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1.
Chem Commun (Camb) ; 56(12): 1875-1878, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31950940

RESUMO

Photodetectors play a key role in the military, aerospace, communications, bio-imaging, etc. In this study, we fabricate photodetector devices based on (CH3NH3)2FeCuI4Cl2 (MA2FeCuI4Cl2) and (CH3NH3)2InCuI6 (MA2InCuI6) for the first time. We find that the device based on MA2InCuI6 is highly selective for ultraviolet light (880 nA mW-1) and shows high anti-interference for visible-light (20-50 nA mW-1). The electrochemical impedance results indicate that the value (480 ± 10 Ω) of the resistance based on the MA2InCuI6 photodetector device is much smaller than that (1 ± 0.001 MΩ) based on the MA2FeCuI4Cl2 photodetector device, which in turn proves the difference in photoelectric response.

2.
J Colloid Interface Sci ; 561: 881-889, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767390

RESUMO

The development of low-cost noble metal-free and high-active electrocatalysts for methanol electrooxidation is highly worthwhile but remains a challenge. In this paper, 5, 10, 15, 20-tetrakis(4-carboxylphenyl)porphyrin (H2TCPP) modified nickel-cobalt layer double hydroxides nanosheets (NiCo-LDH) were prepared by one-pot hydrothermal method and characterized by the powder X-ray diffraction (XRD), the scanning electron microscopy (SEM) and X-ray photoelectron spectra (XPS), etc. H2TCPP/NiCo-LDH was demonstrated as superior a photoelectrocatalyst towards methanol oxidation in the alkaline media. Due to the introduction of H2TCPP photosensitizer, H2TCPP/NiCo-LDH exhibits the outstanding photoeletrocatalytic activity toward methanol oxidation under the visible-light irradiation. The great enhancement in the photoelectrocatalytic activity are attributed to high exposed surface active sites, efficient widen adsorption wavelength of H2TCPP in visible region, as well as efficient electron transfer between the electrode surface and the active sites. The H2TCPP/NiCo-LDH nanosheets show mass activity of 246.6 mA mg-1 and specific activity of 34.9 mA cm-2 for methanol oxidation under visible-light, which are 2.32 times higher than that of NiCo-LDH at the same conditions. The developing catalytic activity of H2TCPP/NiCo-LDH for methanol oxidation are attributed to the synergistic effect of H2TCPP and NiCo-LDH. This study may offer new ideas for developing highly effective noble metal-free catalysts for the application in methanol oxidation.

3.
Biosens Bioelectron ; 150: 111846, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31740255

RESUMO

Signal amplification is crucial in electrochemical biosensor to obtain low detection limits. In this work, a highly sensitive sandwich-type thrombin aptasensor is constructed, based on dual signal amplification of uniform silver nanowires (AgNWs) and hollow Au-CeO2 nanocomposites. AgNWs are decorated on the ITO surface to immobilize amino functionalized thrombin capture apemeter 1 (Apt1). And Au nanoparticles (AuNPs) grown directly on the surface of hollow CeO2 microstructure are used to immobilize sulfydryl functionalized thrombin reporter apemeter 2 (Apt2). Thus, sandwich-type apatasensor has been successfully designed, due to the specific recognition between thrombin and the two kinds of aptamers. One of the signal amplifications is from the good conductivity of uniform AgNWs. Moreover, uniform AgNWs together with hollow Au-CeO2 exhibit the good catalytic performance for the reduction of H2O2, further resulting in significant electrochemical signal amplification. Because the electrochemical signal amplification is closely related to the thrombin concentration, differential pulse voltammetry is used to specifically detect thrombin. Under the optimized conditions, the proposed method has a good linear response ranged from 0.5 pM to 30 nM with a low detection limit of 0.25 pM (S/N = 3) for thrombin. The proposed thrombin aptasensor displays good selectivity, reproducibility and stability, providing a good platform for the ultrasensitive detection of thrombin.

