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Sodium ascorbate aqueous solution as the washing solution for the preparation of Prussian blue can inhibit the loss of Na+ and the oxidation of Fe2+, so as to achieve excellent electrochemical sodium storage performance.

Hydrogen (H2) produced by photocatalytic water splitting on semiconductor is a prospective way to make full use of solar energy. Here, we synthesized a composite consisting of P25 nanoparticles combined with open hollow sphere cuprous oxide (Cu2O) through a simple one-pot hydrothermal method. Cu2O/TiO2 (P25) (60 wt%, labeled as CP-60) exhibited the highest H2 evolution rate as high as 2.55 mmol g−1 h−1, which was 41.46 and 3.88 folds higher than pure Cu2O and P25. The improvement of photocatalytic H2 performance is mainly due to the formation of Cu2O/TiO2 (P25) p–n heterojunction, which effectively separates the electron hole pairs (e−–h+) and improves the charge transfer rate of the materials. Meanwhile, the excellent H2 production performance is also attributed to the effective use of sunlight under the synergistic effect of visible light and ultraviolet light. This work presents a simple and feasible method to enhance the activity and stability of Cu2O photocatalytic H2 production.

The detection of volatile organic gas triethylamine (TEA) is of great significance to environment quality and human health. However, it is still a challenge to achieve high-sensitivity detection at low temperatures. In this work, a TEA sensor with a low operating temperature and high response was successfully prepared by designing ZnO/SnO2 composite material rich in oxygen vacancy defects. A camellia-like ZnO material was synthesized by a hydrothermal method using surfactant, bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT) as a soft template. SnO2 nanoparticles with a diameter of 20 nm were dispersed on ZnO nanosheets to form a ZnO/SnO2 heterostructure. The sensor based on ZnO/SnO2-10 demonstrates an extremely high response of 780 to 100 ppm TEA. More importantly, the response value of 1 ppm TEA detected is 6 and the detection limit is as low as 0.43 ppm. Besides, the sensor has a low working temperature of 100 °C. The enhancement of TEA sensing performance could be attributed to the synergistic effect of oxygen vacancy (Vo), ZnO–SnO2 heterojunction, and the ZnO (001) exposure plane. Vo can be used as the active center of oxygen molecule adsorption to produce highly active O2− species. Furthermore, Vo–ZnO has higher adsorption energy for TEA molecules than pure ZnO, which was determined using first-principles calculations, confirming the strong interaction between Vo–ZnO and TEA. The sensor shows a broad application prospect in food safety detection and environmental monitoring.

Gas sensors based on metal oxides semiconductor (MOS) have attracted extensive attention from both academic and industry. ZnO, as a typical MOS, exhibits potential applications in toxic gas detection, owning to its wide band gap, n-type transport characteristic and excellent electrical performance. Meanwhile, doping is an effective way to improve the sensing performance of ZnO materials. In this review, the effects of different types of doping on morphology, crystal structure, band gap and depletion layer of ZnO materials are comprehensively discussed. Theoretical analysis on the strategies for enhancing the sensing properties of ZnO is also provided. This review puts forward the reasonable insight for designing efficient n-type ZnO-based semiconductor oxide sensing materials.

Background Pineal region glioma is a rare systematically reported tumor in the literatures, and little is known about its behavior, development, and best treatment strategies because of its complex anatomical relationship and rarity. Objective We reviewed the outcomes of patients with pineal region gliomas in West China hospital in the past 5 years and searched the literature to add more information. As a result, key factors related to prognosis are identified. Methods Twenty-five patients with pineal region gliomas were selected and information was collected about detailed medical history, imaging data, treatment methods, pathologic results, and latest neurosurgical radiologic progress during follow-up. Results Pilocytic astrocytomas (20%) and glioblastomas (24%) were the most common pathologic subtypes. Twenty-three patients underwent open surgery, 3 Gamma Knife radiosurgery, and 4 whole-brain radiation therapy. Chemotherapy was applied to 3 patients. Low-grade gliomas tended to have a better prognosis than did high-grade. Karnofsky Performance Status at admission (≤60) was intimately associated with prognosis for low-grade gliomas. As for high-grade gliomas, patients whose age at admission was ≤30 years had a better prognosis than did older patients (＞30 years). However, whatever the grade, there was no overall survival difference as to gender, gross total resection versus not gross total resection, preoperative maximal tumor diameter (≤4 vs. ＞4 cm), and time since first symptoms (≤30 vs. ＞30 days), and radiation therapy versus no radiation therapy. Conclusions Open surgery is the first-line strategy for pineal region gliomas with tolerable mortality and disability rate. Radiosurgery and chemotherapy can be applied as adjuvant or alternative methods when surgery is contraindicated.

