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Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are the most typical pathogenic bacteria with a significantly high risk of bio-contamination, widely existing in hospital and public places. Recent studies on antibacterial materials and the related mechanisms have attracted more interests of researchers. However, the antibacterial behavior of materials is usually evaluated separately on the single bacterial strain, which is far from the practical condition. Actually, the interaction between the polymicrobial communities can promote the growing profile of bacteria, which may weaken the antibacterial effect of materials. In this work, a 420 copper-bearing martensitic stainless steel (420CuSS) was studied with respect to its antibacterial activity and the underlying mechanism in a co-culturing infection model using both E. coli and S. aureus. Observed via plating and counting colony forming units (CFU), Cu releasing, and material characterization, 420CuSS was proved to present excellent antibacterial performance against the mixed bacteria with an approximately 99.4 % of antibacterial rate. In addition, 420CuSS could effectively inhibit the biofilm formation on its surfaces, resulting from a synergistic antibacterial effect of Cu ions, Fe ions, reactive oxygen species (ROS), and proton consumption of bacteria.

In this paper, we report the microstructure and hydrogen storage properties of TiFe-based alloys containing chromium (Cr), manganese (Mn) and yttrium (Y). Four alloy samples with chemical composition of TiFe0.9Cr0.1, TiFe0.9Cr0.1Y0.05, TiFe0.9Mn0.1 and TiFe0.9Mn0.1Y0.05 were prepared by arc melting, and the effects of alloying elements Cr, Mn and Y on microstructure and hydrogenation kinetics and thermodynamics were investigated in detail. It was found that all the four alloys have the main phase of TiFe intermetallic compound. A small amount of secondary phase can be also detected in the alloy samples. Cr substituted alloys have larger lattice parameters than that of Mn substituted alloys. Y in the alloys is mainly existed in the form of α-Y phase, and it transform into YH3 during hydrogenation process. Very sloped equilibrium plateau regions are observed in Cr substituted alloys, while the Mn substituted alloys have flat equilibrium plateaus. Y addition has almost no influence on pressure–composition–isotherm (p–c–T) curves of Cr substituted alloy, but slightly decrease the equilibrium plateaus of Mn substituted alloys. Hydrogen absorption and desorption kinetics strongly depend on the equilibrium plateau pressures. As a result, the Cr substituted alloys with lower equilibrium plateau pressure have faster hydrogen absorption and slower desorption kinetics compared with Mn substituted alloys. The Cr substituted alloys have poor powdering resistance compared with Mn substituted alloys during hydrogenation cycles, which can be ascribed to the higher hardness of alloy matrix caused by Cr substitution.

In recent years, continuous and stable antibacterial ability has received extensive attention in the field of antibacterial composite materials. The researchers expect a kind of antibacterial composites with continuous and stable antibacterial acting and good biocompatibility. Herein we used a unique in-situ modification methods which inspired self-polymerization of dopamine to fix the nano-Ag on the bacterial cellulose (BC). The antibacterial properties of composites were tested in two new methods (antibacterial stability and antibacterial durability). We researched the cause of the antibacterial properties by analyzing the valence state and binding energy of Ag. The chelation between PDA and Ag is considered to the key to stable release of Ag+. The three-dimensional network of BC is also thought to play some role in making Ag+ release stability. Moreover, PDA as a reducing agent, reacting with Tollens reagent to produce nano-Ag nanoparticles, is a good method for reducing the toxicity of nano-Ag and enhancing the biological compatibility of composites. Our results hence illustrate that the BC antimicrobial composites by PDA in-situ reduction nano-Ag has a great potential as an antibacterial dressing with stable antimicrobial properties and biocompatibility.

Titanium (Ti) is the widely used implant material in clinic, however, failures still frequently occur due to its bioinertness and poor antibacterial property. To improve the biological and antibacterial properties of Ti implants, micro-nanostructured hydroxyapatite (HA) coating was prepared on Ti surface by micro-arc oxidation (MAO), and then the antibacterial agent of chitosan (CS) was loaded on the HA surface through dip-coating method. The results showed that the obtained HA/CS composite coating accelerated the formation of apatite layer in SBF solution, enhanced cell adhesion, spreading and proliferation, and it also inhibited the bacterial growth, showing improved biological and antibacterial properties. Although, with the increased CS amount, the coverage of HA coating would be enlarged, resulting in depressed biological property, however, the antibacterial property of the composite coating was enhanced, and the cytotoxicity about CS was not detected in this work. In conclusion, the HA/CS coating has promising application in orthopedics, dentistry and other biomedical devices.

Injectable therapeutics enabled by engineered biomaterials are becoming increasingly popular, transforming traditional clinical practice to become a minimally invasive and regenerative regime. Compared to preformed biomaterials, injectable biomaterials allow for more precise implantation into deeply enclosed anatomical locations and for the repair of irregularly shaped lesions, demonstrating great translational potential. Continuously emerging clinical needs and advances in materials science have driven an evolution in injectable biomaterials from structural fillers to multifunctional platforms. Integrating disparate functions to design injectable biomaterials for clinical translation remains a considerable challenge, as does the selection of the appropriate design considerations for specific applications. This article aims to review the design and fabrication considerations of injectable biomaterials in the context of medical translation, the engineering strategies used for new materials to meet the growing demands in regenerative and intelligent medicine, and the progress in their development for selected clinical applications. Specifically, three exemplary areas, injectable bone cements, hydrogels, and electronics, all of which demonstrate significant promise in terms of translation and commercialization, are reviewed in detail. In addition, their translational status and future challenges are discussed. It is also envisioned that the mutual collaboration between researchers, clinicians, entrepreneurs, engineers, and patients will inspire and catalyze the innovation and translation of injectable biomaterials.

Cu(OH)2 nanowire arrays supported on nanoporous copper were synthesized via anodic oxidation at different voltages. Nanoporous copper was prepared through dealloying Zr50Cu50 amorphous ribbon to obtain a uniform aperture. This unique composite structure combines the excellent conductivity of nanoporous copper with the high catalytic activity of Cu(OH)2 nanowires and can be directly used as a support electrode to explore the electrocatalytic oxidation of glucose. The sensor showed a wide linear response range from 10.0 μM to 10.0 mM and high sensitivity of 1.866 mA cm−2 M−1. As such, it provides a basis for the future production of enzyme-free glucose sensors.

