Effects of nano-TiO2 particle size on microstructure and electrochemical performance of TiO2/PEDOT nanocomposites cathode in lithium-sulphur battery

The urban environment is facing serious problems caused by automobile exhaust pollution, which has led to a great impact on human health and climate, and aroused widespread concern of the government and the public. Nano titanium dioxide (TiO2), as a photocatalyst, can be activated by ultraviolet irradiation and then form a strong REDOX potential on the surface of the nano TiO2 particles. The REDOX potential can degrade the automobile exhaust, such as nitrogen oxides (NOx) and hydrocarbons (HC). In this paper, a photocatalytic environmentally friendly pervious concrete (PEFPC) was manufactured by spraying nano TiO2 on the surface of it and the photocatalytic performance of PEFPC was researched. The nano TiO2 particle size, TiO2 dosage, TiO2 spraying amount, and dispersant dosage were selected as factors to investigate the efficiency of photocatalytic degradation of automobile exhaust by PEFPC. Moreover, the environmental scanning electron microscope (ESEM) was used to evaluate the distribution of nano TiO2 on the surface of the pervious concrete, the distribution area of nano TiO2 was obtained through Image-Pro Plus, and the area ratio of nano TiO2 to the surface of the pervious concrete was calculated. The results showed that the recommended nano TiO2 particle size is 25 nm. The optimum TiO2 dosage was 10% and the optimum dispersant dosage was 5.0%. The photocatalytic performance of PEFPC was best when the TiO2 spraying amount was 333.3 g/m2. The change in the photocatalytic ratio of HC and NOx is consistent with the distribution area of nano TiO2 on the surface of the pervious concrete. In addition, the photocatalytic performance of PEFPC under two light sources (ultraviolet light and sunlight) was compared. The results indicated that both light sources were able to stimulate the photocatalytic performance of PEFPC. The research provided a reference for the evaluation of automobile exhaust removal performance of PEFPC.

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Population Balance Application in TiO2 Particle Deagglomeration Process Modeling

Energies ◽

10.3390/en14123523 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3523

Author(s):

Radosław Krzosa ◽

Łukasz Makowski ◽

Wojciech Orciuch ◽

Radosław Adamek

Keyword(s):

Particle Size ◽

Titanium Dioxide ◽

Mechanistic Model ◽

Population Balance ◽

Tio2 Particle ◽

Application Process ◽

Titanium Dioxide Powder ◽

Dioxide Powder ◽

Computational Fluid Dynamics Cfd ◽

Hydrodynamic Stresses

The deagglomeration of titanium-dioxide powder in water suspension performed in a stirring tank was investigated. Owing to the widespread applications of the deagglomeration process and titanium dioxide powder, new, more efficient devices and methods of predicting the process result are highly needed. A brief literature review of the application process, the device used, and process mechanism is presented herein. In the experiments, deagglomeration of the titanium dioxide suspension was performed. The change in particle size distribution in time was investigated for different impeller geometries and rotational speeds. The modification of impeller geometry allowed the improvement of the process of solid particle breakage. In the modelling part, numerical simulations of the chosen impeller geometries were performed using computational-fluid-dynamics (CFD) methods whereby the flow field, hydrodynamic stresses, and other useful parameters were calculated. Finally, based on the simulation results, the population-balance with a mechanistic model of suspension flow was developed. Model predictions of the change in particle size showed good agreement with the experimental data. Using the presented method in the process design allowed the prediction of the product size and the comparison of the efficiency of different impeller geometries.

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Probing the Effect of High Energy Ball Milling on the Structure and Properties of LiNi1/3Mn1/3Co1/3O2 Cathodes for Li-Ion Batteries

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4034755 ◽

2016 ◽

Vol 13 (3) ◽

Cited By ~ 5

Author(s):

Malcolm Stein ◽

Chien-Fan Chen ◽

Matthew Mullings ◽

David Jaime ◽

Audrey Zaleski ◽

...

Keyword(s):

Particle Size ◽

Electrochemical Performance ◽

Crystallite Size ◽

Ball Milling ◽

Lithium Ion ◽

High Energy ◽

Li Ion Batteries ◽

Structure And Properties ◽

Transfer Resistance ◽

Li Ion

Particle size plays an important role in the electrochemical performance of cathodes for lithium-ion (Li-ion) batteries. High energy planetary ball milling of LiNi1/3Mn1/3Co1/3O2 (NMC) cathode materials was investigated as a route to reduce the particle size and improve the electrochemical performance. The effect of ball milling times, milling speeds, and composition on the structure and properties of NMC cathodes was determined. X-ray diffraction analysis showed that ball milling decreased primary particle (crystallite) size by up to 29%, and the crystallite size was correlated with the milling time and milling speed. Using relatively mild milling conditions that provided an intermediate crystallite size, cathodes with higher capacities, improved rate capabilities, and improved capacity retention were obtained within 14 μm-thick electrode configurations. High milling speeds and long milling times not only resulted in smaller crystallite sizes but also lowered electrochemical performance. Beyond reduction in crystallite size, ball milling was found to increase the interfacial charge transfer resistance, lower the electrical conductivity, and produce aggregates that influenced performance. Computations support that electrolyte diffusivity within the cathode and film thickness play a significant role in the electrode performance. This study shows that cathodes with improved performance are obtained through use of mild ball milling conditions and appropriately designed electrodes that optimize the multiple transport phenomena involved in electrochemical charge storage materials.