Three-dimensional nano-mulberries consisting of SnO2 nanoparticles have been successfully anchored onto the surfaces of reduced graphene oxide (RGO) to construct hierarchical hybrids—SnO2@RGO with a one-pot approach. The SnO2 nano-mulberries with different amounts of RGO have been produced for optimizing their composition effect on Li storage performance. Specifically, SnO2@RGO hybrids incorporated with optimized amount of RGO nanosheets (∼20.8%) exhibit highly enhanced capacity of ∼1025 mA h/g at 0.1 A/g and a reversible capacity of 750 mA h/g over 100 cycles at 0.2 A/g. The materials also deliver much better rate performance with average specific capacity of ∼498 mA h/g at 2 A/g in comparison with that of SnO2 nano-mulberries. After cycling for 600 times at 1 A/g, the SnO2@RGO electrodes still maintain high reversible capacity of ∼602 mA h/g, corresponding to 35% of the second cycle and 133% of the 70th discharge capacity.

The effect of reduced graphene oxide coating on the electrochemical performance of monodispersed core–shell MoS2 spheres has been presented. The 3D nanoarchitectures constructed with 2D MoS2 and RGO nanosheets can be applied to assemble anodes with highly enhanced capacity in storing lithium. The amount of reduced graphene oxide nanosheets can dramatically affect the electrochemical properties of as-prepared 3D nanoarchitectures. Specifically, the MoS2 anode materials with ~ 7 wt% of reduced graphene oxide exhibit the highest average specific capacity of ~ 1134 mAh g−1 at 100 mA g−1, and it recovers up to 89.2% after performing discharge–charge at 2000 mA g−1. The discharge capacity of the electrode can retain ~ 88.9% of its second discharge capacity after cycling for 100 times at 200 mA g−1 and keep ~ 98.3% of its average Coulombic efficiency after the first cycle. The cells also possess high rate with specific capacity of ~ 739 mAh g−1 even at 1000 mA g−1.

After synthesized with a solvothermal process, LiFePO4 nanoparticles have been further modified with reduced graphene oxide (rGO) and Ag nanoparticles via a facile heat treatment route. The as-prepared LiFePO4@rGO/Ag exhibits enhanced electrochemical performance in storing Li ions with more than 60% increase in discharge specific capacity compared with pristine LiFePO4 at C/10. The discharge specific capacity of the as-prepared cathode materials reaches to 130 mAhg−1 at high rate of 5 C, which is about 4 times higher than that of pristine LiFePO4. The highly enhanced electrochemical properties of the cathode materials can be attributed to the synergetic effect of rGO nanosheets and Ag nanoparticles, which can build up conductive networks to form 3D nanocomposites together with LiFePO4.

Objective: Anterior capsulotomy (AC) is sometimes used as a life-saving treatment for patients with treatment-refractory obsessive-compulsive disorder (Tr-OCD). Most of the previous studies have assessed only total symptoms and have concluded that AC is a safe and effective procedure. Few of these studies have focused on meticulously investigating the variety of results obtained from patients with different subtypes of OCD. This study reviewed the long-term effects of AC on patients with OCD and analyzed the dissimilarity between particular subtypes of the disease in order to determine which groups are more suited to surgical treatment. Methods: For this retrospective evaluation, we selected 54 consecutive patients from a total of 63 people with Tr-OCD between 2005 and 2014 who had undergone AC by thermocoagulation at our department. Preoperative and follow-up assessments were conducted at multiple time points (before surgery and 1, 3, 6, 12, and 36 months after surgery). The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) were used to quantify the symptoms of OCD. According to different elements (clinical manifestation, comorbidity, and whether a patient was more compulsive or more obsessive), we classified patients into various subtypes and analyzed the variation in symptom improvement and adverse effects. Results: The mean Y-BOCS, HAMD, and HAMA scores were, respectively, 27.03, 23.30, and 21.46 preoperatively and 8.50, 7.07, and 7.42, respectively, at 36 months after surgery. Most patients (n = 43, 79.6%) were shown to have been at least partially responsive to surgical treatment at their long-term follow-up. Six patients demonstrated no obvious improvement (Y-BOCS score decreased by Conclusions: AC is effective in reducing symptoms of OCD. By comparing differently classified follow-up results, we found that patients with most subtypes/dimensions of OCD showed good outcomes. How­ever, patients categorized into the OCD subtypes of pure ­obsessive thoughts, symmetry/ordering, hoarding, OCD with obsessive slowness, and OCD comorbid with psychiatric symptoms should take into account these results before undergoing AC.

