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For the construction of high-performance energy storage and conversion devices, the development of advanced electrode materials with specific nanostructural characteristics is a requirement of the ...

Hybrid structured electrode materials for supercapacitors have attracted enormous interest. However, the rational design of electrode materials with high conductivity and energy density is still a ...

It is well-known that the excellent cycling stability and high energy density of electrode materials is very important for supercapacitors. However, their actual performance falls far behind and does not satisfy the practical demand. In this study, we synthesized NiCo2S4 nanowire bundles on a nickel foam via facile hydrothermal routes. The as-obtained product as an electrode material possesses excellent specific surface area, which suggests that numerous active sites on the electrode surface can shorten the diffusion channel of ions. The assembled asymmetric supercapacitor delivers an energy density of 57.36 W h kg-1 at 1412.92 W kg-1. Also, it exhibits excellent mechanical stability even at different bending angles.

Hybrid structured semiconductor nanomaterials show excellent electrochemical properties due to the synergistic effect between different components. In this work, we report granular α-Fe2O3@FeS2 nanocrystals by a one-pot hydrothermal route. The as-obtained product as an electrode material shows excellent charge transfer ability and cyclic stability. The specific capacitance of an asymmetric hybrid capacitor is 1155.74 mF cm−2 at 2 mA cm−2. In addition, the device delivers a power density of 27.99 mW cm−3 at an energy density of 1.12 mW h cm−3. This suggests that the synthesized composite electrodes can be candidate materials for future energy storage devices.

In this work, we report Co3O4@PPy hybrid structured electrode materials for overall water splitting. The as-synthesized Co3O4/PPy-120 samples present excellent electrocatalytic performances for OER and HER and long durability. It only requires an operating potential of 1.67 V to deliver a current density of 10 mA/cm2 with a remarkable durability for 28 h. The superior electrocatalytic performances mainly can be attributed to the unique heterostructures and the synergistic effects between PPy and Co3O4 electrode materials.

In the past few years, the increasing energy consumption of traditional fossil fuels has posed a huge threat to human health. It is very imperious to develop the sustainable and renewable energy storage and conversion devices with low cost and environment friendly features. Hybrid supercapacitors are emerging as one of the promising energy devices with high power density, fast charge-discharge process and excellent cycle stability. However, morphology and structure of the electrode materials exert serious effect on their electrochemical performances. In this review, we summarized recent progresses in transition metal oxide based electrode materials for supercapacitors. Different synthesis routes and electrochemical performances of electrode materials and storage mechanisms of supercapacitor devices have been presented in details. The future developing trends of supercapacitor based on metal oxide electrode materials are also proposed.

ZnCo2O4 as electrode material for supercapacior has been extensive investigated owing to its unique structure characteristics and high capacitance. However, the conductivity still cannot reach the ...

CoMn layered double hydroxides (CoMn-LDH) are promising electrode materials for supercapacitors because of their excellent cyclic stability. However, they possess relatively low capacitances. In this work, hybrid CoMn-LDH@MnO2 products grown on Ni foams were obtained through a facile hydrothermal method. The as-synthesized samples employed as electrodes deliver a specific capacitance of 2325.01 F g−1 at 1 A g−1. An assembled asymmetric supercapacitor using these products as positive electrodes shows a maximum energy density of 59.73 W h kg−1 at 1000.09 W kg−1. The prominent electrochemical performance of the as-prepared electrodes could be attributes to hierarchical structures. These findings suggest that hybrid structures might be potential alternatives for future flexible energy storage devices.

Developing electrode materials with high specific capacitance and excellent stability for energy storage is necessary to solve energy shortage issues. In this work, we prepare ZnCo2O4@CoMoO4 core-shell structures on nickel foam by a simple hydrothermal approach. The as-synthesized products show excellent electrochemical performances. It reveals that the secondary growth of CoMoO4 nanosheets induces many active sites and facilitates rapid ion and electron transmission. In addition, the as-assembled device delivers high energy density, indicating that the as-obtained samples are excellent candidates for future energy storage applications.

It is an effective strategy to develop novel electrocatalysts with controllable defects to enhance their electrocatalytic activity and stability. However, how to precisely design these catalysts on the atom scale remains very difficult. Herein, several vacancy-dependent CoZn

It is very important to design hybrid core–shell structured electrode materials to obtain superior electrochemical and electrocatalytic performance. In this work, we reported hybrid NiCo2O4@NiWS na...

