scholarly journals Efficient Stabilization of Na Storage Reversibility by Ti Integration into O′3-Type NaMnO2

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Takuro Sato ◽  
Kazuki Yoshikawa ◽  
Wenwen Zhao ◽  
Tokio Kobayashi ◽  
Hongahally Basappa Rajendra ◽  
...  
Keyword(s):  
Binary System ◽  
Electrode Materials ◽  
Storage System ◽  
Energy Storage System ◽  
Rietveld Analysis ◽  
High Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrode Performance ◽  
The Impact

The development of an energy storage system with abundant elements is a key challenge for a sustainable society, and the interest of Na intercalation chemistry is extending throughout the research community. Herein, the impact of Ti integration into NaMnO2 in a binary system of x NaMnO2–(1–x) TiO2 (0.5≤x≤1) is systematically examined for rechargeable Na battery applications. Stoichiometric NaMnO2, which is classified as an in-plane distorted O′3-type layered structure, delivers a large initial discharge capacity of approximately 200 mAh g-1, but insufficient capacity retention is observed, most probably associated with dissolution of Mn ions on electrochemical cycles. Ti-substituted samples show highly improved electrode performance as electrode materials. However, the appearance of a sodium-deficient phase, Na4Mn4Ti5O18 with a tunnel-type structure, is observed for Ti-rich phases. Among the samples in this binary system, Na0.8Mn0.8Ti0.2O2 (x=0.8), which is a mixture of a partially Ti-substituted O′3-type layered oxide (Na0.88Mn0.88Ti0.12O2) and tunnel-type Na4Mn4Ti5O18 as a minor phase elucidated by Rietveld analysis on both neutron and X-ray diffraction patterns, shows good electrode performance on the basis of energy density and cyclability. Both phases are electrochemically active as evidenced by in situ X-ray diffraction study, and the improvement of reversibility originates from the suppression of Mn dissolution on electrochemical cycles. From these results, the feasibility of Mn-based electrode materials for high-energy rechargeable Na batteries made from only abundant elements is discussed in detail.

scholarly journals Investigation of the impact of mechanical activation on synthesis of the MgO-TiO2 system

2021 ◽  
pp. 22-22
Author(s):  
Natasa Djordjevic ◽  
Milica Vlahovic ◽  
Sanja Martinovic ◽  
Slavica Mihajlovic ◽  
Nenad Vusovic ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Titanium Dioxide ◽  
Diffraction Analysis ◽  
Mechanical Activation ◽  
High Energy ◽  
Composition Analysis ◽  
X Ray Diffraction ◽  
Magnesium Titanate ◽  
X Ray ◽  
The Impact

In this study, a mixture of magnesium oxide and titanium dioxide was mechanically activated in order to investigate the possibility of mechanochemical synthesis of magnesium titanate. Mechanical activation was performed for 1000 min in a high-energy vibro mill (type MH954/3, KHD Humboldt Wedag AG, Germany). The mill is equipped with housing having a horizontally placed shutter. The cylindrical stainless steel working vessel, with inner dimensions of 40 mm in height and 170 mm in diameter, has working elements consisting of two free concentric stainless steel rings with a total weight of 3 kg. The engine power is 0.8 kW. Respecting the optimal amount of powder to be activated of 50-150 g and the stoichiometric ratio of the reactants in the equation presenting the chemical reaction of magnesium titanate synthesis, the starting amounts were 20.2 g (0.5 mol) of MgO and 39.9 g (0.5 mol) TiO2. During the experiments, X-ray diffraction analysis of the samples taken from the reaction system after 60, 180, 330, and 1000 min of mechanical activation was performed. Atomic absorption spectrophotometry was used for chemical composition analysis of samples taken at different activation times. Based on the X-ray diffraction analysis results, it can be concluded that the greatest changes in the system took place at the very beginning of the mechanical activation due to the disturbance of the crystal structure of the initial components. X-ray diffraction analysis of the sample after 1000 min of activation showed complete amorphization of the mixture, but diffraction maxima characteristic for magnesium titanate were not identified. Therefore, the mechanical activation experiments were stopped. Evidently, the energy input was not sufficient to overcome the energy barrier to form a new chemical compound - magnesium titanate. The failure to synthesize magnesium titanate is explained by the low negative Gibbs energy value of -25.8 kJ/mol (despite the theoretical possibility that the reaction will happen), as well as by the amount of mechanical energy entered into the system during activation which was insufficient to obtain the reaction product. Although the synthesis of MgTiO3 was not achieved, significant results were obtained which identify models for further investigations of the possibility of mechanochemical reactions of alkaline earth metals and titanium dioxide.