Ultrathin HNb3O8 nanosheets (HNb3O8 NSs) with oxygen vacancies were successfully synthesized by a simple bottom-up hydrothermal process. The obtained nanosheets were uniform with a thickness of about 3.02 nm and the surface oxygen vacancies on the HNb3O8 nanosheets were confirmed by electron spin resonance spectroscopy (ESR) and X-ray photoelectron spectroscopy (XPS). As compared to urchin-like Nb2O5 nanospheres and Nb2O5 nanorods, ultrathin HNb3O8 nanosheets with oxygen vacancies showed higher activities in the photocatalytic oxidative coupling reaction of benzylamine under visible light irradiation. The improved photocatalytic activity of HNb3O8 NSs was attributed to the following: (1) unique nanosheet structure with different molecular thicknesses that led to the effective separation of the photogenerated carriers; (2) a benzylamine-HNb3O8 surface complex formed on the oxygen vacancies, which reduced the bandgap of HNb3O8 NSs and was beneficial to harvest visible light; (3) HNb3O8 NS-V could efficiently chemisorb O2 molecules and promote the activation of O2 to reactive oxygen species.

Double-platelet, single-platelet and spherical ZnO microcrystals were fabricated via a facile and controllable hydrothermal method. The morphology of the ZnO microcrystals and the exposure ratio of the (001) crystal surface were regulated by adjusting the pH of the solution. The ZnO microcrystals were modified with Pd nanoparticle loading by simple calcining, and the interaction of Pd nanoparticles (NPs) on the ZnO crystal surface increased its oxygen vacancy content. A micro-amount (0.05 wt%) of Pd NP-doped ZnO double-platelets (D-ZnO-0.05) enhanced the gas sensing of the sensor to 3.5 times that of pure double-platelet ZnO. The gas sensing results indicate that D-ZnO-0.05 exhibits a high response (71.2 for NO2 with 25 ppm), fast response/recovery (25 s/21 s), and superior long-term stability (remained at around 95.5% after 35 days). The enhancement in the gas sensing could be attributed to the catalysis of Pd NPs and the increase in the number of oxygen vacancies as a result of Pd loading. The band structure of D-ZnO-0.05 could be effectively tuned by introducing Pd nanoparticles, as shown in density functional theory (DFT) calculations. The Pd dopant and oxygen vacancies reduce the band gap of the ZnO(001) crystal materials, resulting in excellent sensor performance. It is believed that the D-ZnO-0.05 microcrystals could provide inspiration for crystal growth studies and high NO2 gas sensing.

Hierarchical microflowers architecture assembled with 2D porous ZnO nanosheets were fabricated by a one-step solvothermal method and subsequent annealing process. A series of Pd ZnO have been produced by injecting various volumes of Pd(NO3)2·2H2O solution. The ZnO and Pd ZnO microflowers are applied to fabricate gas sensors to investigate their sensing characteristics for various gases at different operating temperatures. The 0.05 wt% Pd ZnO exhibit the highest selective enhancement of acetone (165%) than ammonia (0.9%), methanal (38%), methanol (71%), H2 (35%) and CO (15%). In addition, it possesses the lower operating temperature and shorter response/recovery times (11s, 5s) toward acetone gas compared with the pure ZnO microflowers.

