Neuroimaging markers of early neurological deterioration in acute isolated pontine infarction.

BACKGROUND: Imaging indicators of early neurological deterioration (END) in patients with acute isolated pontine infarctions (AIPI) remained ambiguous. We aimed to find more specific neuroimaging markers for the development of END in patients with AIPI. METHODS: Patients with AIPI within 72 h of stroke onset were screened from a stroke database from January 2018 to July 2021 in the First Affiliated Hospital of Zhengzhou University. Clinical characteristics, laboratory tests, and imaging parameters were collected. The layers having the largest infarct area on diffusion-weighted imaging (DWI) and T2 sequences were chosen. On the transverse plane of DWI and sagittal plane of T2-Flair images, the maximum length (a, m) and maximum width (b, n) vertical to the length of the infarcted lesions were measured respectively. On the sagittal plane of T2-Flair image, the maximum ventrodorsal length (f) and rostrocaudal thickness (h) were measured. On the sagittal plane, lesions were evenly split into upper, middle, and lower types based on the lesion's location in the pons. The ventral and dorsal types of location were separated based on whether the ventral borders of the pons were involved on transvers plane. END was defined as a ≥2 point increase in the National Institutes of Health Stroke Scale (NIHSS) total score or a ≥1 point increase in the motor items within 72 h after admission. Multivariate logistic regression analyses were used to explore risk factors associated with END. The receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC) was performed to estimate the discriminative power and determine the optimal cut-off points of imaging parameters on the prediction of END. RESULTS: A total of 218 patients with AIPI were included in the final analysis. END occurred in 61 cases (28.0%). Multivariate logistic regression analysis showed that the ventral type of lesion location was associated with END in all models adjusted. In addition, in Model 1, b (odds ratio (OR) 1.145, 95% confidence interval (95% CI), 1.007-1.301) and n (OR 1.163, 95% CI 1.012-1.336); in Model 2, b*n (OR 1.010, 95% CI 1.002-1.018); in Model 3, n (OR 1.179, 95% CI, 1.028-1.353); and in Model 4, b (OR 1.143, 95% CI 1.006-1.298) and n (OR 1.167, 95% CI 1.016-1.341) were found to be associated with END respectively after different adjustments. ROC curve analysis with END showed that the AUC, the optimal cut-off value, and its sensitivity and specificity were 0.743 (0.671-0.815), 9.850 mm, and 68.9% and 79.0% for b; 0.724 (0.648-0.801), 10.800 mm, and 57.4% and 80.9% for n; and 0.772 (0.701-0.842), 108.274 mm2, and 62.3% and 85.4% for b*n, respectively (b*n vs b: P =0.213; b*n vs n: P =0.037; b vs n: P =0.645). CONCLUSIONS: Our study revealed that besides the ventral type of lesion location, the maximum width of lesion on the transverse plane of DWI and sagittal plane of T2 image (b, n) may be imaging markers for the development of END in AIPI patients, and the product of the two (b*n) showed a better prediction value on the risks of END.

Biomorphic CoNC/CoOx Composite Derived from Natural Chloroplasts as Efficient Electrocatalyst for Oxygen Reduction Reaction.

Natural chloroplasts containing big amounts of chlorophylls (magnesium porphyrin, Mg-Chl) are employed both as template and porphyrin source to synthesize biomorphic CoNC/CoOx composite as electrocatalyst for the oxygen reduction reaction (ORR). Cobalt-substituted chlorophyll derivative (Co-Chl) in chloroplasts is first obtained by successively rinsing in hydrochloric acid and cobalt acetate solutions. After calcining in nitrogen to 800 °C, Co-Chl is transferred to CoNC; while other parts of chloroplasts adsorbed with Co ions are transferred to CoOx retaining the microarchitecture of chloroplasts. The abundant active CoNC sites are protected by circumjacent biocarbon and CoOx to avoid leakage and agglomeration, and at the same time can overcome the poor conductivity weakness of CoOx by directly transporting electrons to the carbonaceous skeleton. This unique synergistic effect, together with efficient bioarchitecture, leads to good electrocatalytical performance for the ORR. The onset and half-wave potentials are 0.89 and 0.82 V versus reversible hydrogen electrode, respectively, with better durability and methanol tolerance than that of commercial Pt/C. Different from the traditional concept of biomorphic materials which simply utilize bioarchitectures, this work provides a new example of coupling bioderivative components with bioarchitectures into one integrated system to achieve good comprehensive performance for electrocatalysts.