A novel carbon nanotubes (CNTs)-reinforced magnesium (Mg) matrix composite was successfully fabricated via an in situ synthesis of Mg on the surfaces of CNTs and a powder metallurgy (PM) process. The nanoscale Mg grains were first synthesized in situ on CNTs via the solid-state displacement reaction of lithium (Li) to Mg in anhydrous magnesium chloride (MgCl2) to obtain Mg-encapsulated CNTs (CNTs@Mg) composite powders. These were used to fabricate CNTs@Mg bulk composites via the PM method. In the CNTs@Mg in situ composite structure, the synthesized Mg grains were in contact with CNTs in a stacking manner, and nanoscale contact and diffusion bonding occurred at the CNTs–Mg interface, realizing not only strong interface bonding between CNTs and Mg but also the dispersion of CNTs in the Mg matrix. The CNTs@Mg composites exhibited improved mechanical properties. The microhardness, ultimate tensile strength (UTS), and breaking elongation of 4.0 wt% CNTs@Mg bulk composite were increased by approximately 43.5%, 33.4%, and 31.3% compared with pure Mg bulk, respectively. Furthermore, the mechanical properties of the CNTs@Mg bulk composites were superior to those of CNT/Mg composites fabricated via the traditional addition process. Therefore, the investigated CNTs@Mg composites are promising candidates for the field of lightweight structural materials.

A novel magnetic targeted drug delivery carrier based on a carbon nanotube (Fe)/hydroxyapatite (CNT(Fe)/HA) composite was successfully fabricated by an in situ synthesis of CNTs in HA nanopowder using Fe catalysts and subsequent chemical modification of the as-fabricated CNT(Fe)/HA by chitosan (CS) and folic acid (FA) for a controllable release of an anticancer drug doxorubicin (DOX). The synthesized CNTs, Fe, and HA self-assembled into a composite structure in situ during the synthesis. After the acid treatment, the CNTs were shorter and homogeneously dispersed, the tips of the CNTs were opened, and oxygen-containing functional groups were introduced onto the CNTs. Upon the functional modification through the surface coating with CS and FA, the functionalized CNT(Fe)/HA became capable of loading DOX through both π–π stacking and electrostatic adsorption of FA. The results showed that the average drug-loading rate of DOX was 130 wt%. Furthermore, the pH response of FA-CS-CNT(Fe)/HA enabled the release of a large amount of DOX in phosphate-buffered saline (PBS) at pH = 5.5 with an average drug release rate of 52 wt% after 72 h. In contrast, the drug release in PBS at pH = 7.4 was only 8 wt%. In addition, the saturation magnetization, coercive force, and remanence to saturation magnetization ratio of DOX-FA-CS-CNT(Fe)/HA were 0.88 emu g−1, 668.96 Oe, and 0.44, respectively, indicating its potential for drug transport under strong external magnetic fields, which could enable magnetic targeted delivery.

Ternary Mg86Y10Ni4 alloy was successfully prepared by vacuum induction melting and subsequent melt-spinning technique. The phase composition and microstructure of the melt-spun and hydrogenated samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy measurements. The melt-spun alloy had an amorphous structure, and it transformed into nanocrystalline during the first hydrogenation process. The hydrogenated sample was composed of MgH2, Mg2NiH4, YH2, and a small amount of YH3. The hydrogen absorption/desorption kinetics and thermodynamics were measured by Sievert's apparatus at various temperatures. It was found that the melt-spun Mg86Y10Ni4 alloy could be fully activated after five hydrogenation and dehydrogenation cycles at 380 °C, and it exhibited a reversible gravimetric hydrogen storage capacity of about 5.3 wt%. The enhanced hydrogen sorption kinetics during the first few cycles can be attributed to the increased specific surface caused by the pulverization and cracking of the alloy particles. The activation energy for dehydrogenation reaction was determined to be 67 kJ/mol and 71 kJ/mol by using Arrhenius equation and Kissinger equation respectively. The thermodynamics of the sample was also evaluated by pressure–composition–isotherms, and the results shown that the enthalpy and entropy changes of Mg/MgH2 transformation in the Mg86Y10Ni4 alloy were slightly higher than that of pure Mg/MgH2.

The influences of rare earth element yttrium (Y) on microstructure, mechanical properties and fracture characteristics of Ti-25Zr-xY (x = 0, 0.5, 1, 2, 3, 4, 5, at%) alloy were investigated. Compositional and microstructural characterization of the as-cast material was conducted by XRD, SEM and TEM. XRD analysis showed that no other phase was found in the specimens, which completely consisted of α and α-Y phases. Addition of trace amounts of Y to the Ti-25Zr alloys induced significant changes in the microstructure, including the decrease in sizes of prior β grain boundaries and α platelets size. The constitutional supercooling were responsible for the grain refinement. Owing to the low solubility and segregation of Y element in the Ti-Zr alloy, when the Y content was less than 1 (at%), the fine and uniformly distributed α-Y phases were dispersed within the grains. The refinement of grains and α-lath and dispersion of α-Y within the grains contributed to the desirable compression performance. By contrast, when the content of Y exceeded 1 at%, the grain boundary segregation of Y was more distinct. Consequently, the mechanical properties deteriorated remarkably because of the serious segregation of the brittle α-Y phase at grain boundaries.

A three-dimensionally (3D) ordered macro/mesoporous carbon (3DOMC) is synthesized by one-step template method as a TiO2 supporter, and this TiO2/3DOMC hybrid plays the role of immobilizers and can limit any polysulfides from escaping the cathode. The TiO2/3DOMC exhibits high pore volume and specific surface area, accommodating up to 73.2 wt% in sulfur content. As a sulfur host, S/TiO2/3DOMC composite was able to delivered 1105 mAh g−1 on first discharge and 695 mAh g−1 after 150 cycles at a current rate of 0.5 C. Even though at 2 C this material was able to keep a capacity of 551 mAh g−1. We attribute the superior performance to the good conductivity and structural restriction of carbon and the intense electrostatic attraction between metal-oxygen bond and polysulfides to encapsulate sulfur of the TiO2/3DOMC.

