Publications by authors named "Zilong Zhou"

15 Publications

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A novel linear-correction localization method of acoustic emission source for velocity-free system.

Ultrasonics 2021 May 9;115:106458. Epub 2021 May 9.

School of Resources and Safety Engineering, Central South University, Changsha 410083, China.

To improve the noise immunity to time-difference-of-arrival (TDOA) measurements and reduce the influence of wave velocity measurement error on localization accuracy, a novel linear-correction localization method of acoustic emission (AE) source for velocity-free system based on the TDOA measurements is proposed in this paper. First, the linear equations with unknown wave velocity are constructed by introducing two intermediate variables, and they are solved for the unconstrained least square (LS) solution. Second, the weight matrix is obtained by estimating the equation residuals. Third, the weight matrix and quadratic constraint are imposed on LS estimate to construct the constrained weighted least square (CWLS) criterion. Finally, the linear correction technique is used to minimize the CWLS criterion and obtain the optimal estimate. The proposed method is verified by pencil-lead breaks experiment. The results show that the locating accuracy and stability of the proposed method are higher than those of the traditional methods. Furthermore, simulation tests prove that the proposed method holds the optimal positioning performance and can reach Cramér-Rao lower bound (CRLB) under different TDOA noise powers.
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http://dx.doi.org/10.1016/j.ultras.2021.106458DOI Listing
May 2021

A New Algebraic Solution for Acoustic Emission Source Localization without Premeasuring Wave Velocity.

Sensors (Basel) 2021 Jan 11;21(2). Epub 2021 Jan 11.

School of Resources and Safety Engineering, Central South University, Changsha 410083, China.

The technique of acoustic emission (AE) source localization is critical for studying material failure mechanism and predicting the position of potential hazards. Most existing positioning methods heavily depend on the premeasured wave velocity and are not suitable for complex engineering practices where the wave velocity changes dynamically. To reduce the influence of measurement error of wave velocity on location accuracy, this paper proposes a new algebraic solution for AE source localization without premeasuring wave velocity. In this method, the nonlinear TDOA equations are established and linearized by introducing two intermediate variables. Then, by minimizing the sum of squared residuals of the linear TDOA equations with respect to the AE source coordinate and two intermediate variables separately, the optimal algebraic solution of the AE source coordinate in the least squares sense is obtained. A pencil-lead breaks experiment is performed to validate the positioning effectiveness of the proposed method. The results show that the new method improves the positioning accuracy by more than 40% compared with two pre-existing methods, and the minimum positioning accuracy of the proposed method can reach 1.12 mm. Moreover, simulation tests are conducted to further verify the location performance of the proposed method under different TDOA errors and the number of sensors.
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http://dx.doi.org/10.3390/s21020459DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7828095PMC
January 2021

Prediction of water inflow from fault by particle swarm optimization-based modified grey models.

Environ Sci Pollut Res Int 2020 Nov 23;27(33):42051-42063. Epub 2020 Jul 23.

School of Resources & Safety Engineering, Central South University, Changsha, 410083, Hunan, China.

Water inflow from fault (WIF) and its secondary impacts are the main environmental challenges in the mining industry. Traditional prediction methods for WIF are exceedingly challenging and costly. In this article, two exponentially weighted moving average (EWMA) modified grey models (GMs, i.e., EGM and REGM) were established to predict the WIF. Particle swarm optimization (PSO) algorithm was employed to optimize parameters of the models. Based on actual WIF data from Buliangou coal mine, the optimized models (i.e., EGM-PSO, REGM-PSO) were used to obtain the prediction equations for WIF. To investigate the validity of the proposed models, the differences between actual values and predicted values were analyzed, and comparison results were obtained by the commonly used GM and GM-PSO. Results show that, for the sample with the larger initial particle swarm and smaller inertia weight, there is a faster convergence speed of the PSO algorithm. Particle search efficiency in the PSO-optimized EWMA-GM is higher than that in the GM-PSO. Through the predicted results of WIF, it is found that the REGM-PSO is the best choice for WIF prediction, and the more historical information, the higher the predicted accuracy. Besides, the parameter optimization by the PSO, the EWMA optimization method and optimization of residuals all can improve the predicted accuracy. Predicted results also show that WIF will have a substantial growth in the future. Therefore, reasonable measures (e.g., draining and grouting) need to be taken to mitigate the damage caused by fault water inflow.
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http://dx.doi.org/10.1007/s11356-020-10172-wDOI Listing
November 2020

Tectorigenin enhances PDX1 expression and protects pancreatic β-cells by activating ERK and reducing ER stress.