Amorphous MnO2 on Carbon Substrate with Ordered Submicron Pore Array Structure for High Performance Supercapacitor Electrode.

MnO2/C composite with ordered submicron pore array structure was obtained by using Atrophaneura horishana butterfly wings as template and carbon source for high performance supercapacitor electrode. Micro/nanostructured carbon substrate was firstly constructed by calcining the wing specimen under nitrogen atmosphere. Then, amorphous MnO2 was formed on the structure via surface solution reaction. The as-prepared composite shows a high specific capacitance of 1342 F g-1 at 1 A g-1 with good rate capability and stability. The excellent charge-discharge performance should be attributed to the coupling effect of pseudocapacitive amorphous MnO2 and robust porous carbon. The pore array structured substrate not only provides high specific surface area for sufficient active sites, but also exhibits good connectivity for efficient charge and mass transport.

Lesion Indexes Predict Early Neurologic Deterioration in Lenticulostriate Single Small Subcortical Infarction.

BACKGROUND AND PURPOSE: Early neurologic deterioration (END) often occurs during hospitalization in single small subcortical infarction (SSSI). The objective was to identify imaging predictors of END. MATERIALS AND METHODS: SSSIs in the lenticulostriate artery within 72 hours of stroke onset from January 2015 to June 2021 were consecutively enrolled. The posteriority and laterality indexes were assessed on the second section from the top of the corona radiata section showing the lateral ventricle on DWI. A multivariate logistic analysis was used to explore the predictors of END. RESULTS: A total of 402 patients were included in this study, among whom 93 (23.1%) experienced END. The optimal cutoff points of the posteriority and laterality indexes for predicting END were given by a receiver operating characteristic curve. A multivariate logistic analysis showed that the posteriority index of ≥0.669 (OR: 2.53; 95% CI: 1.41-4.56; P = .002) and the laterality index of ≥0.950 (OR: 2.03; 95% CI: 1.03-4.00; P = .042) were independently associated with the risk of END. Accordingly, the SSSIs were further divided into 4 types: anterior lateral type (AL-type), anterior medial type (AM-type), posterior lateral type (PL-type), and posterior medial type (PM-type). After the multivariate analysis, in comparison with the AL-type, the AM-type (OR: 3.26; 95% CI: 1.10-9.65), PL-type (OR: 4.68; 95% CI: 1.41-15.56), and PM-type (OR: 6.77; 95% CI: 2.53-18.04) carried significantly elevated risks of END. The PM-type was associated with the highest risk of END. CONCLUSIONS: The PM-type was found to be associated with the highest risk of END.

Hollow CoSe2-ZnSe microspheres inserted in reduced graphene oxide serving as advanced anodes for sodium ion batteries.

Transition metal selenides are promising anode candidates for sodium ion batteries (SIBs) because of their higher theoretical capacity and conductivity than metal oxides. However, the disadvantages of severe capacity degradation and poor magnification performance greatly limit their commercial applications. Herein, we have developed a new hollow bimetallic selenides (CoSe2-ZnSe)@reduced graphene oxide (rGO) composite with abundant heterointerfaces. The rGO could not only alleviate the volume variations of hollow CoSe2-ZnSe microspheres during cycling, but also improve the conductivity of composite. The presence of the heterointerfaces could help to accelerate ionic diffusion kinetics and improve electron transfer, resulting in the improved sodium storage performance. As an advanced anode for SIBs, the CoSe2-ZnSe@rGO exhibits an enhanced initial coulombic efficiency of 75.1% (65.2% of CoSe2@rGO), extraordinary rate capability, and outstanding cycling stability (540.3 mAh/g at 0.2 A/g after 150 cycles, and 395.2 mAh/g at 1 A/g after 600 cycles). The electrochemical mechanism was also studied by kinetic analysis, showing that the charging/discharging process of CoSe2-ZnSe@rGO is mostly related to a capacitive-controlled behavior.

Clinical features and associated factors of coexisting intracerebral hemorrhage in patients with cerebral small vessel disease: a cross-sectional study.

