 A g−1, indicating long-term cycling stability. Even at 5.0 A g−1, the electrode exhibits stable reversible discharge capacity of 589 mA h g−1 without significant capacity loss.

Rational Design of Perforated Bimetallic (Ni, Mo) Sulfides/N‐doped Graphitic Carbon Composite Microspheres as Anode Materials for Superior Na‐Ion Batteries (Small Methods 9/2021)

Front Cover In article number 2100195, Kim, Cho, and co-workers prepared highly conductive 3-DOM microspheres comprising bimetallic Ni7S6-MoS2 crystals and N-doped graphitic carbon by spray pyrolysis. 40-nm-sized mesopores with open channels and N-doped graphitic carbon were incorporated into the composite microsphere. Combined with a rational architecture, synthesized mesoporous composite microspheres exhibited superior electrochemical properties as an anode material for Na ion batteries.

Rational Design of Perforated Bimetallic (Ni, Mo) Sulfides/N-doped Graphitic Carbon Composite Microspheres as Anode Materials for Superior Na-Ion Batteries.

Highly conductive 3D ordered mesoporous Ni7 S6 -MoS2 /N-doped graphitic carbon (NGC) composite (P-NiMoS/C) microspheres are prepared as anode materials for Na-ion batteries. The rationally designed nanostructure comprises stable Ni7 S6 - and MoS2 -phases along with the homogeneously distributed ordered mesopores (ϕ=50nm) over the external and internal structures generated through thermal decomposition of polystyrene nanobeads (ϕ=100nm). Therefore, the P-NiMoS/C microspheres deliver initial discharge capacities of 662, 419, 373, 300, 231, 181, and 146mAhg-1 at current densities of 0.5, 1, 2, 4, 6, 8, and 10Ag-1 , respectively. Furthermore, P-NiMoS/C exhibits a stable discharge capacity of 444mAhg-1 at the end of the 150th cycle at a current density of 0.5Ag-1 , indicating higher cycling stability than the filled, that is, non-mesoporous, Ni3 S2 -MoS2 /NGC (F-NiMoS/C) microspheres and filled carbon-free Ni3 S2 -MoS2 (F-NiMoS) microspheres. The superior electrochemical performance of P-NiMoS/C microspheres is attributed to the rapid Na+ ion diffusion, alleviation of severe volume stress during prolonged cycling, and higher electrical conductivity of NGC, which results in fast charge transfer during the redox processes. The results in the present study can provide fundamental knowledge for the development of multicomponent, porous, and highly conductive anodes for various applications.

Synthesis of yolk‐shell‐structured iron monosulfide‐carbon microspheres and understanding of their conversion reaction for potassium‐ion storage

Nanostructured transition metal chalcogenides (TMCs) have attracted attention as potential anode materials owing to the anticipation of next-generation battery systems, particularly potassium-ion batteries (PIBs). In this study, the electrochemical reaction mechanism of iron monosulfide (FeS) with potassium ions was systemically investigated for the first time. To enhance the electrochemical properties by improving the structural stability and electrical conductivity during cycling, rational strategies of introducing a yolk-shell architecture via an aerosol process and pitch solution infiltration were applied, resulting in the formation of yolk-shell-structured FeS/pitch-derived carbon composite microspheres (Y-FeS@C). From in situ and ex situ investigations of electrodes in fully discharged and charged states, the following reaction mechanism was determined from the second cycle onward: 4Fe + 4K2S ↔ KxFe2S3 + FeS + Fe + (8 − x)K+ + (8 − x)e−. The inhibition of substantial FeS crystal growth thanks to the pitch-derived carbon encapsulation as well as the formation of metallic Fe after the initial conversion reaction contributed to the excellent electrochemical kinetic properties of Y-FeS@C. Y-FeS@C showed stable cycle performance (256.5 mA h g−1 for the 100th cycle at 0.5 A g−1) and high rate capability (113.8 mA h g−1 at 5.0 A g−1) as an anode material for PIBs.

