scholarly journals Temperature oscillations during photoinduced heating of aqueous suspensions of silicon nanoparticles

2021 ◽  
Vol 2058 (1) ◽  
pp. 012032
Author(s):  
V S Belov ◽  
E A Bobkov ◽  
V A Oleschenko ◽  
A V Kabashin ◽  
V Yu Timoshenko
Keyword(s):  
Laser Irradiation ◽  
Silicon Nanoparticles ◽  
Pulsation Frequency ◽  
Aqueous Suspensions ◽  
Local Overheating ◽  
Temperature Oscillations ◽  
Irradiation Power ◽  
Si Nanoparticles ◽  
Potential Applications ◽  
Surrounding Liquid

Abstract Temperature oscillations (pulsations) were detected in aqueous suspensions of silicon (Si) nanoparticles NPs under laser irradiation with highly absorbed light. The temperature pulsation frequency was found to depend on the NPs concentration in suspension and laser irradiation power. The observed phenomenon is assumed to be caused by the local overheating of Si NPs close to the boiling point of water, while the average heating of the surrounding liquid was insignificant. The observed phenomenon is discussed in view of potential applications in local photo-induced hyperthermia of cancer.

Laser Induced Oxidation Effects in Bismuth Thin Films

2012 ◽  
Vol 1477 ◽  
Author(s):  
Marco A. Zepeda ◽  
Michel Picquart ◽  
Emmanuel Haro-Poniatowski
Keyword(s):  
Thin Films ◽  
Raman Spectroscopy ◽  
Laser Irradiation ◽  
Raman Spectra ◽  
Exposure Time ◽  
Oxidation Process ◽  
Energy Dispersion Spectroscopy ◽  
Irradiation Power ◽  
Pure Bismuth ◽  
532 Nm

ABSTRACTThe Laser induced oxidation process of bismuth was investigated using Raman spectroscopy. Upon laser irradiation (λ = 532 nm) pure Bismuth was transformed gradually into Bi2O3. Raman spectra of the samples showed the characteristics peaks for pure Bi located at 71 cm-1 and 96 cm-1. The oxidation process was monitored by Raman spectra with four additional bands located at about 127 cm-1, 241 cm-1, 313 cm-1 and 455 cm-1. Maintaining constant the exposure time of irradiation, the intensity of these bands depended on laser irradiation power. The presence of Bi2O3 in the sample was confirmed through by energy dispersion spectroscopy (EDS).

scholarly journals Morphology engineering of silicon nanoparticles for better performance in Li-ion battery anodes

2020 ◽  
Vol 2 (11) ◽  
pp. 5335-5342 ◽  
Author(s):  
Samson Y. Lai ◽  
Jan Petter Mæhlen ◽  
Thomas J. Preston ◽  
Marte O. Skare ◽  
Marius U. Nagell ◽  
...  
Keyword(s):  
Silicon Nanoparticles ◽  
Li Ion Batteries ◽  
Li Ion Battery ◽  
Si Nanoparticles ◽  
Morphology Engineering ◽  
Li Ion

To demonstrate the influence of the origin of Si materials on their performance in Li-ion batteries, Si nanoparticles were synthesized via silane pyrolysis. We highlight the importance of morphology engineering for creating long-lasting materials for Li-ion batteries.

Encapsulating silicon nanoparticles into N-doped carbon film as a high-performance anode for lithium ion batteries

2018 ◽  
Vol 11 (04) ◽  
pp. 1850067 ◽  
Author(s):  
Zheng Xing ◽  
Chunlai Huang ◽  
Yichen Deng ◽  
Yulong Zhao ◽  
Zhicheng Ju
Keyword(s):  
Current Density ◽  
High Performance ◽  
Large Scale ◽  
Silicon Nanoparticles ◽  
Specific Capacity ◽  
Carbon Film ◽  
Lithium Ion ◽  
Fast Diffusion ◽  
Lithium Storage ◽  
Si Nanoparticles

A flexible strategy is to exploit encapsulating Si nanoparticles into N-doping carbon film (Si-NC) that can effectively localize the Si nanoparticles, thereby solving the problem of serious volume change during cycling as well as facilitating the fast diffusion of Li[Formula: see text], and thus achieving improved anode performance. A maximum capacity of 883.1[Formula: see text]mAh[Formula: see text]g[Formula: see text] at the current density of 100[Formula: see text]mA[Formula: see text]g[Formula: see text] after 50 charge and discharge processes is achieved for Si-NC. Even at a large current density of 2000[Formula: see text]mA[Formula: see text]g[Formula: see text], a specific capacity of 415[Formula: see text]mAh[Formula: see text]g[Formula: see text] is maintained. Moreover, the charge capacity can still almost recover the initial capacity as the current density is reverted to 100[Formula: see text]mA[Formula: see text]g[Formula: see text], indicating that Si-NC has a superior rate performance in lithium storage. This facile synthesis route provides a new perspective to produce Si/C composite at a low cost and large scale with good electrochemical performance.