Intracerebral hemorrhage (ICH) is generally considered to be closely related to cerebral small vessel disease (CSVD), leading to a poor prognosis. However, the coexistence of ICH in general CSVD patients and related factors remain underreported. In our cross-sectional study, we screened 414 CSVD patients from a database at the Department of Neurology, First Affiliated Hospital of Zhengzhou University (September 2018 to April 2022). Imaging biomarkers of CSVD and coexisting ICH lesion were assessed. Factors associated with coexisting ICH in CSVD were determined using multivariate logistic regression analysis. ICH was observed in 59 patients (14.3%). Multivariate logistic regression showed that previous history of ischemic stroke or transient ischemic attack (OR 5.189, 95%CI 2.572-10.467, P < 0.001), high-grade perivascular space in the basal ganglia (n > 10) (OR 2.051, 95%CI 1.044-4.027, P = 0.037) and low adjusted calcium-phosphorus product (OR 0.728 per 1 [mmol/L]2 increase, 95%CI 0.531-0.998, P = 0.049) were associated with coexisting ICH in CSVD patients. The considerable proportion of coexisting ICH and revelation of associated factors in general CSVD patients alert physicians of the potential risk of the reoccurrence of ICH, and might have a significant impact on therapeutic strategies.

Heterogeneous bimetallic selenides encapsulated within graphene aerogel as advanced anodes for sodium ion batteries.

Metal selenides are promising anode candidates for sodium ion batteries (SIBs) because of their high theoretical capacity, low cost, and environmental friendship. However, the low rate capability at high current density due to its inherent low electrical conductivity and poor cycle stability caused by inevitable volume variations during cycling frustrate its practical applications. Herein, we have developed a simple metallic-organic frameworks (MOFs)-derived selenide strategy to synthesize a series of heterogeneous bimetallic selenides encapsulated within graphene aerogels (GA) as anodes for SIBs. The bimetallic selenides/GA composites have unique structural characteristics that can shorten the migration path for Na+/electrons and accommodate the volume variations via additional void space during cycling. The built-in electric fields induced at the heterointerfaces can greatly reduce the activation energy for rapid charge transfer kinetics and promote the diffusion of Na+/electrons. GA is also beneficial for accommodating the volume variations during cycling and improving conductivity. As an advanced anode for SIBs, the MoSe2-Cu1.82Se@GA with a special porous octahedron can deliver the highest capacity of 444.8 mAh/g at a high rate of 1 A/g even after 1000 cycles among the bimetallic selenides/GA composites.

Synthesis and characterization of core-shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 cathode for high-performance lithium ion batteries.

High-nickel cobalt-free layered cathode is regarded as a highly potential cathode material for the next generation lithium ion batteries (LIBs) because of its high energy density, low cost and environmentally benign. However, the poor cycle performance caused by its intrinsic unstable structure and chemo-mechanical instability frustrates its practical applications. Herein, we have developed a new core-shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 (LZO-NMA9523) cathode for high-performance LIBs. The Li2ZrO3 coating layer firstly helps to suppress and reduce the degree of Li+/Ni2+ cation mixing during the material preparation process. In addition, the Li2ZrO3 coating layer can not only accommodate the volume variations and enhance the electricity of the active materials, but also effectively inhibit the harmful irreversible phase transition during the charging/discharging process, thus greatly stabilizing the structure of the high-nickel cobalt-free cathode. As an advanced cathode for LIBs, the LZO-NMA9523 exhibits an excellent reversible capacity of 146.9 mAh g-1 after 100 cycles at 0.5 C with capacity retention of about 80%. This study provides a possible high-nickel cobalt-free layered cathode material for the next generation LIBs.

[Isoprenylated phenolic compounds from leaves of Morus yunnanensis].

Phytochemical investigation on an EtOH extract of the leaves of Mons yunnanensis led to the isolation and characterization of 11 isoprenylated phenolic compounds, morusyunnansin G (1), morachalcone B (2), cudraxanthone M (3), cudraxanthone D (4), sanggenofuran B(5), moracin D (6), moracin C (7), moracin I (8), demethylmoracin I (9), morachalcone A (10), and isobacachalcone (11). Compound 1 is a new compound and compounds 2-11 were isolated from this plant for the first time.

Stress hyperglycemia predicts early neurological deterioration and poor outcomes in patients with single subcortical infarct.

