Bidirectional enhancement of Li2S redox reaction by NiSe2/CoSe2-rGO heterostructured bi-functional catalysts.

The high activity barriers of Li2S nucleation and deposition limit the redox reaction kinetics of lithium polysulfides (LiPSs), meanwhile, the significant shuttle effect of LiPSs hampers the advancement of Li-S batteries (LSBs). In this work, a NiSe2/CoSe2-rGO (NiSe2/CoSe2-G) sulfur host with bifunctional catalytic activity was prepared through a hard template method. Electrochemical experiment results confirm that the combination of NiSe2 and CoSe2 not only facilitates the bidirectional catalytic function during charge and discharge processes, but also increases the active sites toward LiPSs adsorption. Simultaneously, the highly conductive rGO network enhances the electronic conductivity of NiSe2/CoSe2-G/S and provides convenience for loading NiSe2/CoSe2 catalysts. Benefitting from the exceptional catalytic-adsorption capability of NiSe2/CoSe2 and the presence of rGO, the NiSe2/CoSe2-G/S electrode exhibits excellent electrochemical properties. At 1C, it demonstrates a low capacity attenuation of 0.087 % per cycle during 500 cycles. The electrode can maintain a discharge capacity of 927 mAh/g at a sulfur loading of 3.3 mg cm-2. The bidirectional catalytic activity of NiSe2/CoSe2-G offers a prospective approach to expedite the redox reactions of active S, meanwhile, this work also offers an ideal approach for designing efficient S hosts for LSBs.

High performance rechargeable aqueous zinc-iodine batteries via a double iodine species fixation strategy with mesoporous carbon and modified separator.

With the increasing requirement for high capacity energy storage systems, a large amount of recent work has focused on the development of zinc-iodine batteries (ZIBs) on account of high energy density, fast redox kinetics, and excellent reversibility. Nevertheless, low electron conductivity, the shuttle effect, and highly soluble iodine species (I2, I-, and I3-) have impeded their widespread application. In this study, metal organic framework-5 (MOF-5)-derived mesoporous carbon (MPC) loaded iodine (MPC/I2) cathode and the single-sided ketjen black modified cotton fiber (KB@CF) separator are designed to solve the problems mentioned above. That is, the double fixation strategy using MPC and KB@CF separators for iodine species suppresses the shuttle effect. Therefore, the ZIBs constructed with the MPC/I2 cathode and the KB@CF separator can exhibit excellent electrochemical performance. At the current density of 0.1 A g-1, a high discharge specific capacity of 137 mAh g-1 is still available after 300 cycles. Meanwhile, it exhibits a low capacity decay rate at long cycling (0.030% per cycle over 2000 cycles).

ZIF-8 derived porous carbon to mitigate shuttle effect for high performance aqueous zinc-iodine batteries.

Rechargeable aqueous zinc-iodine batteries (ZIBs) with low environmental impacts and abundant natural reserves have emerged as promising electrochemical energy storage devices. However, the shuttle effect and low conductivity of the iodine species cause poor electrochemical performance and hinder their practical application. Herein, we propose a ZIF-8 derived porous carbon (ZPC) for iodine species immobilization in ZIBs. The rich porous structure and highly conductive framework of ZPC provide efficient iodine loading and allow the fast transmission of electrons. In addition, the presence of N, Zn and ZnO in the carbon framework can build chemical anchoring with the iodine species to mitigate the shuttle effect. Thus, the ZPC/I2 cathode exhibits a reversible capacity of 156 mAh g-1 after 100 cycles at 100 mA g-1 and a long-term stability of 1000 cycles at a high rate. This study will open a new paradigm for devolving highly reversible ZIBs.

High-performance reversible aqueous zinc-ion battery based on iron-doped alpha-manganese dioxide coated by polypyrrole.