Dendrite-like MnO2 nanostructures grown on carbon cloth are successfully prepared by a facile one-step route. The as-prepared nanoarchitecture delivers a specific capacity of 430 F g−1 at 1 A g−1 and excellent cycling stability. In addition, a quasi-solid-state asymmetric supercapacitor is assembled by using the dendrite-like MnO2 nanostructures as the positive electrode. It shows an energy density of 20.65 W h kg−1 at a power density of 437.30 W kg−1 at a voltage window of 2.45 V. The results reveal that the as-synthesized MnO2 products might be promising electrode materials for electrochemical energy storage.

Electrode materials with excellent electrochemical performance are very significant for energy storage devices. However, single structured electrode materials present poor conductivity and cycling stability. In this work, we prepare MnO2@NiCo2O4 nanowire arrays by a simple hydrothermal method. The as-fabricated product exhibits a specific capacitance of 452.1 C g−1 at 10 A g−1. The assembled device keeps 82.1% capacitance retention after 10 000 cycles and delivers an energy density of 31.8 W h kg−1 at a power density of 2241.6 W kg−1. This superior electrochemical performance can be ascribed to the unique spatial structure, demonstrating potential application in next generation micro/nanodevices.

It is well-known that the excellent cycling stability and high energy density of electrode materials is very important for supercapacitors. However, their actual performance falls far behind and does not satisfy the practical demand. In this study, we synthesized NiCo

Human leukocyte antigen-G (HLA-G) has been widely acknowledged to play critical roles in fetal-maternal maintenance. However, the significance of using maternal serum sHLA-G to detect prenatal chromosomal abnormality has not been investigated. In China, prenatal screening using maternal α-fetoprotein (AFP), unconjugated estriol (uE3), and free β subunit human chorionic gonadotropin (β-hCG) in the second trimester has been widely applied. In this study, we evaluated the use of sHLA-G as a screening marker, compared with traditional second trimester prenatal screening. Serum samples from 1,019 singleton women in their second trimester were assessed. Among them, 139 infants were confirmed with trisomy 21 (T21) by karyotyping, 83 were confirmed with trisomy 18 (T18), and the remaining 797 infants had no abnormalities. The sHLA-G levels in maternal sera were significantly lower in pregnant women with T18 fetuses (median: 47.8 U/ml, range: 9.8–234.2 U/ml) and significantly higher in those with T21 fetuses (median: 125.7 U/ml, range: 28.7–831.7 U/ml), compared with the normal controls (median: 106.3 U/ml, range: 50.5–1136.4 U/ml) (p < 0.001). The risk values of the screening of T21 or T18 fetuses were assessed using mean and standard deviation log10 analyte multiples of median (MoM) which showed that the predictive values of sHLA-G were the same as free β-hCG, and superior to AFP and uE3 for T18 screening. Logistic regression analysis revealed that sHLA-G MoM was the highest risk factor associated with pregnant women carrying T18 fetuses [Exp(B): 171.26, 95% CI: 36.30–807.97, p < 0.001]. Receiver operating characteristic (ROC) analysis revealed that the area under ROC curve for sHLA-G MoM was 0.915 (95% CI, 0.871–0.959, p < 0.001), for AFP MoM was 0.796 (95% CI, 0.730–0.861, p < 0.001), for free β-hCG MoM was 0.881 (95% CI, 0.829–0.934, p < 0.001), and for uE3 MoM was 0.876 (95% CI, 0.828–0.923, p < 0.001) in the T18 group. sHLA-G MoM demonstrated the best sensitivity and negative predictive value. For the first time, our findings reveal that sHLA-G is a better second trimester screening marker for the detection of T18 fetuses and the combined application of sHLA-G with AFP, free β-hCG, and uE3 could improve clinical screening for T18 fetuses.

Developing electrode materials with high specific capacitance and excellent stability for energy storage is necessary to solve energy shortage issues. In this work, we prepare ZnCo2O4@CoMoO4 core-shell structures on nickel foam by a simple hydrothermal approach. The as-synthesized products show excellent electrochemical performances. It reveals that the secondary growth of CoMoO4 nanosheets induces many active sites and facilitates rapid ion and electron transmission. In addition, the as-assembled device delivers high energy density, indicating that the as-obtained samples are excellent candidates for future energy storage applications.