Although Ti is widely used in orthopedic implants, its bio-inert characteristics and poor antibacterial activity may result in implant failure. To counter this problem, in this study, we loaded simvastatin, a bioactive compound that promotes osteogenesis, in TiO2 nanotubes and a thermosensitive chitosan-glycerin-hydroxypropyl methyl cellulose hydrogel (CGHH) was then layered on top of these nanotubes. At normal human-body temperature (37 °C), CGHH was present in a sol state, thus facilitating the controlled release of simvastatin to enhance differentiation in MC3T3-E1 osteoblasts. In vitro cell-culture studies suggested that CGHH in a gel state would induce macrophage polarization to the pro-inflammatory M1 phenotype. In vitro testing against Escherichia coli and Staphylococcus aureus indicated no antibacterial activity in CGHH in both sol and gel states. However, the results of subcutaneous infection animal models suggested that CGHH showed excellent in vivo antibacterial activity, which can be explained by the fact at high temperatures induced by an infection, CGHH transitioned into a gel state and released large amounts of glycerin. Such a high glycerin dosage induced an acute inflammatory reaction and antibacterial activity. Thus, due to their enhanced osteogenesis capacity at normal body temperature and antibacterial characteristics in the presence of infection, the newly designed simvastatin-loaded CGHH-encapsulated TiO2 nanotubes are promising materials for application in orthopedic implants.

Near-infrared (NIR)-light responsive graphene have been shown exciting effect on cancer photothermal ablation therapy. Herein, we report on the preparation of Fe3O4-decorated hollow graphene microspheres (rGO@Fe3O4) by a facile spray drying and coprecipitation method for the magnetically targeted and NIR-responsive chemo-photothermal combination therapy. The microspheres displayed very high specific surface area (~ 120.7 m2 g−1) and large pore volume (~ 1.012 cm3 g−1), demonstrating distinct advantages for a high loading capacity of DOX (~ 18.43%). NIR triggered photothermal effect of the rGO@Fe3O4 microspheres responded in an on-off manner and induced a high photothermal conversion efficiency. Moreover, The Fe3O4 on the microspheres exhibited an excellent tumor cells targeting ability. The chemo-photothermal treatment based on rGO@Fe3O4/DOX showed superior cytotoxicity towards Hela cells in vitro. Our studies indicated that rGO@Fe3O4/DOX microcapsules have great potential in combined chemo-photothermal cancer treatment.

The porous TiO2 coatings containing Ca/P/Ag were separately prepared on titanium (Ti) surface by one-step (micro-arc oxidation) and two-step methods (micro-arc oxidation and cathodic deposition), and then their surface morphology, composition, biological and antibacterial properties were compared. The results showed that the porous coatings containing Ca/P/Ag achieved by different methods showed similar surface morphology and elemental composition, however, by one-step method, silver existed in the coating as silver phosphate, while in the coatings prepared by two-step method, silver existed as metallic silver. Although both coatings showed excellent antibacterial property (the antimicrobial rate is over 99.9%), the surface coating prepared by one-step method had a more suitable release curve of Ag. In addition, the surface coating prepared by one-step method also presented better biological property, which was due to its enhanced surface roughness and hydrophilicity. Combining with its easy operation and long-term antibacterial property, its prospect for clinical application is more promising.

Objective: To construct a porous titanium-based implant with good biocompatibility and appropriate modulus matching human bone. Methods: Porous titanium with triangular, quadrangular and hexagonal prism as structure monomer were constructed by 3D printing, and the effects of pore structures on the mechanical and biological properties of materials were investigated by computational simulation, mechanical property tests and cell adhesion and proliferation tests. Results: The modulus of titanium with quadrangular monomer was the closest to that of human bone. Besides, the quadrangular sample also shows the best cytocompatibility, presenting the most promotion effects on cell proliferation. Conclusion: The porous titanium constructed by quadrangular monomer has the best comprehensive performance, and the relevant results can provide data support for the design and clinical application of 3D printing porous titanium-based implants.

In this study, porous TiO2/HA coating and petaling structured TiO2/HA coatings were prepared by micro-arc oxidation (MAO) on titanium (Ti) surface to enhance biocompatibility. Morphology, phase composition, roughness and hydrophilicity were separately investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscope (AFM), and contact angle meter. The biocompatibility was evaluated by in vitro cell co-culture experiment. The results revealed that, the surface roughness and hydrophilicity of petaling structured TiO2/HA coatings were much larger than that of the porous structured TiO2/HA. And with the increased density of the HA petals, the roughness and hydrophilicity increased. MC3T3-E1 cell adhesion, spreading, proliferation and ALP expression were most enhanced on TiO2/HA coatings with the maximum density of HA petals. The beneficial effect of structures on biocompatibility may be due to the improved surface roughness and hydrophilicity.

Dissimilar joining of magnesium and aluminum using a compound casting process was investigated in the present work. For the first time, a Ni interlayer prepared by plasma spraying was inserted between the two base metals to improve the interfacial characteristics. Examination of the interfacial regions using scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, and X-ray diffraction revealed the formation of a three-layered interface between Mg and Al without the interlayer. The thickness of the interface was approximately 600 μm when the casting was performed at 700 °C and increased with increasing casting temperature. However, with the addition of the Ni interlayer, the Al-Mg reaction was successfully prevented, and metallurgical bonding between the Ni interlayer and two base metals was achieved at a casting temperature of 700 °C. Upon increasing this temperature, Mg-Ni and Al-Ni intermetallics were generated at the separate interfaces. The shear strength of the Mg/Al bimetallic castings with the Ni interlayer was substantially improved compared with that of the direct Mg/Al joint, with a maximum value of 25.4 MPa achieved at 700 °C. Fracture occurred mainly along the Mg/Ni interface for the Mg/Ni/Al multilayer structure castings.

In this paper, the titanium (Ti) surfaces with different structure, composition, crystal form and grain size are prepared by micro arc oxidation and thermal treatment, and then their hydrophilicity and surface roughness are investigated. The experimental results show that there is no necessary relationship between hydrophilicity and surface roughness. For hydroxyapatite (HA) coatings with different surface structures, the structure with more HA amount has better hydrophilicity. And, with the same porous structure, HA surface endows better hydrophilicity than TiO2. Anatase surface with small grain size has better hydrophilicity and rutile has better hydrophilicity than anatase. Combined with their biological properties which have been well reported, the dependent relationship of hydrophilicity and biological properties can be concluded, namely the good biological properties can be obtained by improving the hydrophilicity. This research work sheds light on the methods for optimization of biological properties of the implant materials.