Measurement of the Strain Distribution in Notch Tip Hydrides With High Energy X-Ray Diffraction and the Impact on Overload Modeling

2010 ◽  
Author(s):  
Matthew Kerr ◽  
Stephanie Tracy ◽  
Mark R. Daymond ◽  
Richard A. Holt ◽  
Jonathon D. Almer
Keyword(s):  
Finite Element ◽  
Strain Distribution ◽  
Process Zone ◽  
High Energy ◽  
X Ray Diffraction ◽  
Strain Fields ◽  
X Ray ◽  
Pressure Tubes ◽  
Notch Tip ◽  
The Impact

The formation of notch-tip hydrides in CANDU® Zr-2.5Nb pressure tubes can significantly reduce their resistance to fracture, particularly during overload conditions. This paper outlines recent high energy X-ray diffraction measurements of notch tip strain fields in Zr-2.5Nb specimens, during both hydride growth and overload. The use of this data to validate continuum Finite Element (FE) and possible inclusion in ‘Process Zone’ models of hydride fracture are also discussed.

Direct Growth of CuO Particles on Carbon Papers for High-Performance Rechargeable Li–O2 Batteries

2021 ◽  
Vol 21 (7) ◽  
pp. 3903-3908
Author(s):  
Inhan Kang ◽  
Jungwon Kang
Keyword(s):  
Electron Microscopy ◽  
Energy Efficiency ◽  
Field Emission ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Storage System ◽  
Energy Storage System ◽  
High Energy ◽  
Heating Process ◽  
X Ray

Lithium–oxygen (Li–O2) batteries are considered as a promising high-energy storage system. However, they suffer from overpotential and low energy efficiency. This study showed that CuO growth on carbon using facile synthesis (simple dipping and heating process) reduces overpotential, thus increasing the energy efficiency. We confirmed the structure of CuO on carbon using X-ray diffraction pattern, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and field-emission transmission electron microscopy. The cathode of CuO on carbon shows an average overpotential reduction of ˜6% charge/discharge during 10 cycles in nonaqueous Li–O2 batteries. The possible reason for the reduced charge overpotential of the cathode of CuO on carbon is attributed to the formed Li2O2 of smaller particle size during discharging compared to pristine carbon.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim
Keyword(s):  
Ionic Conductivity ◽  
Electrochemical Impedance ◽  
Structural Information ◽  
Impedance Analysis ◽  
High Energy ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Powder Morphology ◽  
X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

In situ X-ray diffraction techniques as a powerful tool to study battery electrode materials

2002 ◽  
Vol 47 (19) ◽  
pp. 3137-3149 ◽  
Author(s):  
M. Morcrette ◽  
Y. Chabre ◽  
G. Vaughan ◽  
G. Amatucci ◽  
J.-B. Leriche ◽  
...  
Keyword(s):  
Electrode Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Battery Electrode

scholarly journals Life Cycle Assessment of an Innovative Hybrid Energy Storage System for Residential Buildings in Continental Climates

2021 ◽  
Vol 11 (9) ◽  
pp. 3820
Author(s):  
Noelia Llantoy ◽  
Gabriel Zsembinszki ◽  
Valeria Palomba ◽  
Andrea Frazzica ◽  
Mattia Dallapiccola ◽  
...  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Residential Buildings ◽  
Storage System ◽  
Energy Storage System ◽  
Hot Water ◽  
Hybrid Energy ◽  
Hybrid Energy Storage ◽  
Innovative System ◽  
The Impact

With the aim of contributing to achieving the decarbonization of the energy sector, the environmental impact of an innovative system to produce heating and domestic hot water for heating demand-dominated climates is assessed is evaluated. The evaluation is conducted using the life cycle assessment (LCA) methodology and the ReCiPe and IPCC GWP indicators for the manufacturing and operation stages, and comparing the system to a reference one. Results show that the innovative system has a lower overall impact than the reference one. Moreover, a parametric study to evaluate the impact of the refrigerant is carried out, showing that the impact of the overall systems is not affected if the amount of refrigerant or the impact of refrigerant is increased.

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