AIM: The goal of this study was to determine whether the stress hyperglycemia ratio (SHR) is associated with early neurological deterioration (END) and poor outcomes in patients with single subcortical infarct (SSI). METHODS: For this study, we prospectively enrolled patients with SSI admitted between 2015 and 2021. SHR was distributed in quartiles according to the size of each subgroup. END was defined as an increase of ≥ 2 total points in the National Institutes of Health Stroke Scale (NIHSS) or ≥ 1 point in the motor items of the NIHSS within 7 days of hospital admission. The modified Rankin Scale (mRS) was used to evaluate patient prognosis. Good and poor outcomes were defined as mRS scores ≤2 and >2, respectively. The relationships between SHR and risk of END as well as outcomes were analyzed using multivariate logistic regression models. RESULTS: A total of 1049 patients with SSI with an average age of 59.49 years met the inclusion criteria for the analysis. The incidence of END markedly increased with increasing SHR. Multivariate logistic regression analysis revealed that the highest SHR quartile was independently associated with an increased risk of both END (OR 4.04, 95% CI, 2.43-6.69, P < 0.001) and 3-month poor outcomes (OR 2.34, 95% CI, 1.44-3.82, P = 0.001), compared to the lowest quartile. A receiver operating characteristic curve analysis of the SHR based on the area under the curve showed a diagnostic accuracy equal or greater than fasting plasma glucose. CONCLUSION: SHR is a reliable predictor of END and poor outcomes in patients with SSI.

Early neurological deterioration in patients with acute ischemic stroke: a prospective multicenter cohort study.

Background: There is still no precise knowledge of the causes of progression in patients with acute ischemic stroke (AIS), and we are unable to predict patients at risk. Objective: To explore the frequency, predictive factors, and the prognosis of early neurological deterioration (END) in patients with AIS. Methods: In this prospective multicenter observational study, we assessed patients with AIS admitted to 18 hospitals in Henan, China. We defined END as an increase of ⩾2 points in total National Institutes of Health Stroke Scale (NIHSS) score or ⩾1 point in the motor items of the NIHSS within 7 days after admission. Risk factors were analyzed using multivariate logistic regression models. Prognosis was evaluated using the modified Rankin Scale (mRS), with poor prognosis defined as mRS 3-6. Results: A total of 9114 patients with AIS within 24 h of symptom onset were enrolled in the study. END occurred in 1286 (14.1%) patients. The highest incidence (62.5%) of END occurred within 24 h after admission. After adjusting potential confounders, age, body mass index, waist-hip ratio, systolic blood pressure, baseline NIHSS, disabled at baseline, history of atrial fibrillation, diabetes mellitus, intracranial arterial stenosis, infarct location in the lenticulostriate artery area and cerebral watershed, neutrophils, lymphocytes, uric acid, and triglycerides were identified as independent predictors for END. END was significantly associated with poor prognosis at 90 days, and the adjusted OR was 1.74 (95% CI: 1.53-1.97). Conclusion: One in seven hospitalized patients with AIS may experience END within 24 h of onset. The highest incidence of END occurred within 24 h of admission and decreased steeply with time. Easily identifiable risk factors predict END and could help understand the causal mechanisms and thereby prevent END.

New isoprenylated flavones and stilbene derivative from Artocarpus hypargyreus.

Three new isoprenylated flavones, hypargyflavones A-C (1-3, resp.), and one novel stilbene derivative, hypargystilbene A (4), together with seven known compounds, 5-11, were isolated from the stems of Artocarpus hypargyreus Hance. The structures were elucidated by spectroscopic methods. Hypargyflavone A (1), cudraflavone C (8), brosimone I (10), and norartocarpin (11) showed inhibitory effects on pancreatic lipase.

A Low-Cost SiO x /C@Graphite Composite Derived from Oat Husk as an Advanced Anode for High-Performance Lithium-Ion Batteries.