Enabling stable lithium metal anodes is significant for developing electrochemical energy storage systems with higher energy density. However, safety hazards, infinite volume expansion, and low coulombic efficiency (CE) of lithium metal anodes always hinder their practical application. Herein, a nano-thickness lithiophilic Cu-Ni bimetallic coating was synthesized to prepare dendrite-free lithium metal anodes. The electron cloud migration effect caused by the different electronegativities of Cu and Ni can achieve lithiophobicity/lithiophilicity transformation and thus promote uniform Li deposition/dissolution. By changing the ratio of Cu to Ni, the electron cloud migration can be reasonably adjusted for obtaining dendrite-free lithium anodes. As a result, the as-obtained Cu-Ni bimetallic coating is able to guarantee dendrite-free lithium metal anodes with a stable long cycling time (>1500 hours) and a small voltage hysteresis (∼26 mV). In addition, full cells with LiFePO4 as a cathode present excellent cycling stability and high coulombic efficiency. This work can open a new avenue for optimizing the lithiophilicity of materials and realizing dendrite-free anodes.

The Cu2O/TiO2 heterogeneous materials were fabricated via simple hydrothermal and physical mixing processes to investigate the photocatalytic H2 production performance. The morphology evolution of Cu2O was systematically explored by adjusting the amount of chemical reagents. The CT-70 (the additive amount of TiO2 was 70 wt%) exhibited superior photocatalytic activity with H2 production of 8.33 mmol g−1 in 6 h, which was about 416 and 49-fold more elevated those of Cu2O and TiO2. The enhancement of H2 generation was ascribed to the proper band gap structure and the heterojunction between Cu2O and TiO2. This work provides a strategy for the simple preparation of composite materials with high photocatalytic activity.

We have realized the selective detections of acetone and H2S vapors through tailoring the surface microstructures of ZnO crystals. Specifically, ZnO prisms mainly incased in equivalent [1 0 0] facets exhibit the highest response to H2S, and ZnO twin-spheres exposed in ±(0 0 1) facets show selective response to acetone. In comparison, the ZnO dumbbells exposed both in ±(0 0 1) and equivalent [1 0 0] facets respond to acetone and H2S similarly. The selective responses of the sensors are closely related to the adsorption energies (Ea) of the chemicals to the special facets of ZnO supercrystals, based on the first-principles calculations. The ±(0 0 1) and equivalent [1 0 0] facets of the ZnO crystals prefer to absorb acetone and H2S, respectively, which offer a chance of selectively sensing the chemicals.

Core–shell Cu2O@ZnO composites were synthesized successfully based on a one-pot hydrothermal method in the presence of dioctyl sulfosuccinate sodium salt (AOT) surfactant. The Cu2O can be converted to rough core–shell Cu2O@ZnO structure by adjusting the amount of zinc powder added. The as-synthesized Cu2O@ZnO composites exhibited excellent photocatalytic activity and the amount of H2 generated using these composites was 4.5-fold more than that produced with Cu2O cubes. A possible photocatalytic mechanism for the Cu2O@ZnO composites with enhanced photocatalytic activity could be the separation by ZnO of the effective charge carriers.

Ag@LiFePO4 cathode materials have been prepared successfully by performing solid-state reactions between AgNO3 and the ascorbic acid in the presence of LiFePO4 powders at ambient temperature. Metallic Ag nanoparticles of ca. 10 nm in diameter can be produced with the environmental benign approach and efficiently attached onto the surfaces of commercial LiFePO4 cathode materials. The as-prepared composites show highly enhanced electrochemical performances in storing Li with ca. 22% increase in their discharge specific capacity from 128 to 156 mAhg−1 at C/10 rate, after loading Ag additive of 2 wt%. The coulombic efficiency of the composites can retain 97%, after cycling for 80 times. They can also remain up to 94 mAhg−1 of their discharge specific capacity at high rate of 5 C, which is almost twice higher than that of LiFePO4 cathode materials.

