Five types of conjugated phenylene polymer-modified photoanodes for quantum dot-sensitized solar cells (QDSSCs) were prepared by immobilization of CdSe QDs after electrochemical polymerization of functionalized phenyldiazonium salts onto ITO glass electrodes. The successful preparation of the conjugated phenylene polymer-modified photoanodes for QDSSCs was confirmed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), FT-IR spectroscopy, UV-visible spectroscopy, contact angles, and electrochemical impedance spectroscopy. The open-circuit voltage and fill factor in QDSSCs with the conjugated phenylene polymer with -COOH photoanodes were achieved at 0.52&#x2009;V and 76.8&#x25;, respectively, and the energy conversion efficiency was improved to 2.73&#x25; using the conjugated phenylene polymer with -COOH photoanodes.

So-Ra Lee

Da-Seul Kim

Seong-Ho Choi

The Conjugated Phenylene Polymer-Modified Photoanodes for Quantum Dot-Sensitized Solar Cells

ZnS:Mn nanocrystals thin film was fabricated at 300&#xb0;C and 500&#xb0;C via the spin coating method. Its sol-gel was spin coated for 20&#x2009;s at 3000&#x2009;rpm and 4000&#x2009;rpm with metal tape being used to mold the shape of the thin film. A different combination of these parameters was used to investigate their influences on the fabrication of the film. Optical and structural characterizations have been performed. Optical characterization was analyzed using UV-visible spectroscopy and photoluminescence spectrophotometer while the structural and compositional analysis of films was measured via field emission scanning electron microscopy and energy dispersive X-ray. From UV-vis spectra, the wavelength of the ZnS:Mn was 250&#x2009;nm and the band gap was within the range 4.43&#x2009;eV&#x2013;4.60&#x2009;eV. In room temperature PL spectra, there were two emission peaks centered at 460&#x2009;nm and 590&#x2009;nm. Under higher annealing temperature and higher speed used in spin coating, an increase of 0.05&#x2009;eV was observed. It was concluded that the spin coating process is able to synthesize high quality spherical ZnS:Mn nanocrystals. This conventional process can replace other high technology methods due to its synthesis cost.

Noor Azie Azura Mohd Arif

Chong Chee Jiun

Sahbudin Shaari

Effect of Annealing Temperature and Spin Coating Speed on Mn-Doped ZnS Nanocrystals Thin Film by Spin Coating

Since O’Regan and Grätzel’s first report in 1991, dye-sensitized solar cells (DSSCs) appeared immediately as a promising low-cost photovoltaic technology. In fact, though being far less efficient than conventional silicon-based photovoltaics (being the maximum, lab scale prototype reported efficiency around 13%), the simple design of the device and the absence of the strict and expensive manufacturing processes needed for conventional photovoltaics make them attractive in small-power applications especially in low-light conditions, where they outperform their silicon counterparts. Nanomaterials are at the very heart of DSSC, as the success of its design is due to the use of nanostructures at both the anode and the cathode. In this review, we present the state of the art for both <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063904pt" id="M1" height="6.1673pt" version="1.1" viewBox="-0.0498162 -5.96091 6.6501 6.1673" width="6.6501pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-111" d="M495 86L479 114C446 82 419 66 409 66C401 66 401 72 406 97C420 166 436 231 453 297C489 435 454 448 428 448C406 448 384 439 354 422C305 394 222 327 161 247H159L183 345C200 415 194 448 173 448C143 448 82 410 23 351L38 325C64 349 95 371 105 371C111 371 116 365 109 336L25 -4L31 -12C50 -4 77 3 107 9C119 69 132 122 145 168C197 254 321 381 370 381C387 381 393 374 378 305L329 95C309 17 320 -12 345 -12C372 -12 430 19 495 86Z"/></g></svg>-type and <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.42943pt" id="M2" height="10.2124pt" version="1.1" viewBox="-0.0498162 -6.78297 7.83752 10.2124" width="7.83752pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-113" d="M570 304C570 398 525 448 414 448C385 448 343 445 312 434L329 511L321 518C297 504 262 482 244 460L233 411C195 397 159 381 128 358L135 332C160 347 189 360 224 373L111 -147C97 -210 84 -218 17 -231L13 -257L254 -247L259 -218L233 -216C183 -212 177 -202 189 -142L218 -1C238 -10 266 -12 283 -12C351 3 429 48 483 105C543 168 570 242 570 304ZM482 289C482 161 380 33 304 33C278 33 248 51 233 69L303 396C326 400 352 403 369 403C428 403 482 380 482 289Z"/></g></svg>-type semiconductors used in the photoelectrodes of DSSCs, showing the evolution of the materials during the 25 years of history of this kind of devices. In the case of <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-3.42943pt" id="M3" height="10.2124pt" version="1.1" viewBox="-0.0498162 -6.78297 7.83752 10.2124" width="7.83752pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g113-113"/></g></svg>-type semiconductors, also some other energy conversion applications are touched upon.