Vertical graphene growth on uniformly dispersed sub-nanoscale SiOx/N-doped carbon composite microspheres with a 3D conductive network and an ultra-low volume deformation for fast and stable lithium-ion storage

Vertical graphene growth on subnanoscopically and homogeneously dispersed SiOx and carbon composite microspheres shows fast and stable lithium ion storage behavior.

ZnO nanoconfined 3D porous carbon composite microspheres to stabilize lithium nucleation/growth for high-performance lithium metal anodes

The lithiophilic nucleation seed is confined by the carbon layer to improve the cycling performance of the lithium metal anode.

A Salt-Templated Strategy toward Hollow Iron Selenides-Graphitic Carbon Composite Microspheres with Interconnected Multicavities as High-Performance Anode Materials for Sodium-Ion Batteries.

In this work, a facile salt-templated approach is developed for the preparation of hollow FeSe2 /graphitic carbon composite microspheres as sodium-ion battery anodes; these are composed of interconnected multicavities and an enclosed surface in-plane embedded with uniform hollow FeSe2 nanoparticles. As the precursor, Fe2 O3 /carbon microspheres containing NaCl nanocrystals are obtained using one-pot ultrasonic spray pyrolysis in which inexpensive NaCl and dextrin are used as a porogen and carbon source, respectively, enabling mass production of the composites. During post-treatment, Fe2 O3 nanoparticles in the composites transform into hollow FeSe2 nanospheres via the Kirkendall effect. These rational structures provide numerous conductive channels to facilitate ion/electron transport and enhance the capacitive contribution. Moreover, the synergistic effect between the hollow cavities within FeSe2 and the outstanding mechanical strength of the porous carbon matrix can effectively accommodate the large volume changes during cycling. Correspondingly, the composite microsphere exhibits high discharge capacity of 510 mA h g-1 after 200 cycles at 0.2 A g-1 with capacity retention of 88% when calculated from the second cycle. Even at a high current density of 5.0 A g-1 , a high discharge capacity of 417 mA h g-1 can be achieved.

Nickel vanadate microspheres with numerous nanocavities synthesized by spray drying process as an anode material for Li-ion batteries

For use in next-generation energy storage applications, including electric vehicles, capacity and cycle life of lithium ion batteries need further improvement. Moreover, to achieve fast lithiation kinetics of the electrode materials, high power density and quick charging ability are necessary. Nickel vanadate (Ni3V2O8) microsphere with tens of nanocavities is one of candidates for anode materials suitable for lithium ion batteries. The synthesis of microspheres is possible by a pilot-scale spray drying process and facile one-step oxidation heat treatment. Dextrin, which is present in the microspheres after spray drying process, plays a key role in the formation of nanocavities. Oxidation at different temperatures yields carbon composite microspheres with nanocavities and hierarchical Ni3V2O8 microspheres with nanocavities. The nanocavities facilitate electrolyte contact with the electrode material and alleviate volume change during lithiation/delithiation. The merits of the nanocavities in the Ni3V2O8 microspheres enable a high discharge capacity of 1045 mA h g−1 for the 2nd cycle at 1 A g−1 and long cycle life. Furthermore, Ni3V2O8 microspheres deliver a high discharge capacity of 612 mA h g−1 at a high current density of 6 A g−1.

Hierarchical MoS2 /Carbon Composite Microspheres as Advanced Anodes for Lithium/Sodium-Ion Batteries.