Developing stable and highly efficient bifunctional electrocatalyst is very important for sustainable energy conversion technology. However, conventional electrocatalytic materials often show high overpotentials and low chemical activities. Conductive polymers anchored is thought an effective strategy to solve this problem. In this work, we report a kind of novel nanosheet arrays through a facile hydrothermal and subsequent electrodeposition process. The as-obtained CoNi2S4@PEDOT-150 products possess an overpotential of 270 mV for oxygen evolution reaction (OER) at 50 mA cm−2 and 90 mV for hydrogen evolution reaction (HER) at 10 mA cm−2 in 1.0 M KOH electrolyte. In addition, the electrode can be used as both anode and cathode for overall water splitting. It only requires a cell voltage of 1.75 V at 50 mA cm−2, which is superior to previous reports.

It is very essential to design an efficient and low-cost electrocatalyst for oxygen evolution reaction (OER). In this work, we report synthesis of Co3O4@Co9S8 heterostructures (Co-HSs) by employing Co3O4 nanowires (Co-NWs) as the precursor on nickel foam though a facile hydrothermal method. The unique structures can combine the advantages of one-dimensional nanowires and two-dimensional nanosheets, simultaneously, which possess plentiful defect atoms and active sites. The as-prepared Co-HSs exhibit excellent electrocatalytic performance for OER, which present a low overpotential of 80 mV at 10 mA cm−2 during OER process and small Tafel slope of 107.2 mV dec−1.

Exploring high-efficient and low-cost electrode materials is very important to improve the energy conversion efficiency of catalysts. Metal oxide generally exhibits poor conductivity that restricts its wide applications. In this work, a series of ZnCo2O4@PPy nanowires are obtained through a facile hydrothermal route and subsequently electrochemical deposition process. Among them, ZnCo2O4@PPy-200 product shows superior OER performance with a low overpotential and Tafel slope of 60.77 mV/dec. As bifunctional catalysts to drive electrolysis of water, the samples deliver a cell voltage of 1.95 V at 100 mA/cm2 and long cycle stability.

To design rationally bi-functional electrocatalysts with high efficiency and rich defects for overall water splitting is greatly desirable. However, some electrode materials often exhibit slow electrons transportation. To address above issues, Mo doped ZnCoP products with high electrocatalytic activities are fabricated through a convenient hydrothermal and phosphating route. The as-obtained Mo-ZnCoP-0.5 products show HER activities with an overpotential of 153.1 mV at −10 mA cm−2 and the overpotential of 280 mV at 50 mA cm−2 for OER. In addition, the as-prepared electrocatalysts present overall water splitting performances with a cell voltage of 1.51 V at 50 mA cm−2, revealing that Mo element doping can effectively regulate the electronic structures of ZnCoP products due to the formation of many defects.

Constructing bi-functional electrocatalysts with multi-active sites is significant to enhance the catalytic performances. However, it is still a large challenge to obtain high efficient catalysts for full water electrolysis. Herein, we design novel sandwich-like FeCo2O4@FeCo2S4@PPy catalysts through a facile preparation strategy. The as-fabricated samples present an excellent electrocatalytic performance with an overpotential of 98.2 mV for HER at −10 mA cm−2, 280 mV for OER and a cell voltage of 1.63 V at 50 mA cm−2. The outstanding performances can be contributed to in-situ electrochemical activation and synergistic effects of electrode materials. It benefits to surface/interface modulation forming active Co and Fe oxyhydroxides in electrochemical reaction process.

To delineate cytogenetic and molecular abnormalities of a fetus carrying a de novo 46,X,der(X),t(X;Y)(p22.3;p11.2).G-banded karyotyping and next-generation sequencing (NGS) were used to analyze the fetus, his father and sister. Single nucleotide polymorphism-based arrays (SNP-array), multiple PCR and fluorescence in situ hybridization (FISH) were utilized to verify the result.G-banded karyotyping at 320 bands showed that the fetus had a normal karyotype, while NGS has identified a 3.58 Mb microdeletion at Xp22.33 and a Y chromosomal segment of about 10 Mb at Yp11.32p11.2. With the sequencing results, high-resolution karyotyping at 550-750 bands level has determined the fetus to be 46,X,der(X)t(X;Y)(p22.3;p11.2). The result was confirmed by PCR amplification of the SRY gene, FISH and SNP-array assays. The karyotypes of his father and sister were both normal. His sister also showed no amplification of the SRY gene, and her NGS results were normal too, suggesting that the karyotype of the fetus was de novo.Combined karyotyping, NGS, SNP-array, PCR and FISH assay can facilitate diagnosis of XX disorder of sex development.