The development of zinc-ion storage cathode materials for aqueous zinc-ion batteries (AZIBs) is a necessary step for the construction of large-scale electrochemical energy conversion and storage devices. Iron-doped alpha-manganese dioxide (α-MnO2) nanocomposites were achieved in this study via pre-intercalation of Fe3+ during the formation of α-MnO2 crystals. A polypyrrole (PPy) granular layer was fabricated on the surface of α-MnO2 using acid-catalyzed polymerization of pyrroles. The pre-intercalation of Fe3+ effectively enlarges the lattice spacing of α-MnO2 and consequently decreases the hindrance for Zn2+ insertion/extraction in the iron-doped α-MnO2 coated by PPy (Fe/α-MnO2@PPy) composite. Meanwhile, the PPy buffer layer can ameliorate electron and ion conductivity and prevent dissolution of α-MnO2during the charge/discharge process. This unique structure makes the Fe/α-MnO2@PPy composite an efficient zinc-ion storage cathode for AZIBs. The targeted Fe/α-MnO2@PPy cathode achieves superior performance with reversible specific capacity (270 mA h g-1 at 100 mA g-1) and exhibits highdiffusioncoefficientof 10-10-10-14 cm-2 s-1. Therefore, a feasible approach is implemented on advanced electrode materials using in AZIBs for practical applications.

Baicalein inhibits inflammatory response and promotes osteogenic activity in periodontal ligament cells challenged with lipopolysaccharides.

BACKGROUND: Periodontitis is a chronic infection initiated by oral bacterial and their virulence factors, yet the severity of periodontitis is largely determined by the dysregulated host immuno-inflammatory response. Baicalein is a flavonoid extracted from Scutellaria baicalensis with promising anti-inflammatory properties. This study aims to clarify the anti-inflammatory and osteogenic effects of baicalein in periodontal ligament cells (PDLCs) treated with lipopolysaccharides (LPS). METHODS: Human PDLCs were incubated with baicalein (0-100 µM) for 2 h prior to LPS challenge for 24 h. MTT analysis was adopted to assess the cytoxicity of baicalein. The mRNA and protein expression of inflammatory and osteogenic markers were measured by real-time polymerase chain reaction (PCR), western blot and enzyme-linked immunosorbent assay (ELISA) as appropriate. Alkaline phosphatase (ALP) and Alizarin red S (ARS) staining were performed to evaluate the osteogenic differentiation of PDLCs. The expression of Wnt/ß-catenin and mitogen-activated protein kinase (MAPK) signaling related proteins was assessed by western blot. RESULTS: MTT results showed that baicalein up to 100 µM had no cytotoxicity on PDLCs. Baicalein significantly attenuated the inflammatory factors induced by LPS, including interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), matrix metalloprotein-1 (MMP-1), MMP-2 and monocyte chemoattractant protein 1 (MCP-1) at both mRNA and protein level. Moreover, MAPK signaling (ERK, JNK and p38) was significantly inhibited by baicalein, which may account for the mitigated inflammatory response. Next, we found that baicalein effectively restored the osteogenic differentiation of LPS-treated PDLCs, as shown by the increased ALP and ARS staining. Accordingly, the protein and gene expression of osteogenic markers, namely runt-related transcription factor 2 (RUNX2), collagen-I, and osterix were markedly upregulated. Importantly, baicalein could function as the Wnt/ß-catenin signaling activator, which may lead to the increased osteoblastic differentiation of PDLCs. CONCLUSIONS: With the limitation of the study, we provide in vitro evidence that baicalein ameliorates inflammatory response and restores osteogenesis in PDLCs challenged with LPS, indicating its potential use as the host response modulator for the management of periodontitis.

CoCl2 induced hypoxia enhances osteogenesis of rat bone marrow mesenchymal stem cells through cannabinoid receptor 2.

OBJECTIVES: This study aims to investigate the role of Cannabinoid receptor 2 (CB2) on osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs) under hypoxia. MATERIALS AND METHODS: BMSCs were isolated from Sprague-Dawley rats and cultured in the presence of cobalt chloride (CoCl2) to induce intracellular hypoxia. Cell proliferation was measured with MTT assay. Quantitative real-time PCR and western blot were applied to evaluate the mRNA and protein expressions of CB2 and osteogenic indicators including osteocalcin, RUNX2, collagen-1 and osterix (SP7). The osteogenic differentiation of BMSCs was further examined by ALP assay and alizarin red S (ARS) staining. Moreover, the activation of MAPKs signaling pathways was analyzed by western blot. RESULTS: CoCl2 dose-dependently increased hypoxia inducible factor while higher concentrations (200 and 400 µM) of CoCl2 markedly inhibited cell proliferation. CoCl2 induced hypoxia significantly increased the protein and mRNA expressions of osteocalcin, RUNX2, collagen-1 and osterix, along with enhanced ALP and ARS staining. Interestingly, such effects can be inhibited by the addition of CB2 inhibitor AM630. Moreover, AM630 partially inhibited hypoxia-induced p38 and ERK pathways, which may lead to a decrease in the osteogenic transcripts of RUNX2, collagen-1 and osterix. CONCLUSIONS: CoCl2 induced hypoxia could promote osteogenesis of rat BMSCs possibly through CB2.