Mechanisms of Visible Photoluminescence from Size-Controlled Silicon Nanoparticles

2002 ◽  
Vol 737 ◽  
Author(s):  
Toshiharu Makino ◽  
Nobuyasu Suzuki ◽  
Yuka Yamada ◽  
Takehito Yoshida ◽  
Ikurou Umezu ◽  
...  
Keyword(s):  
Silicon Nanoparticles ◽  
Localized States ◽  
Excitation Spectra ◽  
Excitation Process ◽  
Visible Photoluminescence ◽  
Peak Energy ◽  
Recombination Processes ◽  
Si Nanoparticles ◽  
Oxygen Gas ◽  
Size Controlled

ABSTRACTWe have observed visible photoluminescence (PL) spectra (peak energy: 3.1 eV) of size-controlled silicon (Si) nanoparticles annealed in oxygen gas. The PL peak energy did not depend on the temperature, and the PL lifetime was relatively fast (on the order of nanoseconds). It was inferred that the visible PL was attributed to localized states in the oxidized surfaces of size-controlled Si nanoparticles. We also observed the PL excitation spectra and studied the excitation process. In order to elucidate mechanisms of the visible PL, excitation and recombination processes are discussed.

Silicon nanoparticles embedded in a porous carbon matrix as a high-performance anode for lithium-ion batteries

2016 ◽  
Vol 4 (29) ◽  
pp. 11381-11387 ◽  
Author(s):  
Lili Wu ◽  
Juan Yang ◽  
Xiangyang Zhou ◽  
Manfang Zhang ◽  
Yongpeng Ren ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
Porous Carbon ◽  
High Performance ◽  
Silicon Nanoparticles ◽  
Reduction Process ◽  
Lithium Ion ◽  
Carbon Matrix ◽  
Magnesiothermic Reduction ◽  
Carbonization Process ◽  
Si Nanoparticles

Si nanoparticles embedded in a carbon matrix have been prepared by a carbonization process followed by a magnesiothermic reduction process.

Polyacrylonitrile-based turbostratic graphite-like carbon wrapped silicon nanoparticles: a new-type anode material for lithium ion battery

RSC Advances ◽  
2016 ◽  
Vol 6 (16) ◽  
pp. 12737-12743 ◽  
Author(s):  
Xiaozhong Dong ◽  
Chunxiang Lu ◽  
Liyong Wang ◽  
Pucha Zhou ◽  
Denghua Li ◽  
...  
Keyword(s):  
Lithium Ion Battery ◽  
Anode Material ◽  
Silicon Nanoparticles ◽  
Lithium Ion ◽  
Lithium Intercalation ◽  
Si Nanoparticles ◽  
New Type

The carbonaceous matrix formed by PAN-based turbostratic graphite-like carbon could give full play to the lithium-intercalation ability of Si nanoparticles.

scholarly journals Iodine and Selenium Biofortification of Chervil Plants Treated with Silicon Nanoparticles

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2528
Author(s):  
Nadezhda Golubkina ◽  
Anastasia Moldovan ◽  
Mikhail Fedotov ◽  
Helene Kekina ◽  
Viktor Kharchenko ◽  
...  
Keyword(s):  
Silicon Nanoparticles ◽  
Phenolic Content ◽  
Growth Stimulation ◽  
Complex Interaction ◽  
Shoot Biomass ◽  
Sodium Selenate ◽  
Plant Growth And Development ◽  
Joint Application ◽  
Si Nanoparticles ◽  
Total Antioxidant