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Rat pulmonary responses to inhaled nano-TiO2: effect of primary particle size and agglomeration state

Particle and Fibre Toxicology ◽

10.1186/1743-8977-10-48 ◽

2013 ◽

Vol 10 (1) ◽

pp. 48 ◽

Cited By ~ 31

Author(s):

Alexandra Noël ◽

Michel Charbonneau ◽

Yves Cloutier ◽

Robert Tardif ◽

Ginette Truchon

Keyword(s):

Particle Size ◽

Primary Particle ◽

Primary Particle Size ◽

Nano Tio2 ◽

Agglomeration State

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Influence of nitrogen and air atmosphere during thermal treatment on micro and nano sized powders and sintered TiO2 specimens

Science of Sintering ◽

10.2298/sos1403365l ◽

2014 ◽

Vol 46 (3) ◽

pp. 365-375

Author(s):

N. Labus ◽

S. Mentus ◽

Z.Z. Djuric ◽

M.V. Nikolic

Keyword(s):

Phase Transition ◽

Particle Size ◽

Powder Particle ◽

Rutile Phase ◽

Nitrogen Atmosphere ◽

Powder Particle Size ◽

Nano Tio2 ◽

Thermo Gravimetric ◽

Air Atmosphere ◽

Thermal Techniques

The influence of air and nitrogen atmosphere during heating on TiO2 nano and micro sized powders as well as sintered polycrystalline specimens was analyzed. Sintering of TiO2 nano and micro powders in air atmosphere was monitored in a dilatometer. Non compacted nano and micro powders were analyzed separately in air and nitrogen atmospheres during heating using thermo gravimetric (TG) and differential thermal analysis (DTA). The anatase to rutile phase transition temperature interval is influenced by the powder particle size and atmosphere change. At lower temperatures for nano TiO2 powder a second order phase transition was detected by both thermal techniques. Polycrystalline specimens obtained by sintering from nano powders were reheated in the dilatometer in nitrogen and air atmosphere, and their shrinkage is found to be different. Powder particle size influence, as well as the air and nitrogen atmosphere influence was discussed.

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Preparation of La0.75Sr0.25Cr0.5Mn0.5O3-δ Nanometer Powders by Sol-Gel Method and Research about its Electrochemical Performance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.257 ◽

2013 ◽

Vol 712-715 ◽

pp. 257-261

Author(s):

Yin Lin Wu ◽

Qing Hui Wang ◽

Ling Wang ◽

Hai Yan Zhao

Keyword(s):

Heat Treatment ◽

Particle Size ◽

Electrochemical Performance ◽

Heat Treatment Temperature ◽

Sol Gel ◽

Treatment Temperature ◽

Preparation Process ◽

Gel Method ◽

Sol Gel Method ◽

Ft Ir

The La0.75Sr0.25Cr0.5Mn0.5O3-δnanometer powders were prepared by citric acid sol-gel method.The samples were characterized by DTA, FT-IR, XRD, TEM techniques. The preparation process, morphology of synthesized powders, the best heat-treatment temperature and the electrochemical performance had been studied. The results show that the spherical nanometer powders can be obtained and the best heat-treatment temperature is 800°C. The particle size is about 30nm and Ea is 0.071 eV.

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Enhanced Antibacterial Activity of Silver Doped Titanium Dioxide-Chitosan Composites under Visible Light

Materials ◽

10.3390/ma11081403 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1403 ◽

Cited By ~ 9

Author(s):

Jie Li ◽

Bing Xie ◽

Kai Xia ◽

Yingchun Li ◽

Jing Han ◽

...

Keyword(s):

Particle Size ◽

Antibacterial Activity ◽

Titanium Dioxide ◽

Visible Light ◽

Silver Ions ◽

Antibacterial Activities ◽

Nano Tio2 ◽

Inverse Emulsion ◽

Potential Applications

Nano titanium dioxide (TiO2) with photocatalytic activity was firstly modified by diethanolamine, and it was then doped with broad spectrum antibacterial silver (Ag) by in situ method. Further, both Ag doped TiO2-chitosan (STC) and TiO2-chitosan (TC) composites were prepared by the inverse emulsion cross-linking reaction. The antibacterial activities of STC composites were studied and their antibacterial mechanisms under visible light were investigated. The results show that in situ doping and inverse emulsion method led to good dispersion of Ag and TiO2 nanoparticles on the cross-linked chitosan microsphere. The STC with regular particle size of 1–10 μm exhibited excellent antibacterial activity against E. coli, P. aeruginosa and S. aureus under visible light. It is believed that STC with particle size of 1–10 μm has large specific surface area to contact with bacterial cell wall. The increased antibacterial activity was attributed to the enhancement of both electron-hole separations at the surface of nano-TiO2 by the silver ions under the visible light, and the synergetic and sustained release of strong oxidizing hydroxyl radicals of nano-TiO2, together with silver ions against bacteria. Thus, STC composites have great potential applications as antibacterial agents in the water treatment field.

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