It is crucial to design advanced electrodes with large Li/Na-ion storage capacities for the development of next-generation battery systems. Herein, hierarchical MoS2 /C composite microspheres were constructed by facile template-free self-assembly sulfurization plus post-carbonization. Cross-linked MoS2 nanosheets and outer carbon layer are organically combined together to form composite microspheres with diameters of 400-500 nm. Due to enhanced electrical conductivity and good structural stability, the MoS2 /C composite microspheres exhibit substantially improved Li/Na-ion storage performance. Compared to unmodified MoS2 , MoS2 /C composite microspheres deliver higher Li/Na-ion storage capacity (Li+ : 1017 mA h g-1 at 100 mA g-1 and Na+ : 531 mA h g-1 at 100 mA g-1 ), as well as better rate capability (Li+ : 434 mA h g-1 at 1 Ag-1 and Na+ : 102 mA h g-1 at 1 Ag-1 ) and capacity retention (Li+ : 902 mA h g-1 after 200 cycles and Na+ : 342 mA h g-1 over 100 cycles). The superior Li/Na-ion storage performance is mainly attributed to the unique porous microsphere architecture with increased electrode/electrolyte interfaces and more diffusion paths for Li/Na ion insertion. Additionally, the carbon coating can not only improve the electronic conductivity, but also suppress the shuttle effect of polysulfides.

Superior electrochemical properties of micron-sized aggregates of (Co0.5Fe0.5)3O4 hollow nanospheres and graphitic carbon

Morphology-controlled micron-sized aggregates consisted of hollow nanospheres and graphitic carbon are considered to be efficient electrode materials for lithium-ion batteries because the advantages of hollow nanospheres are combined with those of micron-size powders with easy processability. In this study, carbon microspheres with extremely large surface area of 3350 m2 g−1 are successfully used as templates to synthesize (Co0.5Fe0.5)3O4-graphitic carbon (CoFeO-GC) composite microspheres, which in turn, are composed of hollow nanospheres. The CoFe alloy nanospheres act as catalyst in formation of graphitic carbon during reduction process and transform into metal oxide hollow nanospheres after oxidation by nanoscale Kirkendall diffusion. Owing to their unique structure, CoFeO-GC composite microspheres show lithium-ion storage performances superior to those of the CoFeO-amorphous carbon composites with ultrafine nanocrystals and dense structure. The CoFeO-GC composite microspheres have extremely high capacities of 1072 and 681 mA h g−1 at current densities of 1 and 3 A g−1, respectively, after 350 cycles. This hybrid structure employs synergistic effect of the hollow nanosphere aggregate and high content of graphitic carbon with high electrical conductivity, resulting in superior cycling and rate performances, when tested as anode materials for lithium-ion batteries.

Dual Carbon Layered Tin Oxide Anode for High Energy Lithium Ion Batteries

The development of high–capacity anode materials for lithium ion batteries (LIBs) is a key step toward achieving large–scale energy storage applications for portable electronic devices, electrical vehicles, and hybrid electrical vehicles.1 Since its first discovery, the current commercial LIBs have been using graphite as anode material. Although this carbon–based anode is cheap, abundant and reliable, however it provides a limited theoretical capacity of 372 mAh/g, hence hampering the establishment of high–energy density LIBs to meet huge technological demands in the near future.2 To replace the incumbent anode, intensive research has been devoted on the alloy–based materials such as silicon, germanium, tin, and tin oxide (SnO2). Among these candidates, SnO2 is a promising anode material attributing to its low cost, nontoxicity, low operating potential (0.25 V vs. Li/Li+), high theoretical capacity (782 and 1,493 mAh/g for alloying/de–alloying and both alloying/de–alloying and conversion reaction, respectively), and easy synthesis in regard to nanostructures.3 It was widely studied that employing the pristine SnO2 anode for LIBs may face a significant barrier because of a severe volume change during the electrochemical cycle, causing pulverization and cracks and eventually the loss of electrical conduction paths. In the meantime, the new–fresh cracks that are exposed to the electrolyte may form a continuous solid electrolyte interphase (SEI)–filming process resulting in a thickened SEI layer on the surface of SnO2 anode. Consequently, the cell cannot avoid a rapid capacity fading.4 To overcome these problems, we synthesized the rational anode material consisting of hierarchical structure and dual carbon layers. The hierarchical structures of SnO2 anode are aimed at increasing the active surface area, allowing more Li ions can be stored in the spaces, thus promoting a faster Li ion diffusivity. In addition, dual carbon layers are aimed at alleviating the volume change during charge-discharge reaction, leading to mechanically keep the structure of electrode stable and enhance the ionic conductivity at the interfaces. As the results, our C@SnO2@C anode demonstrated a significant electrochemical performance such as long cycle life and high reversible capacity, hence postulating a solution for commercialization of Sn-based anode for LIBs in the market. [References] Chen, Y. M.; Lu, Z. G.; Zhou, L. M.; Mai, Y. W.; Huang, H. T. Triple–coaxial electrospun amorphous carbon nanotubes with hollow graphitic carbon nanospheres for high– performance Li ion batteries. Energy Environ. Sci. 2012, 5, 7898–7902. Ko, Y. N.; Park, S. B.; Kang, Y. C. Design and fabrication of new nanostructured SnO2–carbon composite microspheres for fast and stable lithium storage performance. Small 2014, 10, 3240–3245. Thomas, R.; Rao, G. M. SnO2 nanowire anchored graphene nanosheet matrix for the superior performance of Li–ion thin film battery anode. J Mater Chem A 2015, 3, 274–280. Zhu, C. R.; Xia, X. H.; Liu, J. L.; Fan, Z. X.; Chao, D. L.; Zhang, H. et al. TiO2 nanotube@SnO2 nanoflake core–branch arrays for lithium–ion battery anode. Nano Energy 2014, 4, 105–112.

