Search results

Search for "porosity" in Full Text gives 219 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

  • Vadim Morari,
  • Aida Pantazi,
  • Nicolai Curmei,
  • Vitalie Postolache,
  • Emil V. Rusu,
  • Marius Enachescu,
  • Ion M. Tiginyanu and
  • Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

Graphical Abstract
  • amplitude of potential fluctuations is determined by the degree of doping and conductivity compensation. In porous semiconductors the amplitude is determined by the degree of porosity, while it is a function of local fluctuations of the composition in solid solutions, including ZnMgO. The observation of the
PDF
Album
Full Research Paper
Published 12 Jun 2020

A set of empirical equations describing the observed colours of metal–anodic aluminium oxide–Al nanostructures

  • Cristina V. Manzano,
  • Jakob J. Schwiedrzik,
  • Gerhard Bürki,
  • Laszlo Pethö,
  • Johann Michler and
  • Laetitia Philippe

Beilstein J. Nanotechnol. 2020, 11, 798–806, doi:10.3762/bjnano.11.64

Graphical Abstract
  • thickness and porosity of the nanostructures was determined, which describes a gamut of colours. The proposed mathematical model can be applied in different fields, such as wavelength absorbers, RGB (red, green, blue) display devices, as well as chemical or optical sensors. Keywords: anodic aluminium oxide
  • . In a previous study by our group, the effects of morphological parameters (pore diameters, interpore distance, porosity, and nanostructure order) on the colours and the effective refractive index of AAO films were studied on metal–AAO–Al nanostructures [4]. Thickness and porosity are the two main
  • design of colours by choosing a specific thickness [14]. Also, there is a model based on optical measurements (ellipsometry integrating indirectly thickness, porosity) in combination with total reflectance measurements to access the colours, in terms of L*a*b* values, of AAO–Al nanostructures filled with
PDF
Album
Supp Info
Full Research Paper
Published 13 May 2020

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

  • Secil Öztürk,
  • Yu-Xuan Xiao,
  • Dennis Dietrich,
  • Beatriz Giesen,
  • Juri Barthel,
  • Jie Ying,
  • Xiao-Yu Yang and
  • Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

Graphical Abstract
  • nitrogen-containing aromatic polymer frameworks with triazine rings, which exhibit high surface area, porosity, and thermal and chemical stability [21][22]. CTFs are promising materials for applications such as catalysts or catalyst support [23][24][25] and for energy storage and conversion [26][27][28
  • ]. CTFs can be synthesized through different methods and under different reaction conditions, which enables the control over porosity and surface area [29][30][31][32]. The nitrogen moieties within the CTFs can provide coordination anchors or support for metal species [33][34]. They allow for the
  • according to the literature by the ionothermal method [32][42]. Since the synthesis parameters, such as reaction temperature, affect texture, porosity and nitrogen content of the framework, two different reaction temperatures (400 and 600 °C) have been used for the synthesis (Scheme S1, Supporting
PDF
Album
Supp Info
Full Research Paper
Published 11 May 2020

Adsorptive removal of bulky dye molecules from water with mesoporous polyaniline-derived carbon

  • Hyung Jun An,
  • Jong Min Park,
  • Nazmul Abedin Khan and
  • Sung Hwa Jhung

Beilstein J. Nanotechnol. 2020, 11, 597–605, doi:10.3762/bjnano.11.47

Graphical Abstract
  • synthesis, high conductivity and nitrogen content. Porous carbon materials, with high porosity and nitrogen content, have also been obtained from PANI. In other words, functional carbon, for catalysts and supercapacitors can be derived from high temperature carbonization of PANI, especially in the co
  • JGB under a wide range of pH values (from 2 to 12). Results and Discussion Characterization of polyaniline-derived carbon (PDC) The porosity and pore size distribution of the adsorbents were characterized with nitrogen adsorption at 77 K. As shown in Figure 1a, the porosity of the PDC materials was
  • considerable when the pyrolysis temperature was equal to or higher than 700 °C. The detailed porosity data are summarized in Supporting Information File 1, Table S1. With increasing pyrolysis temperature up to 800 °C, the BET surface area, total pore volume and mesopore volume increased. However, all of the
PDF
Album
Supp Info
Full Research Paper
Published 08 Apr 2020