J Biol Chem 2020 09 20;295(37):12975-12992. Epub 2020 Jul 20.

Research Center of Agriculture and Medicine gene Engineering of Ministry of Education, Northeast Normal University, Changchun, China. Electronic address:

Pancreas/duodenum homeobox protein 1 (PDX1) is an important transcription factor that regulates islet β-cell proliferation, differentiation, and function. Reduced expression of PDX1 is thought to contribute to β-cell loss and dysfunction in diabetes. Thus, promoting PDX1 expression can be an effective strategy to preserve β-cell mass and function. Previously, we established a promoter-dependent luciferase system to screen agents that can promote PDX1 expression. Natural compound tectorigenin (TG) was identified as a promising candidate that could enhance the activity of the promoter for the gene. In this study, we first demonstrated that TG could promote the expression of PDX1 in β-cells via activating extracellular signal-related kinase (ERK), as indicated by increased phosphorylation of ERK; this effect was observed under either normal or glucotoxic/lipotoxic conditions. We then found that TG could suppress induced apoptosis and improved the viability of β-cells under glucotoxicity and lipotoxicity by activation of ERK and reduction of reactive oxygen species and endoplasmic reticulum (ER) stress. These effects held true as well: prophylactic or therapeutic use of TG could obviously inhibit ER stress and decrease islet β-cell apoptosis in the pancreas of mice given a high-fat/high-sucrose diet (HFHSD), thus dramatically maintaining or restoring β-cell mass and islet size, respectively. Accordingly, both prophylactic and therapeutic use of TG improved HFHSD-impaired glucose metabolism in mice, as evidenced by ameliorating hyperglycemia and glucose intolerance. Taken together, TG, as an agent promoting PDX1 expression exhibits strong protective effects on islet β-cells both and .
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http://dx.doi.org/10.1074/jbc.RA120.012849DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7489913PMC
September 2020

A Closed-Form Method of Acoustic Emission Source Location for Velocity-Free System Using Complete TDOA Measurements.

Sensors (Basel) 2020 Jun 23;20(12). Epub 2020 Jun 23.

School of Resources and Safety Engineering, Central South University, Changsha 410083, China.

A closed-form method of acoustic emission (AE) source location for a velocity-free system using complete time difference of arrival (TDOA) measurements is proposed in this paper. First, this method established the governing equation of unknown acoustic velocity for each sensor; then, the governing equations of each of the three sensors were transformed into a linear equation, which can form a system of linear equations with the complete TDOA measurements. Third, the least squares solutions of the AE source coordinate and acoustic velocity were separately solved by an orthogonal projection operator. The proposed method was verified by the pencil-lead break experiment, and the results showed that the location accuracy and stability of the proposed method were better than those of traditional methods. Moreover, a simulation test was carried out to investigate the influence of noise scales on the location accuracy, and the results further prove that the proposed method holds higher noise immunity than the traditional methods.
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http://dx.doi.org/10.3390/s20123553DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7349182PMC
June 2020

A Weighted Linear Least Squares Location Method of an Acoustic Emission Source without Measuring Wave Velocity.

Sensors (Basel) 2020 Jun 4;20(11). Epub 2020 Jun 4.

School of Resources and Safety Engineering, Central South University, Changsha 410083, China.