A novel carbon nanotube (CNT)-alumina (Al2O3) synergistically reinforced magnesium matrix composite was successfully fabricated by the in situ synthesis of vertically dispersive CNTs self-organized on Al2O3 microspheres using catalytic chemical vapor deposition (CCVD) and powder metallurgy (PM) methods. Using the CCVD method, the in situ synthesized CNT-Al2O3 synergistic reinforcements presented an urchin-like and spherically symmetrical structure, and were prone to staggered arrangement with each other. Using the PM process, the CNT-Al2O3 reinforcements were homogeneously distributed and formed close-knit interfacial bonds with the Mg matrix. Combining the strengthening effects of CNTs and Al2O3 microspheres, the mechanical properties of the CNT-Al2O3/Mg composite were improved apparently. The ultimate tensile strength and elongation to failure of the CNT-Al2O3/Mg composite increased by approximately 26.8% and 20.9% compared to those of pure Mg bulk, respectively, and its hardness was 38.9% higher than that of pure Mg. Furthermore, the mechanical properties of the CNT-Al2O3/Mg composite were significantly higher than those of Al2O3/Mg and CNT/Mg composites, indicating its excellent synergistically reinforcing effects. Therefore, the obtained CNT-Al2O3/Mg composite is expected to be a promising material for application in the field of lightweight structural materials.

Yttrium (Y) is selected to modify the microstructure of magnesium (Mg) to improve the hydrogen storage performance. Thereby, binary alloys with the nominal compositions of Mg24Yx (x = 1–5) are fabricated by inexpensive casting technique. Their microstructure and phase transformation during hydriding and dehydriding process are characterized by using X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy analysis. The isothermal hydrogen absorption and desorption kinetics are also measured by a Sievert's-type apparatus at various temperatures. Typical multiphase structures of binary alloy can be clearly observed. All of these alloys can reversibly absorb and desorb large amount of hydrogen at proper temperatures. The addition of Y markedly promotes the hydrogen absorption kinetics. However, it results in a reduction of reversible hydrogen storage capacity. A maximum value of dehydrogenation rate is observed with the increase of Y content. The Mg24Y3 alloy has the optimal desorption kinetic performance, and it can desorb about 5.4 wt% of hydrogen at 380 °C within 12 min. Combining Johnson–Mehl–Avrami kinetic model and Arrhenius equation, the dehydrogenation activation energy of the alloys are evaluated. The Mg24Y3 alloy also has the lowest dehydrogenation activation energy (119 kJ mol−1).

Aluminum (Al)-based amorphous alloys (hereinafter abbreviated as AAA) with good mechanical and anti-corrosion properties are ideal fillers for modified organic coatings. A novel polyurethane (PU)/Al/AAA composite coating was prepared by adding Al-based alloy powders, which were composed of Al and AAA powders. The effects of Al or AAA powder concentration on the mechanical behavior, corrosion resistance and infrared (IR) emissivity of PU/Al/AAA coatings were systematically investigated and compared with those of PU/Al coatings. The AAA particles surrounded by Al flakes form annular structures in the polymer matrix. With the increase of AAA powder concentration, the hardness, IR emissivity, wear resistance and anti-corrosion of the PU/Al/AAA coating are increased, whereas the adhesion strength is slightly decreased. Moreover, excess AAA powder has a negative effect on wear and corrosion resistance of the coating. The optimal AAA powder proportion in the filler was found to be 57 wt%, resulting in a composite coating with good mechanical and anti-corrosion properties as well as low IR emissivity. The AAA powder developed by this work can serve as a good modified filler for high-performance PU coatings.

The osteogenic activity of medical metal can be improved by lowering its surface stiffness and elastic modulus. However, it is very difficult to directly reduce the elastic modulus of medical metal surfaces. In this paper, with selected parameters, the titanium surface was treated via femtosecond laser irradiation. Micro indentation revealed that the femtosecond laser ablation can effectively reduce the surface Young's modulus and Vickers hardness of titanium. Besides, In order to explain the mechanical properties of degradation of titanium surface, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) was used to simulate the process of laser ablation process of titanium surface, and it was found that after the ablation of titanium surface, voids were produced in the subsurface layer. The simulation showed that the voids are formed by the cavitation of metastable liquid induced by high tensile stress and high temperature during femtosecond laser irradiation. Subsurface voids with a thickness of about 40 nm were observed under the oxide layer in the experiment. Cell experiments showed that the surface with low Young's modulus was more conducive to cell proliferation and osteogenic differentiation.

Orthopedic implant is commonly associated with occurrence or relapse of osteomyelitis. This study developed a hydrofluoric acid (HF) cleaned silicon nitride (Si3N4) implant Si3N4_AC for osteomyelitis control and established a rat tibial osteomyelitis model to evaluate its efficacy on eradicating periprosthetic infection and enhancing bone regeneration. In vitro studies revealed Si3N4_AC had improved biocompatibility and inhibited Staphylococcus aureus adhesion. A custom-made Si3N4_AC implant was prepared and inserted into the rat tibia longitudinal cavity inoculated with Staphylococcus aureus. The in vivo bacteriostatic and osteogenic efficacies of Si3N4_AC implant were evaluated by histological, microbiological and Micro-CT analyses and compared with implants of pure Ti and Si3N4 . Si3N4_AC implant group revealed 99.5% inhibition of periprosthetic Staphylococcus aureus compared to the osteomyelitis group after 14 days post-operation. Implant-adhering bacteria density of Si3N4_AC was also much lower than pure Ti and Si3N4. In addition, micro-CT evaluation of peri-implant bone formation under the condition of periprosthetic osteomyelitis after 30 days post-surgery confirmed the osteogenic ability of Si3N4_AC. Taken together, Si3N4_AC can be an effective orthopedic biomaterial to eradicate periprosthetic infection and enhance bone regeneration.

FeMn alloy is a promising biodegradable metal due to its high strength and biocompatibility, but the inadequate degradation rate and poor surface performance impede its further development. To overcome the drawbacks, femtosecond laser surface modification was used to establish nano-ripple structure on the Fe-30Mn alloy surface in this work. After laser texturing, typical nano-ripple structures were established on the alloy surfaces. With the increase of laser average line fluence from 10 to 30 J cm−2, the nano-ripple period decreased and vertical sinuous grooves were formed on the surface, resulting in a high roughness value and a hydrophobic surface. Compared with the polished sample, the nano-ripple structure surface exhibited significant improvement of the actual biodegradation rate. Further, in vitro cell counting kit-8 test showed that the laser surface modification had few effects on the cytocompatibility of Fe-30%Mn alloy. The results indicate its great potential for physical surface modification of biodegradable metals.

