High performance cobalt nanoparticle catalysts supported by carbon for ozone decomposition: the effects of the cobalt particle size and hydrophobic carbon support

2021 ◽  
Author(s):  
Dandan Li ◽  
Bingheng Cen ◽  
Chentao Fang ◽  
Xingyue Leng ◽  
Weiyue Wang ◽  
...  
Keyword(s):  
Particle Size ◽  
High Performance ◽  
Carbon Support ◽  
Ozone Decomposition ◽  
High Humidity ◽  
Cobalt Particle ◽  
Nanoparticle Catalysts ◽  
Significant Challenge ◽  
Gaseous Ozone ◽  
Cobalt Nanoparticle

Catalytic gaseous ozone decomposition under high humidity is not only an urgent need but also a significant challenge because of the low stability over the available catalysts.

scholarly journals Simultaneous Monitoring of Particle-Bound PAHs Inside a Low-Energy School Building and Outdoors over Two Weeks in France

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 108
Author(s):  
Céline Liaud ◽  
Sarah Chouvenc ◽  
Stéphane Le Calvé
Keyword(s):  
Particle Size ◽  
Air Quality ◽  
High Performance ◽  
Sampling Period ◽  
Temporal Variations ◽  
Ventilation Rate ◽  
Low Energy ◽  
Total Particle ◽  
Polycyclic Aromatic ◽  
Individual Pahs

The emergence of new super-insulated buildings to reduce energy consumption can lead to a degradation of the indoor air quality. While some studies were carried out to assess the air quality in these super-insulated buildings, they were usually focused on the measurement of gas phase pollutants such as carbon dioxide and volatile organic compounds. This work reports the first measurements of Polycyclic Aromatic Hydrocarbons (PAHs) associated with particles as a function of time and particle size in a low-energy building. The airborne particles were collected indoors and outdoors over three to four days of sampling using two three-stage cascade impactors allowing to sample simultaneously particles with aerodynamic diameter Dae > 10 µm, 2.5 µm < Dae < 10 µm, 1 µm < Dae < 2.5 µm, and Dae < 1 µm. The 16 US-EPA priority PAHs were then extracted and quantified by high-performance liquid chromatography (HPLC) coupled to fluorescence detection. The resulting total particle concentrations were low, in the ranges 3.73 to 9.66 and 0.60 to 8.83 µg m-3 for indoors and outdoors, respectively. Thirteen PAHs were always detected in all the samples. The total PAH concentrations varied between 290 and 415 pg m−3 depending on the particle size, the environment (indoors or outdoors) and the sampling period considered. More interestingly, the temporal variations of individual PAHs highlighted that high molecular weight PAHs were mainly associated to the finest particles and some of them exhibited similar temporal behaviors, suggesting a common emission source. The indoor-to-outdoor concentration ratios of individual PAH were usually found close to or less than 1, except during the event combining rainy conditions and limited indoor ventilation rate.

scholarly journals Particle Size Effect of Lanthanum-Modified Bismuth Titanate Ceramics on Ferroelectric Effect for Energy Harvesting

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Sangmo Kim ◽  
Thi My Huyen Nguyen ◽  
Rui He ◽  
Chung Wung Bark
Keyword(s):  
Particle Size ◽  
Energy Harvesting ◽  
High Speed ◽  
High Performance ◽  
Bismuth Titanate ◽  
Vinylidene Fluoride ◽  
Piezoelectric Materials ◽  
Renewable Energy Sources ◽  
Particle Size Effect ◽  
Ferroelectric Materials

AbstractPiezoelectric nanogenerators (PNGs) have been studied as renewable energy sources. PNGs consisting of organic piezoelectric materials such as poly(vinylidene fluoride) (PVDF) containing oxide complex powder have attracted much attention for their stretchable and high-performance energy conversion. In this study, we prepared a PNG combined with PVDF and lanthanum-modified bismuth titanate (Bi4−XLaXTi3O12, BLT) ceramics as representative ferroelectric materials. The inserted BLT powder was treated by high-speed ball milling and its particle size reduced to the nanoscale. We also investigated the effect of particle size on the energy-harvesting performance of PNG without polling. As a result, nano-sized powder has a much larger surface area than micro-sized powder and is uniformly distributed inside the PNG. Moreover, nano-sized powder-mixed PNG generated higher power energy (> 4 times) than the PNG inserted micro-sized powder.

Fabrication, Structural, and Spectroscopic Investigation of Tb-Doped Lu3Al5O12 Phosphor

2005 ◽  
Vol 20 (11) ◽  
pp. 2934-2939 ◽  
Author(s):  
Yikun Liao ◽  
Danyu Jiang ◽  
Tao Feng ◽  
Jianlin Shi
Keyword(s):  
Particle Size ◽  
Crystallization Temperature ◽  
High Performance ◽  
Growth Process ◽  
Solution Combustion Synthesis ◽  
Processing Parameters ◽  
Solution Combustion ◽  
Urea Content ◽  
Emission Intensity Ratio ◽  
Combustion Synthesis Technique

A simple solution combustion synthesis technique was explored to produce Tb3+-doped Lu3Al5O12 (LuAG:Tb) phosphor with particle size in the range from about 25 to 900 nm by using glycine, urea, and the mixture of them as fuels. The effects of processing parameters such as type of fuel, fuel-to-oxidizer ratio and the composition of the complex fuel were studied. An increase in phosphor brightness and a decrease in crystallization temperature with increasing urea content in the fuel were observed. The integrated emission intensity ratio of the 5D3–7Fj transition to the 5D4–7Fj transition as a function of Tb concentration in LuAG was also investigated. It is very interesting that the growth process of the particles exhibited two steps when the content of urea in the complex fuel increased from 0 to 1.0. By tailoring the glycine-to-urea ratio in the fuel, an excellent fuel was found and high performance phosphors were obtained.