The location of an acoustic emission (AE) source is crucial for predicting and controlling potential hazards. In this paper, a novel weighted linear least squares location method for AE sources without measuring wave velocity is proposed. First, the governing equations of each sensor are established according to the sensor coordinates and arrival times. Second, a mean reference equation is established by taking the mean of the squared governing equations. Third, the system of linear equations can be obtained based on the mean reference equation, and their residuals are estimated to obtain their weights. Finally, the AE source coordinate is obtained by weighting the linear equations and inserting the parameter constraint. The AE location method is verified by a pencil lead break experiment, and the results show that the locating accuracy of the proposed method is significantly higher than that of traditional methods. Furthermore, the simulation test proves that the proposed method also has a better performance (location accuracy and stability) than the traditional methods under any given scale of arrival errors.
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http://dx.doi.org/10.3390/s20113191DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309039PMC
June 2020

Acute cocaine treatment enhances the antagonistic allosteric adenosine A2A-dopamine D2 receptor-receptor interactions in rat dorsal striatum without increasing significantly extracellular dopamine levels.

Pharmacol Rep 2020 Apr 2;72(2):332-339. Epub 2020 Mar 2.

Department of Neuroscience, Karolinska Institutet, Biomedicum 8B Solnavägen 9, 171 65, Solna, Sweden.

Background: Antagonistic adenosine A2A receptor (A2AR)-dopamine D2 receptor (D2R) receptor-receptor interactions have previously been demonstrated in A2AR-D2R heteroreceptor complexes in the rat dorsal striatum. They mainly involve a reduction of affinity in the high-affinity component of the D2R agonist binding site upon activation in vivo of the A2AR by an A2AR agonist. Upon cocaine self-administration, this antagonistic A2AR-D2R interaction disappeared in the dorsal striatum.

Methods: In the current experiments, it was tested whether such modifications in the antagonistic A2AR-D2R receptor-receptor interactions can develop also after an acute systemic injection of a low cocaine dose (1 mg/kg; sc).

Results: Microdialysis experiments indicated that acute cocaine did not significantly alter the extracellular dopamine levels in the dorsal striatum of the awake Wistar rats. Competition dopamine receptor binding experiments demonstrated that in the acute cocaine group, the A2AR agonist CGS-21680 produced significantly larger increases in the D2R K values (reduction of high-affinity) versus the saline-injected (i.e. control) group. Furthermore, in the dorsal striatum membrane preparation from acute cocaine-injected rats, CGS-21680 also produced significant increases in the D2R K values (reduction of low-affinity) and in the proportion of D2Rs in the high-affinity state (RH). Such significant effects were not observed with CGS-21680 in the control group.

Conclusions: The molecular mechanism involved in the acute cocaine-induced increase in the antagonistic allosteric A2AR-D2R receptor-receptor interactions may be an increased formation of higher-order complexes A2AR-D2R-sigma1R in which cocaine by binding to the sigma1R protomer also allosterically enhances the inhibitory A2AR-D2R interaction in this receptor complex.
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http://dx.doi.org/10.1007/s43440-020-00069-3DOI Listing
April 2020

A2AR Transmembrane 2 Peptide Administration Disrupts the A2AR-A2AR Homoreceptor but Not the A2AR-D2R Heteroreceptor Complex: Lack of Actions on Rodent Cocaine Self-Administration.

Int J Mol Sci 2019 Dec 3;20(23). Epub 2019 Dec 3.

Department of Neuroscience, Karolinska Institutet, 16175 Stockholm, Sweden.

It was previously demonstrated that rat adenosine A2AR transmembrane V peptide administration into the nucleus accumbens enhances cocaine self-administration through disruption of the A2AR-dopamine (D2R) heteroreceptor complex of this region. Unlike human A2AR transmembrane 4 (TM4) and 5 (TM5), A2AR TM2 did not interfere with the formation of the A2AR-D2R heteroreceptor complex in cellular models using BRET assay. A2AR TM2 was proposed to be part of the of the receptor interface of the A2AR homomer instead and was therefore tested in the current article for effects on rat cocaine self-administration using rat A2AR synthetic TM2 peptide bilaterally injected into the nucleus accumbens. The injected A2AR TM2 peptide failed to significantly counteract the inhibitory action of the A2AR agonist CGS 21680 (0.1 mg/Kg) on cocaine self-administration. In line with these results, the microinjected A2AR TM2 peptide did not reduce the number of proximity ligation assay blobs identifying A2AR-D2R heteroreceptor complexes in the nucleus accumbens. In contrast, the A2AR TM2 peptide significantly reduced the number of A2AR-A2AR homoreceptor complexes in the nucleus accumbens. As to effects on the receptor-receptor interactions in the A2AR-D2R heteroreceptor complexes, the A2AR TM2 peptide did not alter the significant increase in the D2R Ki, high values produced by the A2AR agonist CGS 21680 ex vivo in the ventral striatum. The results indicate that the accumbal A2AR-A2AR homomeric complexes are not involved in mediating the A2AR agonist-induced inhibition of cocaine self-administration.
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http://dx.doi.org/10.3390/ijms20236100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6928905PMC
December 2019