Uterine fibroid is one of the most common solid tumors occurring in reproductive age women. Lack of accurate methods for In vivo quantitative assessment of uterine fibroid progression severely impedes the basic research and drug screen of this disease. To solve this problem, the correlation between bioluminescence imaging (BLI) and initial cell number used to form xenograft was investigated in this study. The results showed that both subcutaneous (SC) and intraperitoneal (IP) D-luciferin administration led to fast increase of bioluminescence signal (BLS) intensity and caused large variation of peak signal intensity of xenografts through the analysis of BLI kinetic curves. We found that a distinct linear stage appeared in xenograft BLI curve for each mouse subjected to IP-injection of D-luciferin. Moreover, a high positive correlation was found between linear slope and the initial number of human uterine fibroid smooth muscle cells (fSMCs) used for xenograft formation. Our research indicates that the slope of linear stage in BLI curve is more appropriate for in vivo quantitative assessment of human uterine fibroid xenograft.

To explore the origin and mechanism of small supernumerary marker chromosomes (sSMC) in order to facilitate genetic counseling.Chromosome karyotypes of two fetuses and their immediate family members were analyzed by conventional G banding. High-throughput whole genome sequencing was used to determine the origin of sSMCs.Fetus 1 was shown to have a karyotype of 47,XY,+mar but with normal FISH and B ultrasound findings. Its father also had a 47,XY,+mar karyotype with normal FISH results and clinical phenotype. High-throughput genome sequencing revealed that fetus 1 and its father were both 46,XY,dup(21)(q11.2;q21.1) with a 6.2 Mb duplication of the long arm of chromosome 21. The fetus was born with normal phenotype and developed well. Its grandmother also had a karyotype of 46,XX,t(15;21)(q13;p13) with normal FISH result and clinical phenotype. The karyotypes of its mother and grandfather were both normal. Analysis of fetus 2 showed a 47,XY,+mar karyotype with normal FISH results. High-throughput genome sequencing suggested a molecular karyotype of 46,XX. The fetus was born with normal phenotype and developed well. The karyotypes of its parents were both normal.Considering their variable origins, identification of sSMC should combine conventional G banding analyses with high-throughput whole genome sequencing for precise delineation of the chromosomes.

To analyze the deletion region for two fetal cases with large Yq deletions in order to provide genetic counseling and prenatal diagnosis.For both cases, amniotic fluid samples were cultured and analyzed with G banding and fluorescence in situ hybridization (FISH). Multiplex polymerase chain reaction was also carried out to amplify 15 sequence tagged sites (STS) of azoospermia factor (AZF) on the Y chromosome.For both samples, the karyotypes were determined as 46,X,del(Y)(pter→q11:). No heterochromatin was found in C band. The karyotypes of their fathers were 46,XY, and heterochromatin was found in C band. STS analyses suggested that only sY82, sY84 and sY86 in AZFa were amplifiable while the other 12 STS were negative in amniotic fluid for the first case, which indicated deletions of AZFb, AZFd and AZFc. No AZF deletion was found in its father. For the second case, all 15 STS were amplifiable in the amniotic fluid, suggesting no AZF deletion. No AZF deletion was found in its father too.Conventional karyotyping combined with FISH and molecular genetics techniques can enable characterization of AZF microdeletions and facilitate genetic counseling and prenatal diagnosis.

To track and analyze two false positive cases from non-invasive prenatal testing for potential fetal aneuploidy.The two cases, respectively reported to have XO (+++) and T18 (1/20) XO(+), were analyzed with conventional karyotyping, fluorescence in situ hybridization (FISH) and massively parallel genomic sequencing (MPS).The first fetus, who was suspected for XO(+++), was verified to have super female syndrome (47,XXX/46,XX) due to confined placental mosaicism by karyotyping of amniotic fluid cells, FISH analysis of placenta and massively parallel sequencing (MPS) of fetal tissue. The second fetus, suspected to have trisomy 18 (1/20) XO(+), was verified to have Turner syndrome by karyotyping, FISH and MPS analyses of umbilical cord blood cells. And the karyotype was 45,X[48]/46, X, der(X) del(X) (p11.21) del(X) (q13.3)[62].Non-invasive prenatal testing carries a risk for false positive diagnosis of fetal sex chromosome and trisomy 18. Combined cytogenetic and molecular techniques are required to ensure an accurate diagnosis.