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

  • Matthias Simolka,
  • Hanno Kaess and
  • Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

Graphical Abstract
  • the coexistence of a lithiated and delithiated phase for LFP [78]. Additionally, other mechanisms and factors, e.g., the generation of surface layers, porosity and tortuosity of electrodes, electrolyte salts and concentration gradients in the electrodes are affecting the ion transport and therefore
PDF
Album
Supp Info
Full Research Paper
Published 07 Apr 2020

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

  • Varsha Sharma and
  • Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

Graphical Abstract
  • LbL multistep technique and can be easily controlled by varying the polymerization time. This single-step technique resulted in a wall thickness similar to the LbL multistep technique and was applicable to other particles of different size and porosity. Because of the broad absorption and interesting
PDF
Album
Review
Published 27 Mar 2020

Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions

  • Robert Kozioł,
  • Marcin Łapiński,
  • Paweł Syty,
  • Damian Koszelow,
  • Wojciech Sadowski,
  • Józef E. Sienkiewicz and
  • Barbara Kościelska

Beilstein J. Nanotechnol. 2020, 11, 494–507, doi:10.3762/bjnano.11.40

Graphical Abstract
  • , and thus the amplification of the electromagnetic field, was observed in several directions, depending on the direction of illumination. The plasmon resonance also has an effect on the porosity of the metallic nanostructures [26][27], which is why determining the shape and surface quality is extremely
PDF
Album
Full Research Paper
Published 25 Mar 2020

An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques

  • Felix M. Badaczewski,
  • Marc O. Loeh,
  • Torben Pfaff,
  • Dirk Wallacher,
  • Daniel Clemens and
  • Bernd M. Smarsly

Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23

Graphical Abstract
  • ][7][8]. The turbostratic microstructure of these “non-graphitic” carbon materials combined with variable conductivity and a significant nanoscale disordered porosity are typical features of this kind of carbon materials. Templating strategies are meanwhile well established to endow carbon materials
  • with defined porosity on the nanometer scale, in particular to enhance the surface area and to control the pore size [9][10][11][12]. This study is dedicated to a quantitative determination of the porosity, e.g., pore size, pore volume and pore shape of carbon materials prepared by hard-templating of
  • can markedly affect the nanoscale porosity [13][14][15][16][17][18][19][20][21]. Hence, a combined in-depth elucidation of meso/microporosity and the graphene-based structure upon heat treatment is pursued in this study to obtain a profound understanding of the relationship between the changes in the
PDF
Album
Supp Info
Correction
Full Research Paper
Published 10 Feb 2020

Facile biogenic fabrication of hydroxyapatite nanorods using cuttlefish bone and their bactericidal and biocompatibility study

  • Satheeshkumar Balu,
  • Manisha Vidyavathy Sundaradoss,
  • Swetha Andra and
  • Jaison Jeevanandam

Beilstein J. Nanotechnol. 2020, 11, 285–295, doi:10.3762/bjnano.11.21

Graphical Abstract
  • powder to prepare Hap is their cost effectiveness and ecologically friendly nature, high availability, enhanced interconnectivity, and biocompatibility [14]. Recently, it was reported that the bonding ability of the scaffold with surrounding tissues is determined by the porosity of the material and that
  • porosity and high surface-to-volume ratio when compared to spherical nanometer-sized Hap particles, which facilitates interconnectivity and improves targeted cell internalization efficiency [22]. Thus, the aim of the present work is to use a simple, facile, unique, safe and cost-effective precipitation
  • ]. However, the Hap NRs in the present work are nonporous as observed in the TEM images, which may affect the biocompatibility, while utilizing them as scaffolds. Hence, the calcination temperature must be optimized in the future studies to provide porosity in the Hap NRs to improving their biocompatibility
PDF
Album
Full Research Paper
Published 04 Feb 2020

High-performance asymmetric supercapacitor made of NiMoO4 nanorods@Co3O4 on a cellulose-based carbon aerogel

  • Meixia Wang,
  • Jing Zhang,
  • Xibin Yi,
  • Benxue Liu,
  • Xinfu Zhao and
  • Xiaochan Liu