Background Microvascular decompression (MVD) and Gamma Knife surgery (GKS) are the primary treatments for trigeminal neuralgia (TN). However, many patients require further surgical treatment after initial surgery for recurrent TN. The aim of this study was to evaluate efficacy and safety of GKS for recurrent TN cases with prior MVD. Methods From October 2008 to June 2015, 658 patients at West China Hospital underwent GKS as the only surgical treatment, and 42 patients underwent GKS with prior MVD. The single 4-mm isocenter was located at the cisternal portion of the trigeminal nerve in all patients. Median maximum prescription dose was 85 Gy (range, 70–90 Gy). Results Median follow-up time was 6.2 years (range, 1.1–10 years). The percentage of patients with or without previous MVD within 1 year was 56.81%, and the percentage of patients who were pain-free was 74.74%. The recurrence rates within 10 years were 49.11% and 43.74% for patients with and without MVD, respectively. Also, 9.52% and 11.04% of patients with and without previous MVD experienced complications as a result of GKS during the long-term follow-up period. Patients who underwent previous MVD showed a significantly lower pain-free rate compared with patients without previous MVD (P = 0.01). There was no statistical significance in the recurrence rate (P = 0.82) or the complications (P = 0.93) in the 2 groups during the long-term follow-up period. Conclusions For patients with recurrent TN who previously underwent MVD, GKS remains an efficacious and safe mode of treatment.

Monodispersed 3D core–shell superspheres consisting of oriented MoS2 nanosheets have been successfully synthesized on the large scale with a one-pot approach combining soft- and self-templated methods. Specifically, MoOx (x = 2–3) nanoclusters and MoS2 layers first self-assemble together with (CTAB)2Sy (y = 1 or 2) to form solid hybrids, MoOx–MoS2@(CTAB)2Sy spheres at 160 °C, and most of the MoOx nanoclusters then convert to MoO2 and 2H-MoS2 at 180 and 200 °C, respectively. 3D core–shell superspheres can be finally constructed with 2H/1T-MoS2 nanosheets with abundant O-dopants and defects at 220 °C. The expanded d-spacings of the (002) crystal plane reveal the formation of quasi molecular superlattices for partially intercalating (CTAB)2S molecules into 2D MoS2 nanosheets. The dynamic composition and nano/microstructural evolution of the materials in a one-pot reaction demonstrates a mimicked embryo formation based on in situ anion-exchange. The 3D core–shell superspheres can be applied to assemble anodes for lithium ion batteries (LIBs) with excellent performance, after being coated with reduced graphene oxide (RGO).

It is still a challenge to develop sensing materials towards rapidly and sensitively detecting aniline at 5 ppm. Herein, an in situ “detector/conductor” strategy is reported to design of double-layered MoO3/MoO2 nanoreactors for superior aniline detection. Hollow MoO2 microspheres were prepared and subsequently applied to produce MoO3/MoO2 via an in situ oxidation procedure. The dynamic transformation was monitored by operando XRD device. Metallic MoO2 substrates act as the “conductor” to improve the electroconductivity, and the semiconductive MoO3 play the role of the “detector” to sense the toxic gas. As a result, the response of the optimized MoO3/MoO2-3 sensor was 14.7 to 5 ppm aniline at 200 °C, and the recover and recover time were only 16 and 21 s. The response was much higher than other results reported by far. Density functional theory results revealed that the band structures and adsorption energies of MoO3 to aniline molecules can be modulated via introducing MoO2.

How to improve the selectivity and sensitivity of semiconductor metal oxide (SMO) based gas sensors at room temperature is still a big challenge. In this paper, different content of Ce doped ZnO porous nanosheets were successfully synthesized via a facile and controllable hydrothermal method and their sensing properties were investigated. 1 at% Ce doped ZnO (CZO-1) sensor exhibited a high response (S = 15.1 for 100 ppm aniline), and excellent selectivity toward aniline against other gases at room temperature compared with pristine ZnO. The abundant oxygen vacancies (OV), high specific surface area and the interface interaction between of CeO2 and ZnO effectively enlarged the resistance variation due to the change in oxygen adsorption. The two-dimensional (2D) porous structure also plays an important role in the excellent sensing performance due to the excellent electron transport capability and abundant gas diffusion channels. DFT study results indicated the interaction between ZnO and aniline could be enhanced by introducing OV and Ce doping. Thus, this work indicated that the CZO composites could be a potential candidate for aniline detection at room temperature.