scholarly journals Carbon-supported Platinum Electrocatalysts probed in a Gas Diffusion Setup with Alkaline Environment: how Particle Size and Mesoscopic Environment influence the Degradation Mechanism

2020 ◽  
Author(s):  
Shima Alinejad ◽  
Jonathan Quinson ◽  
Johanna Schröder ◽  
Jacob J. K. Kirkensgaard ◽  
Matthias Arenz
Keyword(s):  
Particle Size ◽  
Degradation Mechanism ◽  
Active Phase ◽  
Active Surface ◽  
Carbon Support ◽  
Gas Diffusion ◽  
Active Surface Area ◽  
Electrochemical Cells ◽  
Co Stripping ◽  
Large Particles

In this work, we investigate the stability of four different types of Pt/C fuel cell catalysts upon applying accelerated degradation tests (ADTs) in a gas diffusion electrode (GDE) setup equipped with an anion exchange membrane (AEM). In contrast to previous investigations exposing the catalysts to liquid electrolyte, the GDE setup provides a realistic three-phase boundary of the reactant gas, catalyst and ionomer which enables reactant transport rates close to real fuel cells. Therefore, the GDE setup mimics the degradation of the catalyst under more realistic reaction conditions as compared to conventional electrochemical cells. Combining the determination of the loss in electrochemically active surface area (ECSA) of the Pt/C catalysts via CO stripping measurements with the change in particle size distribution determined by small-angle X-ray scattering (SAXS) measurements, we demonstrate that i) the degradation mechanism depends on the investigated Pt/C catalyst and might indeed be different to the one observed in conventional electrochemical cells, ii) degradation is increased in an oxygen gas atmosphere (as compared to an inert atmosphere), and iii) the observed degradation mechanism depends on the mesoscopic environment of the active phase. The measurements indicate an increased particle growth if small and large particles are immobilized next to each other on the same carbon support flakes as compared to a simple mix of two catalysts with small and large particles, respectively.

Graphene-Ta2O5 Heterostructure Enabled High Performance, Deep-Ultraviolet to Mid-Infrared Photodetection

Nanoscale ◽  
2021 ◽  
Author(s):  
Vinh Ho ◽  
Yifei Wang ◽  
Michael Cooney ◽  
Nguyen Q Vinh
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Low Cost ◽  
Infrared Region ◽  
Temperature Sensitive ◽  
Mid Infrared ◽  
Significant Challenge ◽  
Deep Ultraviolet ◽  
Infrared Photodetection

Ultrafast, high sensitive, low cost photodetectors operating at room temperature sensitive from the deep-ultraviolet to mid-infrared region remain a significant challenge in optoelectronics. Achievements in traditional semiconductors using cryogenic operation...

scholarly journals SYNTHESIS AND STABILITY OF RESVERATROL-CONJUGATED GOLD NANOPARTICLES MODIFIED WITH POLYETHYLENE GLYCOL

2020 ◽  
pp. 230-236
Author(s):  
RADITYA ISWANDANA ◽  
RICHA NURSELVIANA ◽  
SUTRIYO SUTRIYO
Keyword(s):  
Particle Size ◽  
Gold Nanoparticles ◽  
Polyethylene Glycol ◽  
Zeta Potential ◽  
High Performance ◽  
Entrapment Efficiency ◽  
Test Results ◽  
Novel Method ◽  
The Stability ◽  
Phosphate Buffered Saline

Objective: Gold nanoparticles (AuNPs) are highly useful for drug delivery, but their application is limited by their stability as they readily aggregate.This issue can be prevented by adding a stabilizing agent such as resveratrol (RSV), which is a polyphenol derived from plants, that is used to preventcancer. Therefore, we propose a novel method to prepare stable RSV-conjugated nanoparticles modified with polyethylene glycol (RSV-AuNP-PEG).Methods: In the first step, the Turkevich method was used to synthesize the AuNPs. Then, PEG was added as stabilizer agent and conjugated with RSV.The synthesized conjugates were characterized using ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy, particle sizeanalysis, and high-performance liquid chromatography.Results: The obtained RSV-AuNP-PEG had a particle size of 83.93 nm with a polydispersity index (PDI) of 0.562 and formed a translucent purple-redfluid in solution. The zeta potential was −22.9 mV, and the highest entrapment efficiency was 75.86±0.66%. For comparison, the RSV-AuNP solutionwas purple and turbid, the particle size was 51.97 nm with a PDI of 0.694, and the zeta potential was −24.6 mV. The stability test results showed thatthe storage stability of RSV-AuNP-PEG was better than that of AuNP-RSV. Further, the RSV-AuNP-PEG was shown to be most stable in 2% bovine serumalbumin (BSA) while the AuNP-RSV was most stable in 2% BSA in phosphate-buffered saline pH 7.4.Conclusion: These results show that modification of RSV-conjugated AuNPs with PEG effectively prevents their aggregation in storage, but only incertain mediums.

scholarly journals Electrocatalysts: Mulberry‐Inspired Nickel‐Niobium Phosphide on Plasma‐Defect‐Engineered Carbon Support for High‐Performance Hydrogen Evolution (Small 43/2020)

Small ◽  
2020 ◽  
Vol 16 (43) ◽  
pp. 2070236
Author(s):  
Dongliang Chen ◽  
Zhenmiao Xu ◽  
Wei Chen ◽  
Guangliang Chen ◽  
Jun Huang ◽  
...  
Keyword(s):  
Hydrogen Evolution ◽  
High Performance ◽  
Carbon Support
Sign in / Sign up

Export Citation Format

Share Document