Metal-Organic Framework/Polythiophene Derivative: Neuronlike S-Doped Carbon 3D Structure with Outstanding Sodium Storage Performance.

Herein, a metal-organic framework (MOF)/polythiophene (PTh)-derived S-doped carbon is successfully designed and prepared employing zeolitic imidazolate frameworks (ZIF-8/ZIF-67) and thiophene (Th) as precursors. The S-doped carbon presents a neuronlike three-dimensional network structure (3DSC). The 3DSC delivers extra-high capacities (225 mAh/g at 5000 mA/g after 3000 cycles) and excellent endurance ability of current changes when applied in Na-ion batteries (SIBs). Moreover, when the 3DSC-700 anode is coupled with a sodium vanadium phosphate cathode to construct a Na-ion full cell, after 50 cycles, a high capacity of ∼229.64 mAh/g is obtained at 100 mA/g. Electrochemical impedance spectroscopy analysis, density functional theory calculations, and pseudocapacitance contributions are adopted to investigate the excellent sodium storage mechanism of the 3DSC electrode. A new idea has been provided in this work to open up the possibility of MOF materials and carbon-based materials applications in SIBs in the future.

Porous Core-Shell CuCo2 S4 Nanospheres as Anode Material for Enhanced Lithium-Ion Batteries.

Porous core-shell CuCo2 S4 nanospheres that exhibit a large specific surface area, sufficient inner space, and a nanoporous shell were synthesized through a facile solvothermal method. The diameter of the core-shell CuCo2 S4 nanospheres is approximately 800 nm" the radius of the core is about 265 nm and the thickness of the shell are approximately 45 nm, respectively. On the basis of the experimental results, the formation mechanism of the core-shell structure is also discussed. These CuCo2 S4 nanospheres show excellent Li storage performance when used as anode material for lithium-ion batteries. This material delivers high reversible capacity of 773.7 mA h g-1 after 1000 cycles at a current density of 1 A g-1 and displays a stable capacity of 358.4 mA h g-1 after 1000 cycles even at a higher current density of 10 A g-1 . The excellent Li storage performance, in terms of high reversible capacity, cycling performance, and rate capability, can be attributed to the synergistic effects of both the core and shell during Li+ ion insertion/extraction processes.

[Hypoxia regulates the expression of OPG/RANKL mRNA in rat bone marrow mesenchymal stem cells].

PURPOSE: To investigate the effects of hypoxia on the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) mRNA in rat bone marrow mesenchymal stem cells (rBMSCs). METHODS: rBMSCs were isolated and cultured by whole bone marrow cell adherent method, and an optimal hypoxic preconditioning model was established with CoCl2 (cobalt chloride). rBMSCs were incubated in cell culture mediums with different concentrations of CoCl2 (final concentrations of CoCl2 were 0, 50, 100, 200, 400 µmol/L) and incubated for different times. MTT assay was applied to detect the effect of CoCl2 on cell proliferation. mRNA and protein expression of HIF-1α of rBMSCs was detected by real-time PCR and Western blot. After treated with 100 µmol/L CoCl2 for 0, 12, 24, 48, 72, 96 h, the expression of rBMSCs OPG/RANKL mRNA were detected by real-time PCR. The differences in distribution of each genotype were analyzed with SPSS 18.0 software package. RESULTS: Compared with the control group, 200, 400 µmol/L CoCl2 inhibited the proliferation of rBMSCs (P<0.05). However, 50, 100 µmol/L CoCl2 had no significant impact on the proliferation of rBMSCs (P>0.05). Real-time PCR and Western blot showed that HIF-1α expression in 50 µmol/L and 100 µmol/L CoCl2 groups was significantly higher than the control group; the effect of 100 µmol/L CoCl2 was significantly greater than 50 µmol/L CoCl2. After cultivated in hypoxia condition for 12 h, the expression of OPG and RANKL mRNA in rBMSCs didn't change significantly (P>0.05). After cultured hypoxia condition for 24, 48, 72, 96 h, the expression of OPG mRNA in rBMSCs increased while the RANKL decreased, thus the ratio of OPG/RANKL increased and the difference was significant (P<0.05). CONCLUSIONS: Hypoxia can regulate the mRNA expression of OPG and RANKL mRNA in rBMSCs and significantly promote osteogenic differentiation.