4.
ChemSusChem ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31849185

RESUMO

Formamidinium lead iodide-based (FAPbI3 ) perovskite is widely used in the field of photovoltaics, owing to its suitable bandgap (ca. 1.45 eV) and better thermal stability. FAPbI3 has two polymorphs (black α-FAPbI3 and yellow δ-FAPbI3 ) at ambient temperature. The yellow δ-FAPbI3 , which has no photoactivity, has a chain-like structure that likely hinders electron transport and reduces photovoltaic performance. However, pure-phase black α-FAPbI3 without any yellow phase is difficult to obtain and the underlying mechanism of the phase transition is rarely investigated. In this study, a facile bi-additive method (BA method) has been developed to completely eliminate the yellow δ-FAPbI3 phase by inducing a phase transition from δ-FAPbI3 to α-FAPbI3 . HI and Pb(SCN)2 were employed as dual additives. Based on the investigation of the annealing time and temperature, we determined that the BA method can induce the phase transition and enhance the stability of α-FAPbI3 . Owing to the enhanced crystallization as well as uniform morphology of the BA film, the perovskite solar cells (PSCs) exhibited an increased power conversion efficiency (PCE). Furthermore, the optimal devices displayed excellent stability and maintained over 80 % of initial PCE after aging for 400 h in air. This work provides a new insight into the fabrication of high-quality pure α-FAPbI3 perovskite films and makes high efficiency photovoltaic devices a reality.

5.
ACS Appl Mater Interfaces ; 11(47): 44109-44117, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31687795

RESUMO

Aqueous Zn-ion batteries (ZIBs) are a potential electrochemical energy storage device because of their highly intrinsic safety, low cost, and large capacity. However, it is still in the primary stage because of the limited selection of cathode materials with high rate and long-life cycling stability. In addition, the energy storage mechanisms of ZIBs have not been well established. In this work, we report the synthesis of porous V2O3@C materials with high conductivity and further illustrate its application as the intercalation cathode for aqueous zinc-ion batteries. The unique channel and appropriate pore size distribution of corundum-type V2O3 are beneficial to the rapid zinc ion intercalation and removal, leading to a high rate capability. Also, the carbon framework structure achieves a high cyclic stability. The porous V2O3@C cathode delivers high capacities of 350 mA h g-1 at 100 mA g-1, an excellent rate capability (250 mA h g-1 at 2 A g-1), and an impressive long-life cycling stability with 90% capacity retention over 4000 cycles at 5 A g-1. The storage mechanism of zinc ions in the Zn/V2O3 system was studied by various analytical methods and first-principles calculation.

6.
Mikrochim Acta ; 186(12): 755, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707595

RESUMO

Platinum nanoparticles were loaded on CoSn(OH)6 nanocubes via a co-precipitation method. The material (NCs) is shown to be a viable peroxidase mimic that catalyzes the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide (H2O2) to generate oxidized TMB (oxTMB) with absorption at 652 nm. The formation of the blue color can be observed in <30 s. Thus, a visual and colorimetric assay was worked out for H2O2. It has a detection limit as low as 4.4 µM and works in the 5 to 200 µM concentration range. The method was also used to detect dopamine (DA) which is found to inhibit the enzyme mimicking activity of the NCs. Hence, less blue color is formed in its presence. The respective DA assay has a linear response in the 5.0 to 60 µM concentration range and a 0.76 µM detection limit. Graphical abstractSchematic diagram of a visual colorimetric method for determination of H2O2 and dopamine (DA) with the aid of color change of 3,3',5,5'-tetramethylbenzidine (oxTMB), based on the peroxidase-like activity of Pt/CoSn(OH)6 nanocubes.

