Nanoparticles Assembled Microspheres as a High-Rate Cathode Material for Sodium Ion Batteries
12
Citation
36
Reference
10
Related Paper
Citation Trend
Abstract:
P2-type Na0.65Mn0.6Ni0.35Cu0.05O2 microspheres assembled irregularly with massive primary nanoparticles are prepared via hydrothermal method and subsequent two-step calcination process. As expected, the P2-type Na0.65Mn0.6Ni0.35Cu0.05O2 microspheres show superior electrochemical performance in terms of high-rate capability and long-period cycling stability. This material exhibits a reversible capacity of 81 mA h g−1 and exceptional capacity retention up to 79% over 150 cycles even at the high current density of 1 A g−1. The distinctive spherical structure with high specific surface area can be accountable to the excellent electrochemical properties, which offers abundant surface sodium storage sites and shortened diffusion paths of sodium ions. Therefore, this work puts forward a feasible method to design nanoparticles assembled microspheres for layered oxides with high-rate performance as a promising cathode material for sodium ion batteries.Keywords:
Specific surface area
To get CaTiO3catalyst with high photocatalytic properties,the effect of calcination conditions,on the photocatalytic activity of CaTiO3 was investigated.The calcination conditions included heating rate of calcination precursors,calcination temperature,calcination time and cooling rate of calcination products,The catalyst was synthesized by solid-state reaction method with Ca(NO3)2and TiO(OH)2as raw materials and NaOH as mineralizer.The physical properties of the catalyst were characterized using XRD and SEM.The experimental results showed that the activity increased until reached a maximum,and then decreased with the increasing heating rate of calcination precursors;the photocatalytic activity decreased drastically with the fast cooling rate of calcination products.Moreover,the optimal values of calcination temperature and calcination time were obtained.As a result,the CaTiO3catalysts with high photocatalytic activity can be obtained under an optimized calcination conditions after loading CoO(0.2 wt%)co-catalyst.
Cite
Citations (0)
Abstract The rates of calcination of two types of limestones, ranging in particle size from 1 to 90 μm, were measured over the temperature range 516 to 1,000°C. A kinetic model based on the B.E.T. (Brunauer‐Emmett‐Teller method) surface area of the CaCO 3 correlates the results over 5 orders of magnitude in reaction rate. The B.E.T. surface area of CaO formed by rapid calcination in dispersed‐particle systems is 50 to 90 m 2 /g.
Specific surface area
Particle (ecology)
Cite
Citations (262)
Phenolic resin based Activated Carbon Cloths(ACCs) were prepared by carbon dioxide activation treatment,and were used as electrodes of supercapacitors.The pore structure and the electrochemical properties of the resultant ACCs were investigated by means of nitrogen adsorption,AC impedance and constant current discharge techniques.The relationship of pore structure and the electrochemical performance in 1M(CH2CH3)3CH3NBF4/PC were discussed in details.Results showed that the specific capacitance of the samples increase with the BET surface area,and the specific capacitance of ACC4 reached 135 F·g-1 at current density of 50mA·g-1.Besides,the contribution to the specific capacitance from micropores decreases while that of from mesopores increases with the increase of the current density.The conductivity of the sample decreased and the ESR increased with the enhancement of activation degree.
Specific surface area
Carbon fibers
Constant current
Cite
Citations (1)
Al-pillared montmorillonite prepared with Keggin cation and the calcined products at different temperature were studied by means of XRD, specific surface area analyses and pore size distribution. The results showed that, when calcined from 300 to 650℃, the d value of pillared-montmorillonite changed from 2.13nm to 1.74nm, and the specific surface area was increased to 231.6m2/g. The microporosity of pillared montmorillonite changed because of calcination, with the increase of temperature, the specific surface area was reduced, average pore size was increased, and volume of micropores decreased. Calcination destroyed the micro-structure of Al pillared montmorillonite.
Specific surface area
Cite
Citations (0)
Specific surface area
Cite
Citations (1)
This paper is ralate to the effect preparation process of the supported Mn-based catalysts on its surface area.The experimental data show that:the amount of load of the MnOx,the calcination temperature of catalyst and the additives are affect factors of the catalyst specific surface area.With the amount of MnO_x load(MnO_x/TiO_2 molar ratio increased from 0.2~0.5)increased,the catalyst surface area corresponding increase;while with the higher calcination temperature(450 ℃~600 ℃) of the catalyst,and its surface area and pore structure corresponding decreases;Among four kinds of additives(Ce,Ni,Fe,Cu),Ce has the least impact on specific surface area and pore structure of MnO_x/TiO_2.
Specific surface area
Molar ratio
Cite
Citations (0)
Photodegradation
Electrospinning
Specific surface area
BET theory
Morphology
Cite
Citations (59)
Superfine composite powders of CeO2-ZrO2 (CZ) and CeO2-ZrO2-La2O3 (CZL) were prepared by hydrothermal method. The effects of pH?temperature and time for hydrothermal process on the performance of the resulting powders were studied. The optimized reaction parameters were on follows: the precursor′s pH≈9.0, hydrothermal temperature of 200 ℃ holding for 2 h. Thermal stable powders with average particle size smaller than 10 nm and specific surface area of 171 m2·g-1 were obtained. A BET specific surface area was still at 44 m2·g-1 after calcination at 1 000 ℃ for 6 hours.
Specific surface area
BET theory
Hydrothermal reaction
Cite
Citations (0)
Morphology
Specific surface area
Cite
Citations (24)