Individualized intervention to reduce anxiety in adult orthodontic patients based on Q methodology.

INTRODUCTION: In this study, we used Q methodology to assess the concerns of adults seeking orthodontic treatment and to determine individualized interventions to reduce their anxiety. METHODS: Statements of concern were derived by in-depth interviews with 70 adult patients. Q sorting methodology was then used to identify the main factors associated with anxiety in a cohort of 40 adults who had not been involved in the first part of the study. The final stage involved a randomized study in which 160 new adult patients were recruited and randomized into intervention and control groups. Participants in the intervention group sorted the statements, after which individualized interventions were implemented. Participants in the control group received routine treatment. The State-Trait Anxiety Inventory was used to measure changes in participants' anxiety levels before and during treatment. RESULTS: In total, 41 statements were identified, and participants were classified according to 5 factors. Factor 1 participants were concerned about the lack of treatment information; factor 2 represented concerns about cost and other people's opinions; factor 3 represented concerns about impact on work related to wearing braces; factor 4 encompassed concerns about treatment effects, pain, and dental fears; and factor 5 reflected concerns about side effects and finding a partner. The mean state anxiety inventory scores for both the intervention and control groups were highest 24 hours after bonding (intervention group, 44.63 ± 4.49; control group, 49.43 ± 5.42). The intragroup state anxiety inventory scores differed significantly across the 6 time points (P <0.01), with the state anxiety inventory scores of the intervention group significantly lower than those of the control group (P <0.01) at all time points except baseline. No significant intergroup or intragroup differences were found in relation to trait anxiety. CONCLUSIONS: Adult orthodontic patients expressed diverse concerns. Individualized interventions based on Q methodology may reduce anxiety in this patient population.

Baicalein enhances the osteogenic differentiation of human periodontal ligament cells by activating the Wnt/ß-catenin signaling pathway.

OBJECTIVE: Periodontium regeneration is one of the most important processes for periodontitis therapy. Human periodontal ligament cells (hPDLCs) play a vital role in the repair and regeneration of periodontal tissues. Our study aimed to investigated the mechanisms underlying the promotion of hPLDCs osteogenic differentiation by baicalein. DESIGN: hPDLCs were obtained from periodontal ligament (PDL) tissues by primary culture. The MTT assay was used to determine the growth curves of hPDLCs treated with different concentrations of baicalein (1.25, 2.5, 5, or 10µM). Alkaline phosphatase (ALP) staining and Alizarin red S staining were performed to assess osteogenic differentiation of hPDLCs administered baicalein. Osteogenic differentiation-related gene and protein expression levels and Wnt/ß-catenin pathway signal changes were assessed by qRT-PCR and Western blotting analysis. RESULTS: The results showed that baicalein decreased the growth of hPDLCs slightly and increased ALP activity and calcium deposition in a dose-dependent manner. The expression of runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP2), Osterix (OSX) and osteocalcin (OCN) were elevated after baicalein administration. Moreover, baicalein strongly activated the Wnt/ß-catenin pathway and up-regulated the expression of ß-catenin, lymphoid enhancer factor 1 (LEF1) and Cyclin D1. Dickkopf-related protein 1 (DKK-1) significantly reversed the effects of baicalein on hPDLCs. CONCLUSIONS: Our findings indicated that baicalein enhanced the osteogenic differentiation of hPDLCs via the activation of the Wnt/ß-catenin signaling pathway, which may represent a potential candidate for periodontitis therapy.

Psychosocial impact of dental esthetics regulates motivation to seek orthodontic treatment.