Carmen Cavallo

Francesco Di Pascasio

Alessandro Latini

Matteo Bonomo

Danilo Dini

Nanostructured Semiconductor Materials for Dye-Sensitized Solar Cells

Carbon nanodots (CNDs) derived from a green precursor, kidney beans, was synthesized with high yield via a facile pyrolysis technique. The CND material was easily modified through simple oxidative treatment with nitric acid, leading to a high density &#x201c;self-passivated&#x201d; water soluble form (wsCNDs). The synthesized wsCNDs have been extensively characterized by using various microscopic and spectroscopic techniques and were crystalline in nature. The highly carboxylated wsCNDs possessed tunable-photoluminescence emission behavior throughout the visible region of the spectrum, demonstrating their application for multicolor cellular imaging of HeLa cells. The tunable-photoluminescence properties of &#x201c;self-passivated&#x201d; wsCNDs make them a promising candidate as a probe in biological cell-imaging applications.

Kumud Malika Tripathi

Tuan Sang Tran

Tran Thanh Tung

Dusan Losic

TaeYoung Kim

Water Soluble Fluorescent Carbon Nanodots from Biosource for Cells Imaging

In this study, we describe the design, synthesis, and physicochemical and preliminary biological characteristics of new biodegradable, high-molecular-weight (HMW) drug delivery systems with star-like architectures bearing the cytotoxic drug doxorubicin (DOX) attached by a hydrazone bond-containing spacer. The star polymers were synthesized by grafting semitelechelic N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers on a 2,2-bis(hydroxymethyl)propionic acid- (bis-MPA-) based polyester dendritic core. The molecular weight of the star polymers ranged from 280 to 450 000&#x2009;g/mol and could be adjusted by proper selection of the bis-MPA dendrimer generation and by considering the polymer to dendrimer molar ratio. The biodegradation of the polymer conjugates is based on the spontaneous slow hydrolysis of the dendritic core in neutral physiological conditions. Hydrazone spacers in the conjugates were fairly stable at neutral pH (7.4) mimicking blood stream conditions, and DOX was released from the conjugates under mild acidic conditions simulating the tumor cell microenvironment in endosomes and lysosomes (pH 5). Finally, we have shown the significant in vitro cytotoxicity of the star polymer-DOX conjugate on selected cancer cell lines with IC<sub>50</sub> values almost comparable with that of the free drug and higher than that observed for a linear polymer-DOX conjugate with much lower molecular weight.

H. Kostkov&#xe1;

L. Schindler

L. Kotrchov&#xe1;

M. Kov&#xe1;&#x159;

M. &#x160;&#xed;rov&#xe1;

L. Kostka

T. Etrych

Star Polymer-Drug Conjugates with pH-Controlled Drug Release and Carrier Degradation

In this work, a quick and effective method to synthesize carbon nanotubes (CNTs) is reported; a commercial microwave oven of 600&#x2009;W at 2.45&#x2009;GHz was utilized to synthesize CNTs from plasma catalytic decomposition of polyethylene. Polyethylene and silicon substrate coated with iron (III) nitrate were placed in the reaction chamber to form the synthesis stock. The CNTs were synthesized at 750&#xb0;C under atmospheric pressure of 0.81&#x2009;mbar. Raman spectroscopy and field emission scanning electron microscope revealed the quality and entangled bundles of mixed CNTs from which the diameters of the CNTs were calculated to be between 1.03 and 25.00&#x2009;nm. High resolution transmission electron microscope further showed that the CNTs obtained by this method are graphitized. Energy dispersive X-ray analysis and thermogravimetric analysis revealed above 98&#x25; carbon purity.