OSU-6162, a Sigma1R Ligand in Low Doses, Can Further Increase the Effects of Cocaine Self-Administration on Accumbal D2R Heteroreceptor Complexes.

Neurotox Res 2020 Feb 28;37(2):433-444. Epub 2019 Nov 28.

Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.

Cocaine was previously shown to act at the Sigma1R which is a target for counteracting cocaine actions. It therefore becomes of interest to test if the monoamine stabilizer (-) OSU-6162 (OSU-6162) with a nanomolar affinity for the Sigma1R can acutely modulate in low doses the effects of cocaine self-administration. In behavioral studies, OSU-6162 (5 mg/kg, s.c.) did not significantly change the number of active lever pressing and cocaine infusions. However, a trend to reduce cocaine readouts was found after 3 days of treatment. In contrast, in maintenance of cocaine self-administration, the proximity ligation assay performed on brains from rats pretreated with OSU-6162 showed highly significant increases in the density of the D2R-Sigma1R heteroreceptor complexes in the shell of the nucleus accumbens versus OSU-6162 induced increases in this region of yoked saline rats. In cocaine self-administration, highly significant increases were also induced by OSU-6162 in the A2AR-D2R heteroreceptor complexes in the nucleus accumbens shell versus vehicle-treated rats. Furthermore, ex vivo, the A2AR agonist CGS21680 (100 nM) produced a marked and significant increase of the D2R Ki high values in the OSU-6162-treated versus vehicle-treated rats under maintenance of cocaine self-administration. These results indicate a substantial increase in the inhibitory allosteric A2AR-D2R interactions following cocaine self-administration upon activation by the A2AR agonist ex vivo. The current results indicate that OSU-6162 via its high affinity for the Sigma1R may increase the number of accumbal shell D2R-Sigma1R and A2AR-D2R heteroreceptor complexes associated with further increases in the antagonistic A2AR-D2R interactions in cocaine self-administration.
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http://dx.doi.org/10.1007/s12640-019-00134-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6989596PMC
February 2020

The role of gangue on the mitigation of mining-induced hazards and environmental pollution: An experimental investigation.

Sci Total Environ 2019 May 5;664:436-448. Epub 2019 Feb 5.

School of Resources & Safety Engineering, Central South University, Changsha, 410083, Hunan, China.

Gangue, produced from coal mining and washing process, is a serious threat to the ground environment. Gangue backfilling mining method can solve this problem and reduce mining-induced hazards, e.g., controlling surface subsidence and preventing water inrush from seeping into goaf by cracks in overlying strata. In this paper, effects of the original particle size distribution (PSD) and water content on the particle crushing behavior and seepage properties of granular gangues were investigated. Experimental results show that the crushing behavior can promote the compaction of gangue particles; the variation of PSD after crushing reveals distinct fractal characteristics. With the increasing compression stress, the particle crushing ratio and fractal dimension increase, while the permeability decreases. Due to the rearrangement of particles and newly generated fine particles filled the gap among larger particles, it is difficult to reduce the permeability by increasing the compressive stress. In addition, the variation of fractal dimensions is similar to the crushing ratio, so the particle crushing can be illustrated by fractal dimensions. The relationship between porosity and permeability established by the Kozeny-Carman equation can model the effect of particle crushing in this research. The reliability of the equation is verified by the comparison of model result and experimental data. To increase the mitigation rate of mining-induced hazards and environmental pollution by GBM method, granular gangues can be crushed into smaller particles and dehydrated before backfilling.
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http://dx.doi.org/10.1016/j.scitotenv.2019.02.059DOI Listing
May 2019

A novel nanocomposite based on fluorescent turn-on gold nanostars for near-infrared photothermal therapy and self-theranostic caspase-3 imaging of glioblastoma tumor cell.