INTRODUCTION: The aim of this study was to evaluate the psychosocial impact of dental esthetics for adults seeking orthodontic treatment. METHODS: The Chinese version of the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) was administered to 393 adults, aged 18 to 30 years. The participants were divided into 2 groups: an intervention group (received orthodontic treatment) and a control group (rejected orthodontic treatment). Baseline malocclusion severity was assessed using the Index of Orthodontic Treatment Need (IOTN). RESULTS: The Wilcoxon signed rank test showed no statistically significant difference between the groups for the dental health component (DHC) of the IOTN (P = 0.134). Total and subscale PIDAQ scores of the intervention group were higher than those of the control group and differed significantly in each group among the 4 IOTN-DHC grades; self-confidence scores in the control group (F = 1.802; P >0.05) were the exception. Correlations between the PIDAQ scores and the IOTN-DHC grades were strong in each group. DHC grades, psychological impact, social impact, and aesthetic concern had significant impacts on patients accepting orthodontic treatment. CONCLUSIONS: The psychosocial impact of dental esthetics played an important role in the decision-making process of adults seeking orthodontic treatment. Importantly, participants with low self-awareness of the potential psychosocial impact rejected orthodontic treatment, despite the need for severe normative treatment.

Combined effects of proinflammatory cytokines and intermittent cyclic mechanical strain in inhibiting osteogenicity in human periodontal ligament cells.

Mechanical strain plays an important role in bone formation and resorption during orthodontic tooth movement. The mechanism has not been fully studied, and the process becomes complex with increased amounts of periodontal patients seeking orthodontic care. Our aims were to elucidate the combined effects of proinflammatory cytokines and intermittent cyclic strain (ICS) on the osteogenic capacity of human periodontal ligament cells. Cultured human periodontal ligament cells were exposed to proinflammatory cytokines (interleukin-1ß 5 ng/mL and tumor necrosis factor-α 10 ng/mL) for 1 and 5 days, and ICS (0.5 Hz, 12% elongation) was applied for 4 h per day. The autocrine of inflammatory cytokines was measured by enzyme-linked immunosorbent assay. The expression of osteoblast markers runt-related transcription factor 2 and rabbit collagen type I was determined using real-time polymerase chain reaction and Western blot. The osteogenic capacity was also detected by alkaline phosphatase (ALP) staining, ALP activity, and alizarin red staining. We demonstrated that ICS impaired the osteogenic capacity of human periodontal ligament cells when incubated with proinflammatory cytokines, as evidenced by the low expression of ALP staining, low ALP activity, reduced alizarin red staining, and reduced osteoblast markers. These data, for the first time, suggest that ICS has a negative effect on the inductive inhibition of osteogenicity in human PDL cells mediated by proinflammatory cytokines.

Endogenous hydrogen sulfide is involved in osteogenic differentiation in human periodontal ligament cells.

OBJECTIVE: Endogenous hydrogen sulfide (H2S) has recently emerged as an important intracellular gaseous signaling molecule within cellular systems. Endogenous H2S is synthesized from l-cysteine via cystathionine ß-synthase and cystathionine γ-lyase and it regulates multiple signaling pathways in mammalian cells. Indeed, aberrant H2S levels have been linked to defects in bone formation in experimental mice. The aim of this study was to examine the potential production mechanism and function of endogenous H2S within primary human periodontal ligament cells (PDLCs). DESIGN: Primary human PDLCs were obtained from donor molars with volunteer permission. Immunofluorescent labeling determined expression of the H2S synthetase enzymes. These enzymes were inhibited with D,L-propargylglycine or hydroxylamine to examine the effects of H2S signaling upon the osteogenic differentiation of PDLCs. Gene and protein expression levels of osteogenic markers in conjunction with ALP staining and activity and alizarin red S staining of calcium deposition were used to assay the progression of osteogenesis under different treatment conditions. Cultures were exposed to Wnt3a treatment to assess downstream signaling mechanisms. RESULTS: In this study, we show that H2S is produced by human PDLCs via the cystathionine ß-synthase/cystathionine γ-lyase pathway to promote their osteogenic differentiation. These levels must be carefully maintained as excessive or deficient H2S levels temper the observed osteogenic effect by inhibiting Wnt/ß-catenin signaling. CONCLUSIONS: These results demonstrate that optimal concentrations of endogenous H2S must be maintained within PDLCs to promote osteogenic differentiation by activating the Wnt/ß-catenin signaling cascade.

Prediction of pain in orthodontic patients based on preoperative pain assessment.