Monodisperse Cu 2 O-cubes, Cu 2 O-concave cubes and Cu 2 O-octapods supercrystals have been synthesized successfully using a self-assembly approach in the presence of dioctyl sulfosuccinate sodium salt (AOT) surfactant. Specifically, the supercrystals can be prepared by adding aqueous Cu(Ac) 2 solution into butyl alcohol solution of AOT to first assemble nanoreactors and then perform hydrothermal reactions. The structures of the supercrystals can be tailored by simply varying the amount of Cu (Ac) 2 with the same ratio of the Cu(Ac) 2 to ascorbic acid. AOT surfactant was crucial to precisely control the supercrystal morphology. It was demonstrated that the ratio of growth rate along different planes varied by adjusting the amount of Cu(Ac) 2 and the volume ratio of alcohol to water, thus Cu 2 O crystals with cubes, concave cubes, and octapods with the size of 1.2–2.2 μm were obtained. The morphology evolution from cubes, concave cubes to octapods was systematically studied and a facet etching mechanism is proposed. Hence, precise control of the amount of Cu(Ac) 2 enables this facet etching, novel Cu 2 O with concave {100} facets can be fabricated. Photocatalysis investigation on the morphology-controlled Cu 2 O indicates that the Cu 2 O-octapods supercrystals showed the highest amount of H 2 and the best cyclic-stability. This work reveals that morphology-control of supercrystals is important to the development of novel photocatalysis.

ZnO and Pd nanoparticles (NPs) with average diameter of 38 and 10 nm were prepared in advance through a chemical solution method. Pd-functionalized ZnO nanoparticles (Pd@ZnO) were simply synthesized by adding ethanol solution of Pd NPs into ZnO powder, and annealing in argon atmosphere at 500 °C for 1 h after grinding for 30 min. The morphology and structure of the materials were systemically analyzed using Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) techniques. A weak peak in the XRD pattern of Pd@ZnO belonging to the (111) plane of elemental Pd indicated successfully loading of Pd. EDS and TEM results further confirmed successfully coating of Pd NPs onto the surface of ZnO. Sensors using ZnO NPs decorated with Pd (1 wt%) on the surface of exhibited highly elevated sensitivity of 76 in comparing with the response of 36 when based on pure ZnO NPs. In addition, such modification also resulted in a decrease in the operating temperature from 370 to 340 °C for 100 ppm acetone vapor. The sensing mechanism of the sensor based on Pd@ZnO NPs is discussed. Addition of Pd NPs can play an important role in improving the performance of gas sensors, including high sensitivity, good selectivity, and short response/recovery times.

3D mace-like hierarchical ZnO nanoarchitectures consisting of porous single-crystalline nanosheets as well as microrod bundles were synthesized by growing Zn 4 CO 3 (OH) 6 ·H 2 O nanosheets on the surfaces of ZnO microrod bundles on the basis of a facile one-step solution method combined with a successive annealing treatment at 400 °C. The investigation for the evolution mechanism of hierarchical ZnO nanoarchitectures shows that the reaction time, concentrations of reactants together with the surfactant can radically influence the compositions and morphologies of materials generated during the reactions. A potential mechanism is suggested to help in understanding the formation of the hierarchical nanoarchitectures based on the reaction time and the concentrations of reactants effect on the morphologies of the products. The chemical sensors made with 3D mace-like hierarchical ZnO nanoarchitectures reveals enhanced sensing performances with high responses, selectivity as well as stability to acetone vapor.

ZnO/Co3O4 porous nanosheets were successfully developed via modulating the proportions in p-n heterojunction composites by a hydrothermal method. The as-synthesized materials were applied to fabricate sensors to study their gas sensing performance. The response value (S = Ra/Rg) of the ZnO/Co3O4 sensor is calculated to be 67.8 for 50 ppm triethylamine, which is much better than that of as-prepared pristine ZnO. Interestingly, the ZnO/Co3O4 sensor also exhibits a high response to triethylamine even in high humidity (77%). Our work provides a strategy to fast probe triethylamine via design of p-n heterojunction ZnO/Co3O4 sensors.