Colloids Surf B Biointerfaces 2018 Oct 18;170:303-311. Epub 2018 Jun 18.

School of Life Sciences, Ludong University, Yantai 264025, China. Electronic address:

We demonstrated a novel nanocomposite based on fluorescent turn-on gold nanostars for simultaneous tumor targeting photothermal therapy (PTT) and feedback apoptosis imaging of the self-therapeutic effect. In this theranostic agent ([email protected]), gold nanostars (AuNSs) and fluorescent dye Atto 655, as a fluorophore/quencher pair, were conjugated to form intermolecular fluorescence quenching in virtue of the linkage of a caspase-3 responsive peptide. Folic acid targeting moiety facilitated the selective accumulation in cancer cells via receptor-mediated endocytosis. Upon photo irradiation, [email protected] demonstrated excellent photothermal effect and induced cell death with apoptosis related mechanism. The typical apoptosis-effector proteases, caspase-3, was subsequently activated and terminated intramolecular fluorescent quenching process. Obvious fluorescence recovery could be applied to precisely assess the activated caspase-3 expression and the real time therapeutic efficacy. This novel versatile nanocomposite could serve as a theranostic agent for tumor targeting PTT and also provide self-therapeutic monitoring for precise cancer therapeutic applications.
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http://dx.doi.org/10.1016/j.colsurfb.2018.06.021DOI Listing
October 2018

Prohibitin 2 localizes in nucleolus to regulate ribosomal RNA transcription and facilitate cell proliferation in RD cells.

Sci Rep 2018 01 24;8(1):1479. Epub 2018 Jan 24.

Institute of Genetics and Cytology, Northeast Normal University, Changchun, 130024, China.

Prohibitin 2 (PHB2), as a conserved multifunctional protein, is traditionally localized in the mitochondrial inner membrane and essential for maintenance of mitochondrial function. Here, we investigated the role of PHB2 in human rhabdomyosarcoma (RMS) RD cells and found substantial localization of PHB2 in the nucleolus. We demonstrated that PHB2 knockdown inhibited RD cell proliferation through inducing cell cycle arrest and suppressing DNA synthesis. Meanwhile, down-regulation of PHB2 also induced apoptosis and promoted differentiation in fractions of RD cells. In addition, PHB2 silencing led to altered nucleolar morphology, as observed by transmission electron microscopy, and impaired nucleolar function, as evidenced by down-regulation of 45S and 18S ribosomal RNA synthesis. Consistently, upon PHB2 knockdown, occupancy of c-Myc at the ribosomal DNA (rDNA) promoter was attenuated, while more myoblast determination protein 1 (MyoD) molecules bound to the rDNA promoter. In conclusion, our findings suggest that nucleolar PHB2 is involved in maintaining nucleolar morphology and function in RD cells by regulating a variety of transcription factors, which is likely to be one of the underlying mechanisms by which PHB2 promotes tumor proliferation and represses differentiation. Our study provides new insight into the pathogenesis of RMS and novel characterizations of the highly conserved PHB2 protein.
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http://dx.doi.org/10.1038/s41598-018-19917-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5784149PMC
January 2018

Multifunctional nanocomplex for surface-enhanced Raman scattering imaging and near-infrared photodynamic antimicrobial therapy of vancomycin-resistant bacteria.

Colloids Surf B Biointerfaces 2018 Jan 2;161:394-402. Epub 2017 Nov 2.

School of Life Sciences, Ludong University, Yantai 264025, China. Electronic address:

Since vancomycin (Van)-resistant enterococci (VRE) strains first emerged as a serious threat to public health, extensive studies focused on optical imaging and antimicrobial therapy have been performed for monitoring and microbiological control. In this study, we developed silicon 2,3-naphthalocyanine dihydroxide (Nc) and Van functionalized silica-encapsulated, silver-coated gold nanoparticles ([email protected]@[email protected]) as a novel theranostic system for surface-enhanced Raman scattering (SERS) detection and antimicrobial photodynamic therapy (aPDT) of VRE strains. The silver-coated gold nanoparticle, as the SERS-active core, exhibited excellent Raman enhancement efficacy. Results of in vitro bacterial SERS imaging revealed Van-enhanced specific binding affinity toward VRE. Meanwhile, Si(IV) naphthalocyanine, serving as a near-infrared (NIR) photosensitizer, was axially linked to the nanoparticle surface, yielding nanostructured hybrid materials that could photoinactivate VRE. Almost 4-5 logs of bacterial reduction were obtained upon in vitro photodynamic therapy of VRE treated with a nanomolar concentration of the nanocomplex. Mouse infection assays were applied for an in vivo evaluation of VRE lethality. Upon near-infrared light irradiation, this hybrid nanomaterial caused obvious infection regression and even complete eradication compared to the findings in the non-treated groups. Therefore, this novel nanosystem integrating SERS imaging and noninvasive aPDT has huge potential for applications in theranostics with regard to VRE management.
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http://dx.doi.org/10.1016/j.colsurfb.2017.11.005DOI Listing
January 2018

Ectopic expression of the ATP synthase β subunit on the membrane of PC-3M cells supports its potential role in prostate cancer metastasis.

Int J Oncol 2017 Apr 16;50(4):1312-1320. Epub 2017 Feb 16.

The Key Laboratory of Pathobiology, Ministry of Education, The College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China.

Metastatic prostate cancer is associated with high mortality rates. Identification of metastasis-related proteins may facilitate the development of novel therapies for the treatment of metastatic disease. In the present study, we aimed to identify prostate cancer metastasis-associated membrane proteins. We developed a phage-displayed 7-mer peptide library to screen the target peptides that were specifically bound to PC-3M cells with subtractive panning from normal prostate cells and PC-3 prostate cancer cells. A novel short peptide (B04) was found to have high affinity to highly metastatic PC-3M cells. ATP synthase β subunit (ATP5B) was then identified as a binding partner of B04 on the PC-3M cell surface. ATP5B was expressed on the PC-3M cell membrane and on highly malignant human prostate cancer specimens, as shown using multiple methodologies. Furthermore, ATP5B-positive gold particles were detected on the cellular and mitochondrial membranes by immunoelectromicroscopy. These results implied the possibility that ATP5B may translocate from the inner mitochondrial membrane to the outer surface of PC-3M cells. Additional analysis showed that incubation of B04 with PC-3M cells reduced the detection of ATP5B by western blotting and flow cytometry and significantly inhibited the proliferation, invasion and metastasis of PC-3M cells. In conclusion, ATP5B, as a binding partner of a metastasis-related short peptide (B04) on prostate cancer cells, is involved in promoting prostate cancer metastasis. In conclusion, ATP5B may be a promising biomarker and therapeutic target for highly metastatic malignancies.
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http://dx.doi.org/10.3892/ijo.2017.3878DOI Listing
April 2017

Nitrogen-Doped Yolk-Shell-Structured CoSe/C Dodecahedra for High-Performance Sodium Ion Batteries.

ACS Appl Mater Interfaces 2017 Feb 23;9(4):3624-3633. Epub 2017 Jan 23.

Department of Materials Science & Engineering, University of Washington , Seattle, Washington 98195, United States.

In this work, nitrogen-doped, yolk-shell-structured CoSe/C mesoporous dodecahedra are successfully prepared by using cobalt-based metal-organic frameworks (ZIF-67) as sacrificial templates. The CoSe nanoparticles are in situ produced by reacting the cobalt species in the metal-organic frameworks with selenium (Se) powder, and the organic species are simultaneously converted into nitrogen-doped carbon material in an inert atmosphere at temperatures between 700 and 900 °C for 4 h. For the composite synthesized at 800 °C, the carbon framework has a relatively higher extent of graphitization, with high nitrogen content (17.65%). Furthermore, the CoSe nanoparticles, with a size of around 15 nm, are coherently confined in the mesoporous carbon framework. When evaluated as novel anode materials for sodium ion batteries, the CoSe/C composites exhibit high capacity and superior rate capability. The composite electrode delivers the specific capacities of 597.2 and 361.9 mA h g at 0.2 and 16 A g, respectively.
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http://dx.doi.org/10.1021/acsami.6b13153DOI Listing
February 2017