Silicon monoxide (SiO x ), as a promising anode for the next-generation high-power lithium-ion batteries, has some advantages such as higher lithium storage capacity (∼2400 mAh g-1), suitable working potential, and smaller volume variations during cycling compared with pure silicon. However, its disadvantages such as its inherent low conductivity and high cost impede its extensive applications. Herein, we have developed a low-cost and high-capacity SiO x /C@graphite (SCG) composite derived from oat husks by a simple argon/hydrogen reduction method. For further practical application, we also investigated the electrochemical performances of SiO x mixed with different ratios of graphite. As an advanced anode for lithium-ion batteries, the SCG-1 composite exhibits an excellent electrochemical performance in terms of lithium storage capacity (809.5 mAh g-1 at 0.5 A g-1 even after the 250th cycle) and high rate capability (479.7 mAh g-1 at 1 A g-1 after the 200th cycle). This work may pave the way for developing a low-cost silicon-based anode derived from biomass with a large reversible capacity and long cycle life in lithium-ion batteries.

Efficacy and Safety of Alteplase on Treatment of Acute Single Small Subcortical Infarction.

BACKGROUND: Single Small Subcortical Infarction (SSSI) is an isolated small infarction in the territory of perforating artery with a maximum diameter of 20 mm in axial Diffusion-Weighted Imaging (DWI). About 20 to 30% of SSSI patients were reported to have Early Neurological Deterioration (END) in the acute phase, which brought adverse effects on long-term outcomes. The effect of the alteplase on the outcome of SSSI, especially END and long-term outcomes, was ambiguous. OBJECTIVE: The study aims to find out the efficacy and safety of intravenous recombinant tissue Plasminogen Activator (rt-PA) on long-term and short- outcomes of patients with SSSI as compared to patients who received standard medical care. METHODS: The patients were retrospectively screened from a stroke registry of the neurology department of 1st Affiliated Hospital of Zhengzhou University from January 2013 to December 2020. Based on treatment modality, patients were dichotomized into alteplase and standard medical care groups. To minimize confounding factors in subgroups, a propensity score matching analysis was done. The primary outcome was the favorable functional outcome 3 months after stroke onset, defined by attaining a score of ≤2 points on the modified Rankin scale (mRS), secondary outcome was the prevention of occurrence of END, defined as an increase of ≥2 points in the total score or ≥1point on motor subunit in the National Institutes of Health Stroke Scale (NIHSS) score within 72 hours after admission, safety features were symptomatic intracranial hemorrhage (sICH) or death. Multivariate analysis was employed to find the efficacy and safety of alteplase in the treatment of SSSI. RESULTS: A total of 717 patients with anterior circulation SSSI were selected, and 132 were included in the final analysis. Forty-five patients were treated with alteplase within 4.5 hours and 87 with standard medical care, and 44 pairs were successfully matched by propensity score. Pre-match data showed that the alteplase thrombolysis group showed a higher proportion of favorable outcomes at 3-month follow-up [OR=0.315, 95%CI:0.106, 0.931, P = 0.037] but did not reduce the incidence of END compared with the non-thrombolytic group [OR = 1.033, 95%CI:0.417,2.554, P = 0.943]. Post-match data showed that the alteplase group also showed a higher proportion of favorable outcomes at 3-month follow-up [OR = 0.247, 95%CI: 0.074, 0.830, P = 0.024]; however, it did not reduce the incidence of END compared with the non-thrombolytic group [OR = 1.241, 95%CI: 0.433,3.554, P = 0.688]. There was one case of asymptomatic ICH in alteplase treated patients. CONCLUSION: Patients with SSSI in the anterior circulation are more likely to achieve 3 months favorable outcomes than those who were treated with standard medical care; however, treatment with alteplase may not prevent the occurrence of END.

Prediction of Symptoms on Admission with Early Neurological Deterioration in Single Small Subcortical Infarct.

BACKGROUND: Early neurological deterioration (END) often occurs during hospitalization in single small subcortical infarct (SSSI). While, symptoms on admission were rarely reported about its performance on predicting the risk of END. OBJECTIVES: The objective of this study is to explore the relationship between symptoms on admission and END in SSSI. METHODS: Patients with SSSI in the lenticulostriate artery (LSA) territory presenting within 72 hours of stroke onset were screened prospectively. Clinical characteristics, including symptoms on admission, laboratory tests and imaging findings, were collected. Based on the body regions involved including spherical face (SF), upper limb (UL) or lower limb (LL), symptoms on admission were classified into single spherical face (sSF) and any involvement of limbs (AL). END was defined as ≥2 points increase in total National Institutes of Health Stroke Scale (NIHSS) score or ≥ 1 point increase in motor score within 72 hours after admission. Multivariate logistic regression was used to analyze factors associated with END. RESULTS: Out of 5,832 ischemic stroke patients in the database, 394 patients were finally enrolled in analysis. 65 patients (16.5%) developed END. Multivariable logistic regression revealed that symptoms with LL (OR 2.337, 95% CI 1.041-5.246), UL (OR 2.936, 95% CI 1.349-6.390) were both associated with END, while the involvement of SF (OR 0.447, 95% CI 0.249-0.804) showed the opposite result. Further analysis found that symptoms with AL (OR 3.958, 95% CI 1.355-11.565) showed a higher risk of END compared to sSF after adjustment. CONCLUSION: Our results discovered that symptoms with AL carried a higher risk of END than those involving sSF in SSSI.