Nitrogen dioxide (NO 2 ), as a toxic gas, seriously harms the environment and human health. Semiconductor metal oxide (MOS) nanocomposites modified by N-doped graphene quantum dots (N-GQDs) have attracted extensive attention as sensing materials for NO 2 . Here, the N-GQDs modified ZnO composite material was successfully prepared by the hydrothermal method . Compared with pure ZnO, G-Z-2 (N-GQD S doping amount of 2 mL) exhibits excellent sensing performance for NO2. The G-Z-2 based sensor reduces the working temperature from 160 °C to 100 °C. The G-Z-2 is shown to be sensitive to 5 ppm NO2 and has a massively enhanced response of about 11.6 times. The detection limit was as low as 0.1 ppm. Moreover, it shows excellent reproducibility, selectivity and stability for the detection of NO 2 . The highly active N atom doping enhances the electron transfer of ZnO to N-GQD S and the adsorption of NO2 molecules. The heterojunction between ZnO and N-GQD S interface expands the resistance modulation, which improves the sensor sensitivity. This work can provide a promising strategy for improving the NO2 gas sensing performance based on semiconductor metal oxide.

Molybdenum sulfide (MoS2) is a promising materials for lithium ion batteries, while the anodes often suffer from low capacity and poor endurability at high current conditions (≥5 A g−1). Here, CTAB was employed as a soft template and carbon source to prepare monodispersed bulb-like O-MoS2@C nanoreactor for high-rate Li storage through an integrated approach. Specifically, bulb-like nanostructured MoS2 precursor were first prepared by microemulsion method. Rich sulfur vacancies were created along with the oxygen doping in anion exchange reaction. And amorphous carbon derived from CTAB is incorporated in the nanoreactor after annealing treatment. The resultant O-MoS2@C delivered average specific capacities of ~1442 mA h g−1 at 0.2 A g−1 and ~394 mA h g−1 at 5 A g−1, and maintained reversible capacities of 1208 mA h g−1 after 200 cycles and ~361 mA h g−1 after 700 cycles, respectively. Density functional theory (DFT) results indicated that the thermodynamic adsorption and kinetic migration of Li can become effortless through introducing carbon and vacancies. This work provides a controllable approach to produce nanoreactor with vacancies and in-situ carbon incorporated for high-rate and durable Li storage performances.

Hexagonal simonkolleite· (Zn5(OH)8Cl2·H2O) nanosheets were synthesized via a one-pot hydrothermal method. The precursors can be converted to porous ZnO nanosheets consisting of nanoparticles by annealing at higher temperature, and the final ZnO products can inherit the hexagonal shapes of the precursors. The gas sensing properties of the precursors and ZnO nanosheets were also studied systematically. It was found that the annealing temperature can dramatically affect the gas sensing performances of the devices for the tunable microstructures and compositions of the materials. After annealed at 500 °C, the ZnO nanosheets exhibit excellent sensing performances to ethanol of 100 ppm.

Background Evans blue (EB) is the most widely used tracer to assess BBB leakage. However, a well-established method to obtain visualized and quantitative results of EB extravasation is presently unavailable. New Method We reported a novel method to quantify BBB leakage by combining EB and high molecular weight FITC-Dextran (2000 kDa). EB was used for a long circulation duration (60 min) to detect BBB leakage. FITC-Dextran was used for a short circulation duration (10 min) to outline vascular contours. Confocal microscope imaging was used to obtain visualized images of BBB leakage. The result of dividing integrated optical density of EB by vascular areas outlined by FITC-Dextran was treated as the quantification of BBB leakage. Results This method proved workable in quantifying BBB leakage of specific regions in lipopolysaccharide-induced BBB disruption mice and apoE−/− mice. Sections processed with this method enabled further immunofluorescence staining. Through combining the results of EB extravasation and immunofluorescence staining, the colocalization of specific proteins and BBB disruption was achieved. Comparison with Existing Methods Colorimetric and spectrophotometric methods provide us with quantitative results of EB extravasation but fail to locate the specific regions. Fluorescence microscopy imaging can locate specific regions of EB extravasation but a well-established quantitative method is presently unavailable. Our method combines advantages of above two classic methods, providing us with visualized and quantitative information of BBB leakage based on EB extravasation in specific cerebral regions. Conclusions The proposed method proved powerful in quantifying BBB leakage of specific regions, which may benefit studies regarding BBB disruption.