The inverse Heusler compound Ti 2 CrSn with L 2 1 phase is predicted to be antiferromagnetic semiconductor with an indirect gap of 0.2 eV based on first principles and Boltzmann transport theory. The semiconducting character is stable within a large strain from −6% to 6%. The Cr, Ti 1 and Ti 2 moments all show a linear change behavior within the strain range of −6% ∼ 6%, however, the total zero moment is robust within that strain range. It should be a potential candidate for applying to magnetic tunnel junction device. The total zero moment originates from the fully occupied 9 orbitals for both up and down spin directions below the Fermi level. The spin dependent 3d hybridization feature is found that for up spin states the hybridization between Cr and Ti 2 is dominant while for down spin states the hybridization between Ti 1 and Ti 2 is dominant, however, there is no clear indication of hybridization between Cr and Ti 1 . The gap origin of the spin up (down) direction is that the 3d hybridization of Cr − Ti 2 ( Ti 1 − Ti 2 ) forms the bonding three degenerate t 2 g as well as two degenerate e g below the Fermi level, and also corresponding antibonding states of them above the Fermi level. This hybridization character also can be seen from the electron density difference that only the region between Cr and Ti 2 , and between Ti 1 and Ti 2 show clear electrons accumulation suggesting strong interaction. The calculated value of thermoelectric power factor is near to that of Bi 2 Te 3 , marking its potential application values in thermoelectric field.

This paper presents a simple one-step method for the fabrication of size-controlled Br-doped TiO 2 nanoparticles via a hydrothermal method. The as-prepared Br-doped TiO 2 photocatalysts were characterized using X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), N 2 desorption–adsorption measurements, X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible (UV–vis) spectroscopy. The results indicate that the size of the Br-doped TiO 2 nanoparticles would decrease with increasing Br-doping concentration. The minimum size of the nanoparticles is approximately 4 nm. The as-prepared Br-doped TiO 2 photocatalyst is composed of the anatase and brookite phases. The Br-doping could efficiently narrow the band gap and broaden the visible-light response region. The dye on the surface of Br-doped TiO 2 could improve the photocatalytic performance during cyclic utilization because of the dye activation.

A micro–nano structured titanium (Ti) surface consisting of titania (TiO2) and hydroxyapatite (HA) was produced by one-step micro-arc oxidation (MAO) to improve the corrosion resistance and biological properties. The corrosion resistance was evaluated in simulated body fluids (SBF) by electrochemical impedance spectroscopy (EIS) and anodic polarisation tests. The biological properties were investigated by in vitro cell co-culture experiments and in vivo experiments. The results showed that a microstructured TiO2 coating loaded with a nanostructured HA slice could be obtained on the Ti substrate during the MAO process. The MAO induced composite coating showed an increased resistance value and corrosion potential. It also promoted the cell behaviors (proliferation and spreading) on the Ti surface. After implantation in the rat tibias, the bonding strength between the bone tissues and implant was enhanced. The improved corrosion resistance was attributed to the increased thickness of the oxide layer, and the enhanced biological properties resulted from the micro–nanostructure and HA on the Ti surface. Based on these results, it was concluded that the micro–nano structured Ti surface consisting of TiO2 and HA prepared by MAO has great potential to be applied in the clinic.

Two nonmagnetic Heusler-type semiconductors Ti 2 CrGe and Ti 2 CrSn (∼0.25 eV gap width) with good thermoelectric properties have been predicted based on first principles as well as Boltzmann transport theory. For both of the two compounds, the hole doping can obtain comparatively high PF than that of electron doping. With the enhancement of temperature, the peak value of Seebeck coefficient decreases while the power factor increases for both electron doping and hole doping. At room temperature (300 K), the maximum value of power factor 51.38 (1014 μW cm−1 K−2 S−2) and 47.53 (1014 μW cm−1 K−2 S−2) within the hole doping range of 1027 ∼ 1028 m−3 are obtained for Ti2CrGe and Ti2CrSn, respectively. Therefore, the two compounds belong to potential candidates for thermoelectric application because their power factor is close to that of the well known thermoelectric material Bi2Te3 which has been commercially for thermoelectric device.

The hierarchical micro-nanostructure has been proved to endow titanium (Ti) surface with good biological properties. However, to achieve satisfied osseointegration, good corrosion resistance and mechanical properties are also necessary. Therefore, in this paper, the corrosion resistance and mechanical properties of the Ti implant with hierarchical micro-nanostructure were investigated. The corrosion resistance was detected by polarization curve test, and the mechanical properties were evaluated by friction-wear experiment and nano indentation test. The results showed that the micro-nanostructured Ti surface showed increased corrosion potential, and it also showed decreased friction coefficient, stiffness and Young´s modulus, similar to that of the cortical bone. The improved corrosion resistance and mechanical properties might endow the micro-nanostructured Ti implant with good osseointegration and promising application in clinic.

Titanium (Ti) is a widely used implant material in clinics; however, failures still frequently occur due to its bioinertness and poor antibacterial capability. Post-implant infections most likely occur within the first two weeks. Thereafter, the host immune system lowers the infection risk, and biosafety becomes the first consideration. Therefore, endowing biomedical Ti with a time-dependent bactericidal effect is of considerable interest. In this study, Ag nanoparticles (NPs) as the antibacterial agent were incorporated deeply into TiO2 nanotubes prepared on the sandblasted and etched (SLA) Ti surface. The incorporated Ag NPs were verified to automatically transform from a free state to an immobilized state, rendering the constructed platform exhibit a self-adjusting antibacterial effect. It showed strong "release bactericidal" activity in the early phase that gradually changed to the "contact bactericidal" ability. Such a smart alteration could satisfy the varied antibacterial requirements in different periods after biomaterial implantation. Moreover, the nanotubular structure could accelerate apatite formation and improve cell adhesion and proliferation when compared with those of commercially used SLA implants. Based on these results, it can be concluded that Ag-NP-incorporated micro-nanostructured Ti has worthwhile biological and time-dependent antibacterial properties, and it can have promising applications in orthopedics, dentistry, and fabrication of other biomedical devices.