Lesion Location Predicts Early Neurological Deterioration in Single Subcortical Infarction.

BACKGROUND: A certain number of patients with single subcortical small infarction (SSSI) in the lenticulostriate artery (LSA) territory present with early neurological deterioration (END). OBJECTIVE: We sought to identify a more specific predicting imaging marker for END in lenticulostriate SSSI patients. METHODS: We screened patients in a prospective hospital-based registry of stroke in the first Affiliated Hospital of Zhengzhou University from January 2015 to December 2020. Lesion locations were defined as posterior type when more than half of the lesion was located in the posterior part of the corona radiata divided by the midline, which was drawn between the tangents of the anterior and posterior horns of the lateral ventricle and was adjacent to the lateral ventricle at the same time. END was defined as an increase of ≥2 points in total National Institutes of Health Stroke Scale score or ≥1 point. A multivariate logistic analysis was used to assess the imaging predictors for END. RESULTS: 418 patients were enrolled in the final data analysis. Among them, 206 (49. 3%) cases were rated as the posterior type and71 (17.0%) cases had to END. A multivariate logistic analysis showed that only the posterior type (adjusted odds ratio, 2. 126; 95% confidence interval, 1. 250-3. 614; P = 0. 005) was independently associated with the risk of END. CONCLUSION: The posterior type of lesion location represented an imaging marker predicting END in lenticulostriate SSSI patients.

pH-Dependent syntheses and crystal structures of a series of organic-inorganic hybrids constructed from Keggin or Wells-Dawson polyoxometalates and silver coordination compounds.

A series of silver complexes of polyoxometalates (POMs), formulated as, [Ag(2)(4,4'-bpy)(2)(4,4'-Hbpy)(H(2)O)][PW(12)O(40)] (4,4'-bpy = 4,4'-bipyridine, 1), [Ag(4)(4,4'-bpy)(4)][4,4'-H(2)bpy][P(2)W(18)O(62)].4H(2)O (2), [Ag(4)(4,4'-bpy)(4)][H(2)P(2)W(18)O(62)].7H(2)O (3), and Na(8)[Ag(3)(4,4'-bpy)(3)][PW(10)Ag(2)O(39)].6H(2)O (4), have been hydrothermally synthesized in situ at different pH. Complex 1, based on saturated Keggin POM building blocks and silver coordination compounds, exhibits an interesting 3-fold interpenetration of diamondlike network in the POM chemistry. Different from complex 1, complexes 2-3 consist of Wells-Dawson polyoxoanions and silver coordination compounds. Complex 2 represents the highest coordination number of Wells-Dawson polyoxoanions, which helps to form a high-dimensional framework with (4.6(4).8)(4)(4(4).6(16).8(8)) topology. Thee-dimensional (3D) Wells-Dawson phosphotungstate 3 reveals another new topology (4.6(4).7)(4.6(4).8)(2)(4(3).6(8).7(2).8(2)). Complex 4 forms a 3D framework constructed from divacant Keggin polyoxoanions and silver coordination compounds. Their structural differences indicate that the pH value of the reaction system plays a key role on the structures and topologies of these complexes, and the whole self-assembly process is pH-dependent.

A Low-Cost and High-Capacity SiO x /C@graphite Hybrid as an Advanced Anode for High-Power Lithium-Ion Batteries.