A new noninvasive glucose sensor is developed based on Co3O4 particles (Co3O4 NPs), which are synthesized by a single-step hydrothermal method with uniform structure and size. The electrochemical measurements reveal that the device exhibits outstanding performance for glucose detection, achieving a maximal sensitivity of 2495.79[Formula: see text][Formula: see text]A mM[Formula: see text] cm[Formula: see text] with a high [Formula: see text] of 0.99575, a ultra-low detection limit of 9.3[Formula: see text]nM with a signal-to-noise of 3 and linear range up to 3[Formula: see text]mM. The noninvasive glucose sensor can respond swiftly and selectively due to the high electrocatalytic activity of Co3O4 NPs. The sensor also shows its high sensitivity and selectivity in detecting glucose levels in human blood serum and saliva sample, confirming the application potential of Co3O4 NPs in noninvasive detection of glucose.

Oxygen evolution reaction (OER) is considered as the bottleneck of electrochemical water splitting. Molybdenum disulfide (MoS2) with layered structure has great potential in utilization as OER catalyst. However, lower OER activity of MoS2-based catalysts compared with commercial IrO2 catalysts limited their practical applications. Here, we report the synthesis of monodispersed and uniform yolk-shell structured MoS2 nanoreactors (O–MoS2@Pt) with size distribution of 563 ± 14.8 nm through an oil-water microemulsion method. Interestingly, sulfur vacancy caused by oxygen doping could guide the Pt anchoring to generate uniform nanoparticles (ca. 10.9 nm) onto outer shell. Electron paramagnetic resonance (EPR), X-ray photoelectron spectra (XPS), and X-ray absorption fine structure (XAFS) are employed to synergistically investigate the anchor mechanism. The O–MoS2@Pt nanoreactor with highly activated basal plane and interface presented an overpotential of 244 mV at 10 mA/cm2, and a low Tafel slope of 53 mV/dec, which was much better than commercial IrO2 and most MoS2-based catalysts. Due to the prevention of agglomeration, enhanced mechanical stability, and regulation of gas release, all the developed yolk-shell structured nanoreactors exhibited negligible change of nanostructures and overpotentials after continuous cycling measurements for 24 h. In-situ XRD measurements indicated the endurability of the overall nanoreactor during the OER process. Density functional theory calculations revealed electron structures and thermodynamic reaction barriers can be efficiently modulated through introducing vacancy and Pt nanoparticles decorating, leading to highly improved OER activity. Our findings shed a light on the design of highly active catalyst for electrocatalytic water splitting through modulating electron structures and thermodynamic reaction barriers.

LiCoO2 is still the potential first choice of cathode for lithium ion batteries due to the superior tap density of 4.1 g cm−3 and high theoretical specific capacity of 274 mAh g−1. However, the reversible capacity and cycle performance are restricted due to structural instability at high voltage (≥4.5 V). In this work, the problem will be improved by multiple synergistic effect of nano-Ag. The flake-like LiCoO2/Ag cathodes are firstly synthesized by solid state reaction and the following calcination. The structural characteristics reveal that Ag nanoparticles with ca. 10 nm are uniformly embedded into LiCoO2 particles. The initial discharge specific capacity of LiCoO2 is increased by 12% by introducing nano-Ag at 100 mA g−1 (∼0.7C) between 3.0–4.5 V, and after 100 cycles, the discharge specific capacity is enhanced by 52%. Furthermore, when the current density is increased to 2000 mA g−1, the specific capacity retention of LiCoO2/Ag researches to 62%, higher than 52% of LiCoO2. The results clearly indicate that LiCoO2/Ag cathode exhibits excellent specific capacities, enhanced cycle stability and rate performances enabled by nano-Ag through enhancing Li ions diffusion, electron transport and improving structural stability.

Multifunctional catalysts are highly attractive for green oxidation process integrating excellent conversion and selectivity with high separability and recyclability. In this regards, a facile method is developed to fabricate yolk–shell microspheres consisting of Fe3O4 cores, mesoporous CeO2 shells and loaded Pd nanoparticles. Microspheres with 2.6 % Pd loading exemplify excellent catalytic activity for solvent-free, selective oxidation of benzyl alcohol to benzaldehyde by molecular oxygen at 373 K and atmospheric pressure, resulting in 80.5 % conversion of benzyl alcohol with 94.8 % selectivity for benzaldehyde. The catalyst can be magnetically separated and recycled without significant loss of catalytic efficiency even after seven catalytic runs.