N. Kure

M. N. Hamidon

S. Azhari

N. S. Mamat

H. M. Yusoff

B. M. Isa

Z. Yunusa

Simple Microwave-Assisted Synthesis of Carbon Nanotubes Using Polyethylene as Carbon Precursor

The size effect of magnetomechanical response of chemically cross-linked disk shaped magnetic elastomers placed on a permanent magnet has been investigated by unidirectional compression tests. A cylindrical permanent magnet with a size of 35&#x2009;mm in diameter and 15&#x2009;mm in height was used to create the magnetic field. The magnetic field strength was approximately 420&#x2009;mT at the center of the upper surface of the magnet. The diameter of the magnetoelastic polymer disks was varied from 14&#x2009;mm to 35&#x2009;mm, whereas the height was kept constant (5&#x2009;mm) in the undeformed state. We have studied the influence of the disk diameter on the stress-strain behavior of the magnetoelastic in the presence and in the lack of magnetic field. It was found that the smallest magnetic elastomer with 14&#x2009;mm diameter did not exhibit measurable magnetomechanical response due to magnetic field. On the opposite, the magnetic elastomers with diameters larger than 30&#x2009;mm contracted in the direction parallel to the mechanical stress and largely elongated in the perpendicular direction. An explanation is put forward to interpret this size-dependent behavior by taking into account the nonuniform field distribution of magnetic field produced by the permanent magnet.

Tsubasa Oguro

Shuhei Sasaki

Yuri Tsujiei

Mika Kawai

Tetsu Mitsumata

Tatsuo Kaneko

Mikl&#xf3;s Zr&#xed;nyi

Sample Size Effect of Magnetomechanical Response for Magnetic Elastomers by Using Permanent Magnets

Ultrasonic Spray Pyrolysis (USP) possesses a great potential for production of higher quantities of gold nanoparticles (AuNPs), thus overcoming the problem of batch-to-batch variations in their properties. Recently, we demonstrated that USP with an additional evaporation chamber (modular USP) led to a better size control of AuNPs. However, their morphology, stability, toxicity, and immunomodulatory properties have not been investigated completely. Here, two types of spherical AuNPs were produced by using different USP parameters, followed by their stabilization in Na-citrate solution. No significant changes in their size, agglomeration, and <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.29774pt" id="M1" height="6.44133pt" version="1.1" viewBox="-0.0498162 -6.14359 6.59789 6.44133" width="6.59789pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g113-123" d="M475 445L452 468C423 436 401 426 385 426S352 427 305 436C268 443 216 448 185 448C156 448 128 425 102 382C89 360 77 338 64 304L89 291C117 340 143 380 190 380C214 380 268 376 295 373C320 370 344 371 362 374L70 101C32 65 23 36 23 18C23 5 27 -3 31 -8C36 -8 39 -6 42 -1C52 15 67 31 80 40S110 49 143 33C195 8 257 -20 290 -20C339 -20 382 11 439 129L416 148C366 74 334 55 305 55C278 55 236 68 203 81C169 94 141 100 122 96C205 170 348 308 411 376L475 445Z"/></g></svg>-potential occurred 3 months after their initial production in citrate solution. However, the conditioning of AuNPs in serum-containing cell culture media for 24 h induced an increase in the AuNPs’ hydrodynamic size and a red shift in their Surface Plasmon Resonance, pointing to their instability in biological media. Cytocompatibility tests showed that the produced AuNPs were internalized by L929 cells and primary human monocytes and were not cytotoxic at the concentrations lower than 200 <i>μ</i>g/mL, but they exhibited antiproliferative and anti-inflammatory effects, respectively. AuNPs reduced the percentage of CD14<sup>+</sup>CD16<sup>+</sup> but not CD14<sup>low</sup>CD16<sup>+</sup> monocytes in vitro and reduced the expression of CD86, HLA-DR, TNF-<i>α</i>, and IL-12/IL-23 by these cells. These results indicate that the anti-inflammatory effects of citrate-capped AuNPs produced by modular USP could be beneficial for their application in the treatment of inflammatory conditions.

Rebeka Rudolf

Peter Majeri&#x10d;

Sergej Tomi&#x107;

Mohammed Shariq

Urban Fer&#x10d;ec

Bojan Budi&#x10d;

Bernd Friedrich

Dragana Vu&#x10d;evi&#x107;

Miodrag &#x10c;oli&#x107;

Morphology, Aggregation Properties, Cytocompatibility, and Anti-Inflammatory Potential of Citrate-Stabilized AuNPs Prepared by Modular Ultrasonic Spray Pyrolysis

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<p><em>Journal of Nanomaterials</em> publishes research on nanoscale and nanostructured materials with an emphasis on synthesis, processing, characterization, and the applications of nanomaterials.</p>


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<p>Chief Editor Stefano Bellucci is Professor of Theoretical Physics at the National Institute for Nuclear Physics in Frascati, Italy. His research interests include&nbsp;nanoscience and nanotechnology, nanocarbon-based composites, and the biomedical applications of nanomaterials.</p>


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Journal of Nanomaterials - Table of contents 2017

title

Journal of Nanomaterials publishes research on nanoscale and nanostructured materials with an emphasis on synthesis, processing, characterization, and the applications of nanomaterials.

Journal of Nanomaterials