SiO2/Carbon Composite Microspheres with Hollow Core–Shell Structure as a High‐Stability Electrode for Lithium‐Ion Batteries

AbstractThe SiO2/carbon composite material used as a lithium‐ion battery (LIB) anode was synthesized by aerosol spraying a mixture of polyvinyl alcohol (PVA) solution and SiO2 nanoparticles, followed by coating polyacrylonitrile (PAN) on the SiO2/PVA surface and an annealing treatment at 800 °C. The as‐prepared SiO2/po‐C@C has a hollow core–shell structure. The hollow section contributes to accommodate the volume expansion of SiO2 nanoparticles; the skeleton of porous carbon in the core not only enhances the electronic conductivity, but also provides the lithium‐ion diffusion path; the PAN‐based carbon shell benefits for forming a stable solid electrolyte interphase (SEI) film. This core–shell structure could partly alleviate the pulverization of the SiO2/po‐C@C particles and also perform excellent electrochemical performances. Compared with the SiO2@C composite, the SiO2/po‐C@C composite possesses a high specific charge capacity of 669.8 mA h g−1 at a current density of 100 mA g−1 after 100 charge and discharge cycles with a high capacity retention of 98.6 %. Therefore, the SiO2/po‐C@C composite with a hollow core‐shell structure shows great potential as an anode material for future LIBs.

Microwave Irradiation Assisted Preparation of Chitosan Composite Microsphere for Dye Adsorption

Chitosan-activated carbon composite microspheres were prepared by emulsion cross-linking method and its adsorption properties for methyl orange were studied. Chitosan solution was mixed with activated carbon powder and then chitosan was cross-linked by epichlorohydrin under microwave irradiation. SEM photos show that the composite microspheres have diameters of 200–400 μm and activated carbon powder dispersed on the surface of composite microsphere. FTIR spectrum indicates chitosan is successfully cross-linked. Microwave irradiation can effectively shorten the cross-linking time. Composite microspheres have enhanced dye adsorption capacity for methyl orange compared to chitosan microspheres. Kinetic studies showed that the adsorption followed a pseudo-second-order model. Isotherm studies show that the isotherm adsorption equilibrium is better described by Freundlich isotherm. Regeneration results show that adsorption capacity of composite microsphere decreased about 5.51% after being reused for three times. These results indicated that chitosan-activated carbon composite microsphere has potential application in the removal of dye from wastewaters.