Beilstein J. Nanotechnol. 2020, 11, 240–251, doi:10.3762/bjnano.11.18

Graphical Abstract
  • a capacitance retention of 84.1% after 2000 cycles [23]. Metal-organic frameworks (MOFs) with high porosity and tunable functionality are ideal sacrificial templates to synthesize metal oxides [24][25][26]. As a MOF derivative, Co3O4 derived from the zeolitic imidazolate framework-67 (ZIF-67) is
  • considered an ideal supporting material to hybridize with electroactive materials because of its low cost, easy fabrication, large surface area, interconnected porosity and high electrical conductivity [30][31]. Due to its micro/mesoporous 3D morphology with large open pores, it offers more space to grow
  • sample is characterized by a combination of type–IV and type–I isotherms, indicating the presence of micro- and mesopores with monolayer–multilayer adsorption. Furthermore, two distinct pore distribution curves are observed in the inset of Figure 5c revealing a hierarchical porosity: micro/mesopores
PDF
Album
Supp Info
Full Research Paper
Published 21 Jan 2020

Synthesis of amorphous and graphitized porous nitrogen-doped carbon spheres as oxygen reduction reaction catalysts

  • Maximilian Wassner,
  • Markus Eckardt,
  • Andreas Reyer,
  • Thomas Diemant,
  • Michael S. Elsaesser,
  • R. Jürgen Behm and
  • Nicola Hüsing

Beilstein J. Nanotechnol. 2020, 11, 1–15, doi:10.3762/bjnano.11.1

Graphical Abstract
  • doping on the carbon sphere morphology, structure, elemental composition, N bonding configuration as well as porosity is investigated in detail. For the N-doped carbon spheres, the maximum nitrogen content was found at a doping temperature of 700 °C, with a decrease of the N content for higher
  • microporosity of the materials is critical for an efficient ORR. Keywords: amorphous carbon; graphitized carbon; hydrothermal carbonization; nitridation; nitrogen doping; oxygen reduction reaction (ORR); porosity; Introduction Fuel cells and metal–air batteries are important renewable energy technologies
  • polypyrrole instead of ammonia resulted in pyridinic or pyrrolic N moieties, respectively [18]. Beside the N bonding configuration, the ORR activity is affected by the N content, the surface area (porosity) and possibly the degree of graphitization [27]. The nitrogen content defines, among others, the density
PDF
Album
Full Research Paper
Published 02 Jan 2020

Advanced hybrid nanomaterials

  • Andreas Taubert,
  • Fabrice Leroux,
  • Pierre Rabu and
  • Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

Graphical Abstract
  • yield diverse materials, which were found to depend on the P/Ti atom ratio [20]. The ratio was found to determine the particle size and the aggregation state and thereby could strongly tune the porosity of the resulting materials. Colloidal chemistry with patchy silica nanoparticles was employed to
PDF
Editorial
Published 20 Dec 2019

Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

  • Cynthia Kembuan,
  • Maysoon Saleh,
  • Bastian Rühle,
  • Ute Resch-Genger and
  • Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

Graphical Abstract
  • , is the coating of their surface with silica shells [22][23]. Additionally, optically transparent silica shells have many other advantages such as chemical inertness, high thermal stability, low cytotoxicity, high biocompatibility and tunable porosity [22][23][24]. An important parameter for all
PDF
Album
Supp Info
Full Research Paper
Published 09 Dec 2019

Four self-made free surface electrospinning devices for high-throughput preparation of high-quality nanofibers

  • Yue Fang and
  • Lan Xu

Beilstein J. Nanotechnol. 2019, 10, 2261–2274, doi:10.3762/bjnano.10.218

Graphical Abstract
  • their excellent properties, such as high surface-to-volume ratio and high porosity, nanomaterials have become more and more important in industrial manufacturing. As one of the most important methods for preparing nanomaterials, electrospinning (ES) [1][2][3] has received much attention [4][5][6][7
PDF
Album
Full Research Paper
Published 15 Nov 2019

Design and facile synthesis of defect-rich C-MoS2/rGO nanosheets for enhanced lithium–sulfur battery performance

  • Chengxiang Tian,
  • Juwei Wu,
  • Zheng Ma,
  • Bo Li,
  • Pengcheng Li,
  • Xiaotao Zu and
  • Xia Xiang