The MXene combining high surface area, prominent biocompatibility, and wide near infrared (NIR) absorption has been recognized as one of the most promising materials for tumor therapy. The application of MXene in tumor therapy is negatively affected by the current design methods lack the control of size distribution and the great tendency to agglomerate as well as poor photodynamic therapy. To solve the above problems, we report a facile strategy to process Ti3C2 nanosheets into three-dimensional (3D) structure with honeycomb structure and anti-aggregation properties for synergistic therapy of chemotherapy, photothermal and photodynamic therapy. The 3D MXene is synthesized by spray drying, in which the MXene surface is oxidized to TiO2. The microspheres present prominent NIR light trigger photothermal effect and excellent NIR light photostability, which respond in an on–off manner. Moreover, the microspheres exhibit outstanding drug-loading capability of doxorubicin (DOX) as high as 87.3%, and substantial singlet oxygen generation (1O2) was shown under 808 nm laser and UV light irradiation. Our studies indicate that 3D MXene-DOX could effectively achieve Hela cells killing in vitro, which provides a multifunctional drug delivery platform as a prospective candidate for future combined cancer therapy.

A proper immune response is a key to successful implantation of biomaterials. Since the dynamic changes of the human body's microenvironment, the required immune response should alter along with the microenvironment. A thermo-sensitive hydrogel composed of biocompatible hydroxypropyl methylcellulose (HMPC), chitosan (CS), and glycerin (Gly) was introduced on the anodized titanium surface to regulate the immune response. The results showed that the encapsulated hydrogel can cause macrophages to polarize toward the M2 phenotype, and promote tissue repair in the sol state at normal body temperature, while at the high-temperature induced by a bacterial infection, it will turn to a gel state, and can cause macrophages to polarize toward the M1 phenotype, promote inflammation, to realize an intelligent identification and regulation of the physiological environment, thus to satisfy the changeable immunity demands. By changing the temperature of the thermosensitive hydrogel, the transformation between macrophages M1 and M2 could be achieved, and the tissue could be transferred between the inflammatory stage and the healing stage promptly to achieve the purpose of antibiosis or tissue repair. The immunomodulatory effect of the thermo-sensitive hydrogel was verified to be related to the varied HMPC, CS, and Gly release in the sol and gel states.

CuS nanosheets and their various assembled forms prepared by dealloying a Ti-Cu amorphous alloy have been investigated as electrochemical pseudocapacitor materials for energy storage applications. The properties of the assembled forms of the CuS nanosheets are determined by using the concentration of H 2 SO 4 employed in the dealloying process. Spherical clusters composed of CuS nanosheets were fabricated by this process. These clusters have the highest specific surface areas provided by the nanosheets and exhibit high electrochemical and charge storage-release performances. The CuS spherical clusters showed a high specific capacitance of ∼276 F g −1 (at a scan rate of 5 mV s −1 in cyclic voltammetry tests) and ∼713 F g −1 (at a charge-discharge current of 1.0 A g −1 ). The high pseudocapacitive performance can be attributed to the highest specific surface area in our case and absence of volume change of the nanosheets. These results suggest the importance of a rational nanostructure design for high-performance energy applications.

Carbon nanotube (CNT)-reinforced hydroxyapatite (HA) composites were successfully fabricated by a double in situ synthesis process, which combined the in situ synthesis of CNTs in HA powders by chemical vapor deposition (CVD) with the further encapsulation of CNTs using HA by a sol–gel method. This double in situ synthesis approach not only improves the homogeneous dispersion of CNTs within the HA matrix, but also enhances the interfacial bonding between the CNTs and HA, thus leading to enhanced mechanical properties. Flexural tests indicated that the flexural strength of the composite is 1.6 times higher than that of pure HA, and significantly higher than that of the commercial and in situ synthesized CNT/HA composites. Furthermore, the in vitro cell culture experiments indicated that the CNT/HA composites fabricated by this double in situ process significantly accelerate the proliferation of fibroblast cells (L-929), compared with those fabricated by traditional methods, confirming their biocompatibility. With this biocompatibility and excellent mechanical properties, the obtained CNT/HA composites have a high potential as biomaterials, particularly in bone tissue engineering applications.

Anodic oxidation was applied to prepare the nanostructured titanium surface with different roughnesses and hydrophilicities. The morphology was characterized by scanning electron microscopy (SEM). The surface roughness was tested by atomic force microscopy (AFM), and the hydrophilicity was assessed from the contact angle between the deionized water and sample surface at room temperature. The results show that surface morphologies change remarkably with applied voltage and oxidation time during anodic oxidation. Under optimized oxidation conditions, well-ordered nanotube arrays were fabricated on the Ti surface. Roughness values increase with increase of the oxidation time, ranging from several dozen to several hundred nanometers, while the influence of voltage on surface roughness is not obvious. The hydrophilicity increases initially with the increase of oxidation time, but then decrease. The variations of surface morphology, roughness and hydrophilicity are correlated to the reactions occurring during the anodic oxidation.

A hydroxyapatite (HA)/TiO2 composite coating was prepared on a titanium surface by one-step micro-arc oxidation (MAO). The formation mechanism of the composite coating was investigated and the adhesion of the coating to the substrate was also measured. The results showed that flocculent structures could be obtained during the early stages of treatment. As the treatment period extended, increasing amounts of Ca–P precipitate appeared on the surface, and the flocculent morphology transformed into a plate-like morphology. Then the plate-like calcium and phosphate salt self-assembled to form flower-like apatite. The Ca/P atomic ratio gradually decreased, indicating that the amounts of Ca2+ ions which diffused into the coating decreased more rapidly than that of PO43− or HPO42−. The adhesive strength between the apatite and TiO2 coating was improved. This improvement is attributed to the interlocking effect between the apatite and TiO2 layer which formed simultaneously during the early stages of the one-step MAO. This study shows that it is a promising method to prepare bioactive coating on a titanium surface.

Electrospun composite nanofibrous scaffolds have been regarded as a potential carrier for local drug delivery to prevent tumor recurrence. Herein, a model drug (paclitaxel) was creatively loaded into lignin nanoparticles (PLNPs) and then encapsulated into the polymer of poly (vinyl alcohol)/polyvinyl pyrrolidone which has been fabricated into a composite nanofibrous membrane (PVA/PVP-PLNPs) for use as a drug carrier using the electrospinning technique. The fabricated PVA/PVP-PLNPs membranes exhibited good particle distribution, mechanical properties, thermal stability and biocompatibility. In vitro experiments showed that combining lignin nanoparticles by electrospinning not only improved the drug release profile, but also enhanced the hydrophilicity of nanofibrous membranes which was beneficial to cell adhesion and proliferation. Cellular experiments demonstrated that PVA/PVP-2%PLNPs membrane showed good cell inhibition ability, and the cell survival rate was only 21% at day 7. It indicates that the as-prepared PVA/PVP-PLNPs composite nanofibers are promising candidates for local anticancer therapy.