Production of functional food with high levels of selenium (Se) and iodine (I) obtained via plant biofortification shows significant difficulties due to the complex interaction between the two elements. Taking into account the known beneficial effect of silicon (Si) on plant growth and development, single and joint foliar biofortification of chervil plants with potassium iodide (150 mg L−1) and sodium selenate (10 mg L−1) was carried out in a pot experiment with and without Si nanoparticles foliar supplementation. Compared to control plants, nano-Si (14 mg L−1) increased shoot biomass in all treatments: by 4.8 times with Si; by 2.8 times with I + Si; by 5.6 times with Se + Si; by 4.0 times with I + Se + Si. The correspondent increases in root biomass were 4.5, 8.7, 13.3 and 10.0 times, respectively. The growth stimulation effect of Se, I and I + Se treatments resulted in a 2.7, 3.5 and 3.6 times increase for chervil shoots and 1.6, 3.1 and 8.6 times for roots, respectively. Nano-Si improved I biofortification levels by twice, while I and Se enhanced the plant content of each other. All treatments decreased nitrate levels, compared to control, and increased the photopigment accumulation. Improvement of total antioxidant activity and phenolic content was recorded only under the joint application of Se + I + Si. Foliar nano-Si treatment affected other element content in plants: decreased Na+ accumulation in single and joint supplementation with Se and I, restored Fe, Mn and Cr amount compared to the decreased levels recorded in separately Se and I fortified plants and promoted Al accumulation both with or without Se and I biofortification. The results of this research suggest high prospects of foliar nano-Si supply for enhancing both growth and joint I/Se biofortification of chervil.

scholarly journals Ab Initio-Based Structural and Thermodynamic Aspects of the Electrochemical Lithiation of Silicon Nanoparticles

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 8 ◽  
Author(s):  
Seung-Eun Lee ◽  
Hyung-Kyu Lim ◽  
Sangheon Lee
Keyword(s):  
Atomistic Simulation ◽  
Silicon Nanoparticles ◽  
Crystalline Silicon ◽  
Silicon Nanoparticle ◽  
Maximum Capacity ◽  
Electrochemical Lithiation ◽  
Si Nanoparticles ◽  
Negative Effect ◽  
Thermodynamic Mechanism ◽  
New Si

We reported the theoretical understandings of the detailed structural and thermodynamic mechanism of the actual lithiation process of silicon nanoparticle systems based on atomistic simulation approaches. We found that the rearrangement of the Si bonding network is the key mechanism of the lithiation process, and that it is less frequently broken by lithiation in the smaller sizes of Si nanoparticles. The decreased lithiation ability of the Si nanoparticles results in the lithiation potential being significantly lower than that of crystalline silicon phases, which impedes the full usage of the theoretical maximum capacity. Thus, nanosized Si materials could have a negative effect on performance if they become too fine-sized. These findings provide a detailed view of the electrochemical lithiation process of silicon nanoparticles (Si NPs) and engineering guidelines for designing new Si-based nanostructured materials.

scholarly journals Near-Infrared Fluorescent Sorbitol Probe for Targeted Photothermal Cancer Therapy

Cancers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1286 ◽  
Author(s):  
Lee ◽  
Jung ◽  
Jo ◽  
Yang ◽  
Koh ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Laser Irradiation ◽  
Near Infrared ◽  
Photothermal Effect ◽  
Great Promise ◽  
Targeted Cancer Therapy ◽  
Potential Applications ◽  
Photothermal Property ◽  
Nir Laser

Abstract: Photothermal therapy (PTT) using a near-infrared (NIR) heptamethine cyanine fluorophore has emerged as an alternative strategy for targeted cancer therapy. NIR fluorophores showing a high molar extinction coefficient and low fluorescence quantum yield have considerable potential applications in photothermal cancer therapy. In this study, a bifunctional sorbitol–ZW800 conjugate was used as an advanced concept of photothermal therapeutic agents for in vivo cancer imaging and therapy owing to the high tumor targetability of the sorbitol moiety and excellent photothermal property of NIR heptamethine cyanine fluorophore. The sorbitol–ZW800 showed an excellent photothermal effect increased by 58.7 °C after NIR laser irradiation (1.1 W/cm2) for 5 min. The HT-29 tumors targeted by sorbitol–ZW800 showed a significant decrease in tumor volumes for 7 days after photothermal treatment. Therefore, combining the bifunctional sorbitol–ZW800 conjugate and NIR laser irradiation is an alternative way for targeted cancer therapy, and this approach holds great promise as a safe and highly efficient NIR photothermal agent for future clinical applications.

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