Beilstein J. Nanotechnol. 2019, 10, 2251–2260, doi:10.3762/bjnano.10.217

Graphical Abstract
  • composite with both large surface area and high porosity for the use as advanced electrode material in lithium–sulfur batteries. Double modified defect-rich MoS2 nanosheets are successfully prepared by introducing reduced graphene oxide (rGO) and amorphous carbon. The conductibility of the cathodes can be
PDF
Album
Supp Info
Full Research Paper
Published 14 Nov 2019

A novel all-fiber-based LiFePO4/Li4Ti5O12 battery with self-standing nanofiber membrane electrodes

  • Li-li Chen,
  • Hua Yang,
  • Mao-xiang Jing,
  • Chong Han,
  • Fei Chen,
  • Xin-yu Hu,
  • Wei-yong Yuan,
  • Shan-shan Yao and
  • Xiang-qian Shen

Beilstein J. Nanotechnol. 2019, 10, 2229–2237, doi:10.3762/bjnano.10.215

Graphical Abstract
  • effective method to prepare long-range continuous nanofibers. By controlling the spinning and sintering process, nanofiber membrane materials can be easily formed with high porosity and stable structure, especially continuous conductive networks can be formed, which are very suitable for self-standing
  • illustrates the effect of the 3D conductive network and the high porosity on electron and ion transport [40][41]. Figure 10 shows the rate performance of LiFePO4 and Li4Ti5O12 fiber membrane electrodes. Both electrodes can be charged and discharged normally from 0.5C to 10C. When the current density returns
  • porosity, stable structure, and the continuous conductive networks provide the electrodes with fast electronic and ionic transport paths [22][23][34][35]. This design and fabrication of all-fiber-based batteries provides a novel strategy for the development of advanced flexible lithium-ion batteries
PDF
Album
Supp Info
Full Research Paper
Published 13 Nov 2019

Ultrathin Ni1−xCoxS2 nanoflakes as high energy density electrode materials for asymmetric supercapacitors

  • Xiaoxiang Wang,
  • Teng Wang,
  • Rusen Zhou,
  • Lijuan Fan,
  • Shengli Zhang,
  • Feng Yu,
  • Tuquabo Tesfamichael,
  • Liwei Su and
  • Hongxia Wang

Beilstein J. Nanotechnol. 2019, 10, 2207–2216, doi:10.3762/bjnano.10.213

Graphical Abstract
  • were obtained for the Ni1.7Co1.3O4 material (Figure S4c, Supporting Information File 1). The relatively low surface area of the Ni1−xCoxS2 nanoflakes is ascribed to the filling with anions (SO32−, S−, OH−), the growth of primary nanoparticles with the subsequent reduction of porosity, which impedes
PDF
Album
Supp Info
Full Research Paper
Published 11 Nov 2019

Porous silver-coated pNIPAM-co-AAc hydrogel nanocapsules

  • William W. Bryan,
  • Riddhiman Medhi,
  • Maria D. Marquez,
  • Supparesk Rittikulsittichai,
  • Michael Tran and
  • T. Randall Lee

Beilstein J. Nanotechnol. 2019, 10, 1973–1982, doi:10.3762/bjnano.10.194

Graphical Abstract
  • -isopropylacrylamide (NIPAM) and acrylic acid (AAc). The hydrogel cores were then encased within either a porous or complete silver shell for which the localized surface plasmon resonance (LSPR) extends from visible to near-infrared (NIR) wavelengths (i.e., λmax varies from 550 to 1050 nm, depending on the porosity
  • with porosity. The porous silver nanocapsules exhibited extinction maxima in the visible spectral regions (λmax ≈ 550 nm with tailing into the NIR), while complete nanocapsules exhibited extinction maxima in the NIR spectral regions (λmax ≈ 950–1050 nm). The methods described in this study, detailing
PDF
Album
Full Research Paper
Published 04 Oct 2019

The influence of porosity on nanoparticle formation in hierarchical aluminophosphates

  • Matthew E. Potter,
  • Lauren N. Riley,
  • Alice E. Oakley,
  • Panashe M. Mhembere,
  • June Callison and
  • Robert Raja