Novel Mg–graphene-nanoplatelet (GNP) composites were fabricated using the Rieke method to synthesize Mg in situ on the GNP surfaces and powder metallurgy (PM). Mg particles synthesized using the Rieke method were deposited on the surfaces of the GNPs during the displacement reaction between Li and anhydrous MgCl2, which yielded in situ Mg-encapsulated GNPs (GNPs@Mg) composite structures. In the GNPs@Mg composite structures, the displaced Mg was closely attached to the surfaces of the GNPs in a nanocrystallite form and achieved a close mechanical interfacial bonding with the GNPs. After employing the PM, the obtained GNPs@Mg composite powders were transformed into GNPs@Mg bulk composites, which ensured the integrity and dispersion of the GNPs in the Mg matrix. The mechanical properties of the GNPs@Mg bulk composite were significantly improved owing to the strengthening effects of the GNPs. The yield strength and ultimate tensile strength of a 1.5-wt.% GNPs@Mg bulk composite were approximately 38.8 and 35.1% higher than those of a pure Mg bulk, respectively, while the hardness and elongation to failure were increased by approximately 47.4 and 36.5%, respectively. Furthermore, the strengthening and toughening efficiencies of the GNPs@Mg bulk composites were significantly higher than those of GNPs/Mg composites fabricated using the conventional addition method. Therefore, this research provides new insights into the process design of high-performance lightweight structural metallic materials.

Magnesium/aluminium clad bars were fabricated by compound casting and multi-pass warm caliber rolling. A Ni interlayer prepared using a plasma spraying process was inserted between the parent metals to improve the interfacial characteristics during the casting process, and the effect of caliber rolling on the evolution of the interfacial microstructure and mechanical properties of the Mg/Ni/Al composites was investigated. The results show that the formation of Mg-Al intermetallic phases was impeded effectively by the Ni interlayer and a typical AZ31/Ni/6061 multilayer structure with metallurgical bonding was formed during the compound casting process. In addition, an inhomogeneous strain distribution in the AZ31 and 6061 alloys were characterized during the rolling process. The AZ31 clad layer accommodated a larger proportion of the plastic strain during the initial passes, while the strain in the Mg core layer increased with increasing number of passes. The Ni interlayer fragmented during the rolling process, and transformed into the dispersed particles at the interface. Meanwhile, the fresh AZ31 and 6061 base alloys squeezed out and bonded together under the rolling force, and a well-bonded interface with no visible defects was formed.

A novel nitrogen doped mesoporous carbon (NMPC) with a hierarchical porous structure is prepared by simple carbonizing the green algae, which is applied as a host material to encapsulate sulfur for lithium/sulfur (Li/S) battery. The NMPC exhibits high pore volume as well as large specific surface area, and thus sulfur content in the S/NMPC composite reaches up to 63 wt %. When tested in a Li/S battery, the S/NMPC composite yields a high initial capacity of 1327 mAh·g−1 as well as 757 mAh·g−1 after 100 cycles at a current rate of 0.1 C, a reversible capacity of 642 was achieved even at 1 C. This good electrochemical performance of the S/NMPC composite could be attributed to a unique combination of mesopority and surface chemistry, allowing for the retention of the intermediate polysuflides within the carbon framework.

The sliding behavior of interwalls between double-walled carbon nanotubes (DWCNTs) is studied by molecular dynamics (MD) simulations. The results show that a platinum (Pt) nanowire (NW) is able to push out a single wall from the DWCNT. The pushout process is strongly dependent on the match level of the NW radius and the inner wall CNT radius. The match radius of the Pt NW and the inner CNT wall will form perfect single-walled CNT (SWCNT) and Pt/CNT core/shell nanostructure. In addition, the bonding interactions between the Pt NW and the CNT are also studied. The shear stress between the Pt NW and CNT is in megapascal magnitude. The chirality has little effect on the interfacial bonding and the shear stress between the Pt NW and the CNT. This study will shed light on the understanding of the lubrication mechanism of the multi-walled CNT and the metal NWs in realistic situations.

The Br-doped hollow TiO2 photocatalysts were prepared by a simple hydrothermal process on the carbon sphere template following with calcination at 400 °C. The structure and properties of photocatalysts were characterized by X-ray diffraction, Raman spectrum, scanning electron microscope, transmission electron microscopy, N2 desorption–adsorption, UV–Vis spectroscopy, and X-ray photoelectron spectroscopy. The TiO2 hollow spheres are in diameter of 500 nm with shell thickness of 50 nm. The shell is composed of small anatase nanoparticles with size of about 10 nm. The TiO2 hollow spheres exhibit high crystalline and high surface area of 89.208 m2/g. With increasing content of Br doping, the band gap of TiO2 hollow spheres decreased from 2.85 to 1.75 eV. The formation of impurity band in the band gap would narrow the band gap and result in the red shift of absorption edge from 395 to 517 nm, which further enhances the photocatalytic activity. The appropriate Br doping improves the photocatlytic activity significantly. The TiO2 hollow spheres with 1.55% Br doping (0.5Br-TiO2) exhibit the highest photocatalytic activity under full light. More than 98% of RhB, MO, and MB can be photodegraded using 0.5Br-TiO2 with concentration of 10 mg/L in 40, 30, and 30 min, respectively. The degradation rate of Br-doped photocatalysts was 40% faster than undoped ones.

Carbon nanotube (CNT)-reinforced mesoporous hydroxyapatite (HA) composites with excellent mechanical and biological properties were fabricated successfully by the in situ chemical deposition of mesoporous HA on homogeneously dispersed CNTs. The CNTs are first synthesized in situ on HA nanopowders by chemical vapor deposition, and then, the HA particles with mesoporous structures are deposited in situ onto the as-grown CNTs by using cetyl trimethyl ammonium bromide as templates to form mesoporous HA encapsulated CNTs (CNT@meso-HA). The modification of CNTs by mesoporous HA leads to strong CNT-HA interfacial bonding, resulting in efficient load transfer between CNT and HA and improved mechanical properties of CNT/HA composites. More importantly, the mesoporous HA structure has a high specific surface area and large surface roughness that greatly promote the cell adhesion and proliferation, resulting in better biocompatibility and improved osteoblast viability (MC3T3-E1) compared to those fabricated by traditional methods. Therefore, the obtained CNT@meso-HA composites are expected to be promising materials for bone regeneration and implantation applications.