7.
ACS Appl Mater Interfaces ; 11(42): 38779-38788, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31564106

RESUMO

The most critical reason for limiting the extensive study and promotion of MA-based perovskites is their intrinsic instability when compared to FA-based perovskites. Therefore, it is necessary to develop a simple and effective method to improve their intrinsic stability. Herein, the 1,1,1-trimethylhydrazinium cation (TMH+) was first introduced into MAPbI3 to fabricate high-performance mixed-cation perovskite solar cells (PSCs) with an enhanced power conversion efficiency (PCE) of 19.86%, which benefits by the improved crystallization and morphology of films. On the one hand, the slightly large size of TMH+ is complementary to the low tolerance factor of MAPbI3 and then enhances the structure stability. On the other hand, the presence of methyl groups in TMH+ is beneficial to promote the hydrophobicity of MA-based perovskite. More importantly, the hydrazinium group can effectively inhibit the production of Pb0 in perovskites, which is the initial stage of degradation. As a result, the intrinsic stability of PSCs has been observably boosted. After aging at 45 ± 5% RH for 1800 h and 85 °C for 200 h, the unencapsulated PSCs retained 77 and 79% of initial PCE, respectively. This work provides a new design for the selection of suitable cations with special structures and chemical groups to enhance the moisture resistance and intrinsic stability of MA-based perovskite at the source of degradation.

8.
ACS Omega ; 4(12): 15097-15100, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31552353

RESUMO

The semi-transparent solar cells are promising to be applied in building integrated photovoltaic (BIPV) and tandem solar cells. In this study, we fabricate semi-transparent and stable solar cells for BIPV by utilizing a poly (ethylene oxide) electrolyte and controlling the size of TiO2 nanoparticles and the thickness of the TiO2 film. The power conversion efficiency of the semi-transparent (over 50% transmittance at 620-750 nm) and quasi-solid solar cells is 5.78% under standard AM1.5G, 100 mW cm-2. The higher conductivity and smaller diffusion resistance of the quasi-solid electrolyte inside the mesoporous TiO2 film indicate the confinement effects of the polymer electrolyte inside a mesoporous TiO2 film. The unsealed semi-transparent and quasi-solid solar cell retains its initial efficiency during 1000 h irradiation in humid air.

9.
Analyst ; 144(17): 5284-5291, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31372627

RESUMO

5,10,15,20-Tetrakis(4-carboxyl phenyl)porphyrin (Por) modified Co(OH)2 deposited on the surface of GO nanocomposites (Por/Co(OH)2/GO) were prepared and characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and XRD. For the first time, H2TCPP/Co(OH)2/GO is found to have enhanced peroxidase-like activity and catalyze the oxidation of the substrate 3,3,5,5-tetramethylbenzidine (TMB) by hydrogen peroxide (H2O2). Notably, the colorless TMB rapidly transformed into blue oxTMB in just 60 s, which was easily observed visually. The catalytic kinetics of H2TCPP/Co(OH)2/GO is in accord with the Michaelis-Menten equation. The catalytic mechanism of H2TCPP/Co(OH)2/GO nanocomposites is attributed to hydroxyl radicals (˙OH), due to decomposition of H2O2, which is verified by using terephthalic acid as a fluorescent probe. What's more, H2O2 can be detected in a wide linear detection range from 5 to 35 mM with a detection limit of 0.385 mM. Furthermore, based on the excellent peroxidase-like activity of H2TCPP/Co(OH)2/GO, a colorimetric sensor is established to sensitively detect glutathione (GSH) in a linear range from 10 to 300 µM with a low detection limit of 9.5 µM.


Assuntos
Cobalto/química , Grafite/química , Hidróxidos/química , Nanocompostos/química , Peroxidases/química , Porfirinas/química , Benzidinas/química , Materiais Biomiméticos , Técnicas Biossensoriais/métodos , Catálise , Glutationa/análise , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Cinética , Limite de Detecção , Oxirredução , Sensibilidade e Especificidade , Propriedades de Superfície
10.
Nanomaterials (Basel) ; 9(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261653

RESUMO

A facile one-pot approach was developed for the synthesis of ZnO nanorods (NRs)/nanoparticles (NPs) architectures with controllable morphologies. The concrete state of existence of NPs and NRs could rationally be controlled through reaction temperature manipulation, i.e., reactions occured at 120, 140, 160, and 180 °C without stirring resulted in orderly aligned NRs, disordered but connected NRs/NPs, and relatively dispersed NRs/NPs with different sizes and lengths, respectively. The as-obained ZnO nanostructures were then applied to construct photoanodes of dye-sensitized solar cells, and the thicknesses of the resultant films were controlled for performance optimization. Under an optimized condition (i.e., with a film thickness of 14.7 µm), the device fabricated with the material synthesized at 160 °C exhibited the highest conversion efficiency of 4.30% with an elevated current density of 14.50 mA·cm-2 and an open circuit voltage of 0.567 V. The enhanced performance could be attributed to the coordination effects of the significantly enhanced dye absorption capability arising from the introduced NPs and the intrinsic fast electron transport property of NRs as confirmed by electrochemical impedance spectroscopy (EIS) and ultraviolet-visible (UV-vis) absorption.