Silicon suboxide (SiO x ) is one of the most promising anodes for the next-generation high-power lithium-ion batteries because of its higher lithium storage capacity than current commercial graphite, relatively smaller volume variations than pure silicon, and appropriate working potential. However, the high cost, poor cycling stability, and rate capability hampered its industrial applications due to its complex production process, volume changes during Li+ insertion/extraction, and low conductivity. Herein, a low-cost and high-capacity SiO x /C@graphite (SCG) hybrid was designed and synthesized by a facile one-pot carbonization/hydrogen reduction process of the rice husk and graphite. As an advanced anode for lithium-ion batteries, the SiO x /C@graphite hybrid delivers a high reversible capacity with significantly enhanced cycling stability (842 mAh g-1 after 300 cycles at 0.5 A g-1) and rate capability (562 mAh g-1 after 300 cycles at 1 A g-1). The great improvement in performances could be attributed to the positive synergistic effect of SiO x nanoparticles as lithium storage active materials, the in situ-formed carbon matrix network derived from biomass functioning as an efficient three-dimensional conductive network and spacer to improve the rate capability and buffer the volume changes, and graphite as a conductor to further improve the rate capabilities and cycling stability by increasing the conductivity. The low-cost and high-capacity SCG derived from rice husk synthesized by a facile, scalable synthetic method turns out to be a promising anode for the next-generation high-power lithium-ion batteries.

Dual-Templating Approaches to Soybeans Milk-Derived Hierarchically Porous Heteroatom-Doped Carbon Materials for Lithium-Ion Batteries.

Biomass derived carbon materials are widely available, cheap and abundant resources. The application of these materials as electrodes for rechargeable batteries shows great promise. To further explore their applications in energy storage fields, the structural design of these materials has been investigated. Hierarchical porous heteroatom-doped carbon materials (HPHCs) with open three-dimensional (3D) nanostructure have been considered as highly efficient energy storage materials. In this work, biomass soybean milk is chosen as the precursor to construct N, O co-doped interconnected 3D porous carbon framework via two approaches by using soluble salts (NaCl/Na2CO3 and ZnCl2/Mg5(OH)2(CO3)4, respectively) as hard templates. The electrochemical results reveal that these structures were able to provide a stable cycling performance (710 mAh ⋅ g-1 at 0.1 A ⋅ g-1 after 300 cycles for HPHC-a, and 610 mAh ⋅ g-1 at 0.1 A ⋅ g-1 after 200 cycles for HPHC-b) in Li-ion battery and Na-ion storage (210 mAh ⋅ g-1 at 0.1 A ⋅ g-1 after 900 cycles for HPHC-a) as anodes materials, respectively. Further comparative studies showed that these improvements in HPHC-a performance were mainly due to the honeycomb-like structure containing graphene-like nanosheets and high nitrogen content in the porous structures. This work provides new approaches for the preparation of hierarchically structured heteroatom-doped carbon materials by pyrolysis of other biomass precursors and promotes the applications of carbon materials in energy storage fields.

Facile in situ fabrication of biomorphic Co2P-Co3O4/rGO/C as an efficient electrocatalyst for the oxygen reduction reaction.

Streptococcus thermophilus, a Gram-positive (G+) bacterium featuring a teichoic acid-rich cell wall, has been employed as both a phosphorus source and template to synthesize a biomorphic Co2P-Co3O4/rGO/C composite as an efficient electrocatalyst for the oxygen reduction reaction (ORR). Different from the conventional method for the synthesis of phosphides, bio-derivative phosphorus vapor was emitted from the inside out, which facilitated the in situ transformation of the chemically adsorbed Co precursor on the bacteria into Co2P-Co3O4 heterogeneous nanoparticles, which featured a Co2P-rich body and Co3O4-rich surface. Besides, reduced graphene oxide (rGO) was also introduced in the synthetic process to keep Co2P-Co3O4 scattered and further promote the electron transport efficiency. All the Co2P-Co3O4 nanoparticles and rGO sheets were supported on the bacteria-derived carbon substrate with submicron-spherical morphology. The as-obtained Co2P-Co3O4/rGO/C composite exhibited excellent electrocatalytic performance for ORR with onset and half-wave potentials of 0.91 and 0.80 V vs. RHE, respectively. Furthermore, its long-term stability and methanol tolerance were better than those of commercial Pt/C. Thus, this work presents a new strategy of using an interior bio-phosphorus source to obtain heterojunction particles featuring a phosphide-rich body and oxide-rich surface, which may provide some insights for the construction of efficient heterogeneous electrocatalysts.