In this study, a novel photocatalyst composed of N-doped TiO2 (N-TiO2) and (Ca, Y)F2:Yb3+, Tm3+ was prepared by simple dealloying followed by a hydrothermal method. The composite exhibits a homogeneous nanoporous structure consisting of large quantities of the spindle-like N-doped TiO2 nanorods, on which the (Ca, Y)F2:Yb3+, Tm3+ particles with a diameter of around 5 nm are uniformly dispersed. In addition, morphology and property of the N-TiO2 can be controlled by adjusting the dealloying period. Results show that a short immersion time leads to a small size, large surface area and low band gap. As a result, the N-TiO2/(Ca, Y)F2:Yb3+, Tm3+ composite after dealloying for 48 h (TiO2-48-C) exhibits higher degradation rates (65.6% for 10 h irradiation by 980 nm NIR) than others after dealloying for 60 h (TiO2-60-C) and 72 h (TiO2-72-C), indicating its excellent potential for practical applications.

Carbon-encapsulated Fe-C (Fe-C@C) nanoparticles with a divergently flower-like morphology were successfully synthesized for application as an adsorbing material by using freeze-drying and chemical vapor deposition (CVD) methods. The Fe metallic source was first loaded onto a sodium chloride (NaCl) supporter via freeze-drying to obtain the Fe/NaCl composite powder. Then, Fe-C@C nanoparticles were synthesized in the temperature range of 300&ndash, 450 &deg, C via CVD of acetylene in the Fe/NaCl composite powder using Fe nanoparticles as catalysts and NaCl as supporters. Because the NaCl supporter is water-soluble, the synthesized Fe-C@C nanoparticles were easy to purify, and a high purity was obtained by simple washing and centrifugation. The optimal Fe-C@C nanoparticles, synthesized at 400 &deg, C, possessed a unique divergently flower-like structure and a high specific surface area of 169.4 m2/g that can provide more adsorption sites for contaminants. Adsorption experiments showed that the flower-like Fe-C@C adsorbent exhibited high adsorption capacity (90.14 mg/g) and fast removal of methylene blue (MB). Moreover, the magnetic properties of the nanoparticles, with saturation magnetization of 36.544 emu/g, facilitated their magnetic separation from wastewater. Therefore, the novel flower-like Fe-C@C nanoparticles with integrated adsorptive and magnetic properties have the potential to be an effective adsorbent in dye wastewater treatment.

The use of cardiovascular stents for rapid in vivo re-endothelialization is a promising strategy for reducing cardiovascular implantation or preventing local thrombus formation and restenosis. Surface-patterned intravascular endoprosthetic stents have been developed to prevent life-threatening complications. In this study, vascular smooth muscle cell (VSMC)-biomimetic surface patterns were fabricated on 316L cardiovascular stents using a femtosecond laser and then implanted into the iliac artery of rabbit. The in vitro data revealed that the bionic surface patterns matched the morphology of the VSMCs well, which promotes the adhesion, proliferation, and migration of human umbilical vein endothelial cells. In addition, the patterned surfaces can significantly enhance re-endothelialization. Consequently, the surface biomimetic stent with the VSMC surface pattern is likely an effective approach to ensure rapid re-endothelialization and possibly reduce the incidence of in-stent restenosis.

The structure and properties of nanostructured materials formed upon deformation are determined to a great extent by the states of stress and strain and the regimes of deformation. The nanostructures and properties of the graphene nanoribbons (GNRs) subjected to severe twist deformation were studied using molecular dynamics (MD) simulations. The GNRs show superflexibility and withstanding severe twisting, which leads to GNR nanostructures transforming from flat to twisted and then getting thoroughly coiled and fail. The appearance of a decreasing Young's moduli of the GNRs was observed with increasing rotation in general. The chirality has little effect on the Young's moduli of flat GNRs, whereas the degree of the GNR aspect ratio does. The severely twisted GNRs follow a similar rule but with slightly decreased Young's moduli (∼0.1 TPa), which demonstrates that the twisted GNRs maintain their stiff nature. The electronic properties of the GNRs under severely twisted conditions also show slight changes studied by density-functional theory (DFT) simulations. The stable mechanical properties and structure changes of GNRs under severely twisted conditions makes them a good candidate in some polymers, enhancing the load transfer and interfacial bonding by adding the twisted GNRs.

A three-dimensionally (3D) ordered macro-/mesoporous TiO2 (3DOM-mTiO2) was synthesized via a simple solvothermal process. 3DOM-mTiO2 was used as a sulfur carrier for cathode materials in a lithium-sulfur (Li-S) battery. The orderly interconnected macro and mesopores structure within the macropore walls yield a large pore volume and high specific surface area in 3DOM-mTiO2, which improved the sulfur loading capacity of the material. The S/TiO2 composite was synthesized as a cathode material for lithium/sulfur battery, which initially produced a high capacity of 1089 mAh g-1 and retained a value of 703 mAh g-1 after 200 cycles. An initial current rate of 0.2 C was used, which was further increased up to 2.5 C when a reversible capacity of 651 mAh g-1 was obtained. The excellent electrochemical performance can be attributed to the 3D ordered macro-/mesoporous structure of TiO2, which physically confines the soluble lithium polysulfides and diminishes the sulfur volume expansion upon cycling. In addition, the strong electrostatic attraction between the Ti-O bond and polysulfide stimulates the performance via stronger adsorption of the electrochemical reaction products.

A nanostructured carbon (NSC) material with a hierarchical porous structure is synthesized through the carbonization of a waterweed, namely Echinodorus amazonicus Rataj. The fabricated NSC is used as an electrode material for sulfur of lithium/sulfur (Li/S) batteries. The NSC provides for a high pore volume (0.19 cm3 g&minus, 1) and large specific surface area (111.25 m2 g&minus, 1). Because of the highly hierarchical porous structure of the NSC material, allowing polysulfides to remain in the carbon framework after cycling, the sulfur/NSC composite exhibits an excellent electrochemical performance.