11.
ChemSusChem ; 12(4): 795-800, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30628203

RESUMO

Two-dimensional tungsten sulfide is widely applied in electrocatalysis. However, WS2 possesses catalytic active sites located at the layer edge and an inert surface for catalysis. Therefore, increasing the exposure of active sites at the edge and effectively activating the inert sites on the surface is an important challenge. Here, an edge/defect-rich and oxygen-heteroatom-doped WS2 (ED-O-WS2 ) superstructure was synthesized. The power-conversion efficiency (PCE) of dye-sensitized solar cells (DSCs) based on an ED-O-WS2 counter electrode reached 10.36 % (under 1 sun, AM 1.5, 100 mW cm-2 ) and 11.19 % (under 40 mW cm-2 ). These values are, to our knowledge, the highest reported efficiency for DSCs based on Pt-free counter electrodes in I3 - /I- electrolytes. Analysis of the micro/nano structure and the electrocatalytic mechanism indicate that ED-O-WS2 exhibits metallic properties in the electrolyte, and that abundant edges and defects as well as oxygen doping in ED-O-WS2 play an important role in improving the catalytic activity of WS2 . Moreover, ED-O-WS2 displays better catalytic reversibility for I3 - /I- electrolytes than Pt.

12.
Materials (Basel) ; 11(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235798

RESUMO

Hierarchical SnO2 nanocrystallites aggregates (NAs) were prepared with a simple room temperature⁻based aqueous solution method followed by simple freeze-drying treatment. The as-prepared SnO2 NAs were subsequently combined with SnO2 nanosheet⁻based structures from the viewpoint of a function-matching strategy, and under an optimized condition, a power conversion efficiency (PCE) of 5.59% was obtained for the resultant hybrid photoanode, a remarkable 60% enhancement compared to that of dye-sensitized solar cells (DSCs) fabricated with bare SnO2 NAs architecture. The significantly enhanced efficiency can be attributed to the combination of the desirable electron transport property obtained by the intentionally introduced SnO2 nanosheets (NSs) and the effectively retained inherent characteristics of SnO2 NAs, i.e., large surface area and strong light-scattering effect. This work provides a promising approach for the rapid development of highly efficient SnO2 photoanode film-based DSCs with the properties of simplicity of operation and control over the photoanode composition.

13.
R Soc Open Sci ; 5(8): 180897, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225079

RESUMO

Resulting from the drastic increase of atmospheric CO2 concentration day by day, global warming has become a serious environmental issue nowadays. The fixation of CO2 to obtain desirable, economically competitive chemicals has recently received considerable attention. This work investigates the fixation of CO2 along with three bromopyridines via a facile electrochemical method using a silver cathode to synthesize picolinic acids, which are important industrial and fine chemicals. Cyclic voltammetry is employed to investigate the cyclic voltammetric behaviour of bromopyridines. In addition, systematic study is conducted to study the relationships between the picolinic acids' yield and the electrolysis conditions and intrinsic parameters. The results show that the target picolinic acids' yields are strongly dependent on various conditions such as solvent, supporting electrolyte, current density, cathode material, charge passed, temperature and the nature of the substrates. Moreover, in the studied electrode materials such as Ag, Ni, Ti, Pt and GC, electrolysis and cyclic voltammetry show that Ag has a good electrocatalytic effect on the reduction and carboxylation of bromopyridine. This facile electrochemical route for fixation of CO2 provides an indispensable reference for the conversion and utilization of CO2 under mild conditions.