Double-Sided Carbon Covered Hierarchical Tin Oxide Anode for High Capacity Lithium-Ion Batteries

The development of high–capacity anode materials for lithium ion batteries (LIBs) is a key step toward achieving large–scale energy storage applications for portable electronic devices, electrical vehicles, and hybrid electrical vehicles.1 Since its first discovery, the current commercial LIBs have been using graphite as anode material. Although this carbon–based anode is cheap, abundant and reliable, however it provides a limited theoretical capacity of 372 mAh/g, hence hampering the establishment of high–energy density LIBs to meet huge technological demands in the near future.2 To replace the incumbent anode, intensive research has been devoted on the alloy–based materials such as silicon, germanium, tin, and tin oxide (SnO2). Among these candidates, SnO2 is a promising anode material attributing to its low cost, nontoxicity, low operating potential (0.25 V vs. Li/Li+), high theoretical capacity (782 and 1493 mAh/g for alloying/de–alloying and both alloying/de–alloying and conversion reaction, respectively), and easy synthesis in regard to nanostructures.3 It was widely studied that employing the pristine SnO2 anode for LIBs may face a significant barrier because of a severe volume change during the electrochemical cycle, causing pulverization and cracks and eventually the loss of electrical conduction paths. In the meantime, the new–fresh cracks that are exposed to the electrolyte may form a continuous solid electrolyte interphase (SEI)–filming process resulting in a thickened SEI layer on the surface of SnO2 anode. Consequently, the cell cannot avoid a rapid capacity fading.4 To overcome these problems, we synthesized the rational anode material consisting of hierarchical structure and thin double carbon layers. The hierarchical structures of SnO2 anode are aimed at increasing the active surface area, allowing more Li ions can be stored in the spaces, thus promoting a faster Li ion diffusivity. In addition, thin double carbon layers are aimed at alleviating the volume change during charge-discharge reaction, leading to mechanically keep the structure of electrode stable and enhance the ionic conductivity at the interfaces. As the results, our C@SnO2@C anode demonstrated a significant electrochemical performance such as long cycle life and high reversible capacity, hence postulating a solution for commercialization of Sn-based anode for LIBs in the market. [References] Chen, Y. M.; Lu, Z. G.; Zhou, L. M.; Mai, Y. W.; Huang, H. T. Triple–coaxial electrospun amorphous carbon nanotubes with hollow graphitic carbon nanospheres for high– performance Li ion batteries. Energy Environ. Sci. 2012, 5, 7898–7902. Ko, Y. N.; Park, S. B.; Kang, Y. C. Design and fabrication of new nanostructured SnO2–carbon composite microspheres for fast and stable lithium storage performance. Small 2014, 10, 3240–3245. Thomas, R.; Rao, G. M. SnO2 nanowire anchored graphene nanosheet matrix for the superior performance of Li–ion thin film battery anode. J Mater Chem A 2015, 3, 274–280. Zhu, C. R.; Xia, X. H.; Liu, J. L.; Fan, Z. X.; Chao, D. L.; Zhang, H. et al. TiO2 nanotube@SnO2 nanoflake core–branch arrays for lithium–ion battery anode. Nano Energy 2014, 4, 105–112.

Sustainable Preparation of Copper Particles Decorated Carbon Microspheres and Studies on Their Bactericidal Activity and Catalytic Properties

Cu particles decorated carbon composite microspheres (CCMs) with a unique sesame ball structure have been prepared by combining the mass-producible spray drying technique with calcinations. The conventional cuprammonium cellulose complex solution obtained by dissolving cellulose in a cuprammonia solution has been applied as raw materials for the preparation of Cu(NH3)42+/cellulose complex microspheres via a spray drying process. The resulted Cu(NH3)42+/cellulose complex microspheres are then transformed into the Cu particles homogeneously decorated porous carbon spheres in situ by calcinations at 450 or 550 °C. The coordination effect between the Cu(NH3)42+ species and the hydroxyl groups of the cellulose macromolecules has been exploited for directing the dispersion of the Cu particles in the resultant composite CCMs. The antimicrobial effects of the CCMs are evaluated by determining the minimum growth inhibitory concentrations using Staphylococcus aureus and Escherichia coli as representatives, respecti...