AIM: To investigate whether pretreatment assessment of experimental pain can predict the level of pain after archwire placement. METHODS: One hundred and twenty-one general university students seeking orthodontic treatment were enrolled in this study. A cold pressor test was performed to estimate the pain tolerance of subjects before treatment. Self-reported pain intensity was calculated using a 10 cm visual analog scale during the 7 days after treatment. The relationship between pain tolerance and orthodontic pain was analyzed using Spearman's correlation analysis. RESULTS: The maximum mean level of pain intensity occurred at 24 hours after bonding (53.31±16.13) and fell to normal levels at day 7. Spearman's correlation analysis found a moderate positive association between preoperative pain tolerance and self-reported pain after archwire placement (P<0.01). There was no significant difference in pain intensity between male and female patients at any time point (P>0.05). CONCLUSION: A simple and noninvasive preoperative sensory test (the cold pressor test) was useful in predicting the risk of developing unbearable pain in patients after archwire placement. Self-reported pain after archwire placement decreased as individual pain tolerance increased.

The treatment timing of labial inversely impacted maxillary central incisors: A prospective study.

OBJECTIVE: To determine the timing of treatment for the labial inversely impacted maxillary central incisors. METHODS: Twenty-eight patients (mean age, 8.2 years) with labial inversely impacted maxillary central incisors were divided into early-treated and later-treated groups according to their dental age. All of the patients were treated with a combination of surgery and orthodontic traction using the Guide rod appliance. Cone-beam computed tomography images were taken immediately after treatment for assessing the root morphology, root length, and alveolar bone loss. Sagittal slices were evaluated at the widest labial-lingual width of the tooth in the axial view. All variables were evaluated by Simplant 13.0 software (Materialise Dental NV, Leuven, Belgium). RESULTS: The rank sum test indicated that the root length of two groups showed a statistically significant difference between the impacted and homonym tooth, with a shorter length in the impacted tooth (P < .05). The D-value (difference of root length between the impacted and homonym tooth) and alveolar bone loss on the labial side of the impacted incisor are significantly less in the early-treated groups when compared with the later-treated groups (P < .05). Spearman rank correlation analysis showed a statistically positive association between the treatment timing and D-value (r  =  .623, P < .05). The chi-square test for morphology of root apex indicated that the incidence of the root-apex-directed labial side is significantly higher in the later-treated groups when compared with the early-treated groups. CONCLUSION: The labial inversely impacted maxillary central incisors should be treated early to promote root development by achieving a better morphology of root apex, thus reducing the risk of alveolar bone loss on the labial side.

[The influence of zoledronic acid on vascular endothelial cell].

OBJECTIVE: To investigate the influence of zoledronic acid on vascular endothelial cells. METHODS: The influence of zoledronic acid on proliferation, migration and adhesion of vascular endothelial cells were tested with 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cell migration assay and cell adhesion assay. The results of each experimental group were compared with the control group and the data statistically analyzed. RESULTS: In a concentration of 0-0.5 mmol/L, the absorbance value decreased from 0.09 to 0.34 as the drug concentration increased. Scratch test showed that the change of width of scratch before and after 24 hours in control, low, medium and high concentration groups were (38.7 ± 0.42), (35.8 ± 4.17), (19.9 ± 0.57) mm (P < 0.001), (12.5 ± 3.89) mm (P < 0.05). Adhesion test showed that the absorbance value in control, low, medium and high concentration groups were 1.14 ± 0.18, 0.95 ± 0.13, 0.81 ± 0.11 (P < 0.01), 0.67 ± 0.19 (P < 0.001). Comparisons between control and experimental groups were analyzed by t-test and P values < 0.05 were considered statistically significant. CONCLUSIONS: Zoledronic acid inhibits the proliferation, migration and adhesion of vascular endothelial cells.

Preparation and lithium storage performance of yolk-shell Si@void@C nanocomposites.

Yolk-shell Si@void@C nanocomposites are prepared via a facile method of resorcinol-formaldehyde coating and LiOH etching, without SiO2 pre-modification on Si particles, expensive carbon sources, or environmentally-unfriendly HF solutions. Profiting from these favorable features, Si@void@C nanocomposites exhibit considerable reversible capacities (628 mA h g(-1) after 100 cycles) and good rate performances.

Core double-shell Si@SiO2@C nanocomposites as anode materials for Li-ion batteries.

Core double-shell Si@SiO(2)@C nanocomposites were prepared through a facile route. SiO(2) and carbon double shells effectively accommodated the volume swing of Si during repeated cycles and enhanced the electronic network between nanoparticles.