14.
ACS Omega ; 3(10): 13960-13966, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458091

RESUMO

Organic-inorganic hybrid material is a recent hot topic in the scientific community. The best band gap for the entire solar absorption spectrum is about 1.1 eV. However, the lead perovskite band gap is about 1.5 eV. Therefore, developing organic-inorganic hybrid material toward the broader light harvesting of the solar spectrum is extremely urgent. In this study, we prepare three kinds of organic-inorganic hybrid palladium perovskite materials, including (CH3NH3)2PdCl4, (CH3NH3)2PdCl4-x Br x , and CH3NH3PdI3, for an optoelectronic response. The absorption cut offs of (CH3NH3)2PdCl4, (CH3NH3)2PdCl4-x Br x , and CH3NH3PdI3 are approximately 600, 700, and 1000 nm, respectively. The band gaps of (CH3NH3)2PdCl4, (CH3NH3)2PdCl4-x Br x , and CH3NH3PdI3 are determined to be approximately 2.15, 1.87, and 1.25 eV, respectively. To the best of our knowledge, this is the first study that discusses adsorption properties and photoelectric behavior of organic-inorganic hybrid palladium perovskite materials. Interestingly, the photoelectric response of the devices based on CH3NH3PdI3 reaches 950 nm. The results will attract attention in the fields of optical recorders, optical memory, security, light capture, and light treatment.

15.
ACS Omega ; 3(10): 14021-14026, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458097

RESUMO

In this study, all-inorganic copper halide salt K2Cu2Cl6 single-crystal and thin films were prepared. The single-crystal diffraction data belonged to the monoclinic K2Cu2Cl6 (space group = P 2(1)/C, unit cell parameters of a = 4.0340 Å, b = 13.7987 Å, c = 8.7445 Å, α = 90.000, ß = 97.123, and γ = 90.000). As far as we know, this is the first study of the copper halide salt K2Cu2Cl6 for optoelectronic applications. The band gap of K2Cu2Cl6 is calculated to be approximately 1.85 eV. A low-cost photodetector based on the K2Cu2Cl6 thin film was efficient under different monochromatic light from 330 to 390 nm with different chopping frequencies (1.33-30 Hz). Density functional theory (DFT) computational results indicate that the valence bands (VBs) and conduction bands (CBs) are shifted up in energy using the orbital-dependent correction to the DFT energy. Partial density of states reveals that the VBs and narrow CBs are derived from the hybrid orbitals of Cu2+ 3d and Cl- p, respectively.

16.
ACS Omega ; 3(9): 11009-11017, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459211

RESUMO

Splitting of water into hydrogen and oxygen has become a strategic research topic. In the two semi-reactions of water splitting, water oxidation is preferred to the four-electron-transfer process with a higher overpotential (η) and is the decisive step in water splitting. Therefore, efficient water oxidation catalysts must be developed. IrO x and RuO x catalysts are currently the most efficient catalysts in water oxidation. However, the limited reserve and high prices of precious metals, such as Ir and Ru, limit future large-scale industrial production of water oxidation catalysts. In this study, we tune inert Ni-foam into highly active NiOOH/FeOOH heterostructures as water oxidation catalysts via three-step strategy (surface acid-treating, electroplating, and electrooxidation). NiOOH/FeOOH heterostructures as water oxidation catalysts only require η of 257 mV to reach a current density of 10 mA cm-2, which is superior to that of IrO2/Ni-foam (280 mV). The high electrochemically active surface area (72.50 cm2) and roughness factor demonstrate abundant interfaces in NiOOH/FeOOH heterostructures, thus accelerating water oxidation activity. The small value (4.8 Ω cm2) of charge transfer resistance (R ct) indicate that fast electronic exchange occurs between NiOOH/FeOOH heterostructures catalyst and reaction of water oxidation. Hydrogen-to-oxygen volume ratios (approximately 2:1) indicate an almost overall water splitting by the double-electrode system. Faraday efficiency of H2 or O2 is close to 90% at 2:1 hydrogen-to-oxygen volume ratio. NiOOH/FeOOH heterostructures exhibit good stability. The results provide significance in fundamental research and practical applications in solar water splitting, artificial photoelectrochemical cells, and electrocatalysts.

17.
ACS Nano ; 11(7): 7293-7300, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28640994

RESUMO

Dual heteroatom-doped carbon materials are efficient electrocatalysts via a synergistic effect. With nitrogen as the primary dopant, boron, sulfur, and phosphorus can be used as secondary elements for co-doped carbons. However, evaluation and analysis of the promotional effect of B, P, and S to N-doped carbons has not been widely researched. Here we report a robust platform that is constructed through polydopamine to prepare N,B-, N,P-, and N,S-co-doped carbon nanosheets, characterized by similar N species content and efficient B, P, and S doping. Systematic investigation reveals S to have the greatest promotional effect in hydrogen evolution reactions (HER) followed by P and that B decreases the activity of N-doped carbons. Experimental and theoretical analyses show the secondary heteroatom promotional effect is impacted by the intrinsic structures and extrinsic surface areas of both materials, i.e., electronic structures exclusively determine the catalytic activity of active sites, while large surface areas optimize apparent HER performance.

18.
R Soc Open Sci ; 4(12): 171409, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29308262

RESUMO

Three-dimensional (3D) graphene composites have drawn increasing attention in energy storage/conversion applications due to their unique structures and properties. Herein, we synthesized 3D honeycomb-like Ni3S2@graphene oxide composite (3D honeycomb-like Ni3S2@GO) by a one-pot hydrothermal method. We found that positive charges of Ni2+ and negative charges of NO3- in Ni(NO3)2 induced a transformation of graphene oxide with smooth surface into graphene oxide with wrinkled surface (w-GO). The w-GO in the mixing solution of Ni(NO3)2/thioacetamide/H2O evolved into 3D honeycomb-like Ni3S2@GO in solvothermal process. The GO effectively inhibited the aggregation of Ni3S2 nanoparticles. Photoelectrochemical cells based on 3D Ni3S2@GO synthesized at 60 mM l-1 Ni(NO3)2 exhibited the best energy conversion efficiency. 3D Ni3S2@GO had smaller charge transfer resistance and larger exchange current density than pure Ni3S2 for iodine reduction reaction. The cyclic stability of 3D honeycomb-like Ni3S2@GO was good in the iodine electrolyte. Results are of great interest for fundamental research and practical applications of 3D GO and its composites in solar water-splitting, artificial photoelectrochemical cells, electrocatalysts and Li-S or Na-S batteries.

19.
ACS Appl Mater Interfaces ; 8(51): 35163-35171, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27977117

RESUMO

The commercial applications of Mn3O4 in lithium ion batteries (LIBs) are greatly restricted because of the low electrical conductivity and poor cycling stability at high current density. To overcome these drawbacks, mesoporous Mn3O4@C networks were designed and synthesized via an improved bake-in-salt method using NaCl as the assistant salt, and without the protection of inert gas. The added NaCl plays a versatile role during the synthetic process, including the heat conducting medium, removable hard template and protective layer. Because of the homogeneous distribution of Mn3O4 nanoparticles within the carbon matrix, the as-prepared Mn3O4@C networks show excellent cycling stability in LIBs. After cycling for 950 times at a current density of 1 A g-1, the discharge capacity of the as-prepared Mn3O4@C networks is determined to be 754.4 mA h g-1, showing superior cycling stability as compared to its counterparts. The valuable and promising method, simple synthetic procedure and excellent cycling stability of the as-prepared Mn3O4@C networks makes it a promising candidate as the potential anode material for LIBs.

20.
Nanoscale Res Lett ; 11(1): 444, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27699715

RESUMO

MnS has been attracting more and more attentions in the fields of lithium ion batteries (LIBs) because of its high energy density and low voltage potential. In this paper, we present a simple method for the preparation of urchin-like γ-MnS microstructures using L-cysteine and MnCl2 · 4H2O as the starting materials. The urchin-like γ-MnS microstructures exhibit excellent cycling stability (823.4 mA h g-1 at a current density of 500 mA g-1, after 1000 cycles). And the discharge voltage is about 0.75 V, making it a good candidate for the application as the anode material in LIBs. SEM, TEM, and XRD were employed to inspect the changes of the active materials during the electrochemical process, which clearly indicate that the structural pulverization and reformation of the γ-MnS microstructures play important roles for the maintenance of the electrochemical performance during the charge/discharge process.

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