Beilstein J. Nanotechnol. 2019, 10, 1952–1957, doi:10.3762/bjnano.10.191

Graphical Abstract
  • deposited on a traditional microporous aluminophosphate, with an analogous hierarchical species, containing both micropores and mesopores, we explore the influence of this dual porosity on nanoparticle deposition. We show that the presence of mesopores has limited influence on the nanoparticle properties
  • , but allows the system to maintain porosity after nanoparticle deposition. This will aid diffusion of reagents through the system, allowing continued access to the active sites in hierarchical systems, which offers significant potential in catalytic oxidation/reduction reactions. Keywords
  • : aluminophosphate; catalysis; hierarchical catalysts; nanoparticles; porosity; Findings The controlled synthetic design of metallic nanoparticles has generated significant interest in recent decades due to their implementation in a range of fields, including medicine [1], optics [2] and catalysis [3]. Given the
PDF
Album
Supp Info
Letter
Published 25 Sep 2019

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

  • Manuel Souto,
  • Joaquín Calbo,
  • Samuel Mañas-Valero,
  • Aron Walsh and
  • Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

Graphical Abstract
  • /bjnano.10.183 Abstract The design of metal–organic frameworks (MOFs) incorporating electroactive guest molecules in the pores has become a subject of great interest in order to obtain additional electrical functionalities within the framework while maintaining porosity. Understanding the charge-transfer
  • catalysis [3][4][5]. In addition, electroactive MOFs combining porosity and electrical conductivity [6][7][8] have also attracted much attention during the last years in view of their potential application, for example as chemiresistive sensors [9], field-effect transistors [10] or supercapacitors [11
  • electrical conductivity and porosity at the same time. Fullerenes (C60) [25] have found numerous applications in different fields, ranging from molecular electronics and nanotechnology to biomedical applications, due to their exceptional electrochemical and photophysical properties [26][27]. In particular
PDF
Album
Supp Info
Full Research Paper
Published 18 Sep 2019

Long-term entrapment and temperature-controlled-release of SF6 gas in metal–organic frameworks (MOFs)

  • Hana Bunzen,
  • Andreas Kalytta-Mewes,
  • Leo van Wüllen and
  • Dirk Volkmer

Beilstein J. Nanotechnol. 2019, 10, 1851–1859, doi:10.3762/bjnano.10.180

Graphical Abstract
  • frameworks (MOFs); sulfur hexafluoride; Introduction Metal–organic frameworks (MOFs) are coordination polymers with organic ligands containing (potential) voids [1]. Their porosity and high surface area make them attractive materials for adsorption-based applications [2][3][4][5]. MOFs have been suggested
PDF
Album
Supp Info
Full Research Paper
Published 10 Sep 2019

Processing nanoporous organic polymers in liquid amines

  • Jeehye Byun,
  • Damien Thirion and
  • Cafer T. Yavuz

Beilstein J. Nanotechnol. 2019, 10, 1844–1850, doi:10.3762/bjnano.10.179

Graphical Abstract
  • high porosity, which is beneficial for applications such as gas sorption, gas separation, heterogeneous (photo)catalysis, sensing, and (opto)electronics. However, the network structures are practically insoluble. Thus, the processing of nanoporous polymers into nanoparticles or films remains
  • . Keywords: film; liquid amine; nanoparticles; nanoporous polymer; processibility; Introduction Nanoporous polymers offer permanent porosity along with robust and light-weight frameworks. The building-block approach for nanoporous polymers allows for a nearly infinite variety of architectures by changing
  • chemistry and geometry of the monomers [1]. New discoveries on nanoporous polymers have been made based on different combinations of monomers yielding unique properties to the polymer structures. In particular, the high porosity of nanoporous polymers has gained significant attention in various applications
PDF
Album
Supp Info
Full Research Paper
Published 09 Sep 2019

The impact of crystal size and temperature on the adsorption-induced flexibility of the Zr-based metal–organic framework DUT-98

  • Simon Krause,
  • Volodymyr Bon,
  • Hongchu Du,
  • Rafal E. Dunin-Borkowski,
  • Ulrich Stoeck,
  • Irena Senkovska and
  • Stefan Kaskel

Beilstein J. Nanotechnol. 2019, 10, 1737–1744, doi:10.3762/bjnano.10.169

Graphical Abstract
  • a physical mixture of crystals exhibiting either op or cp phase and that these phases do not co-exist as domains within a single crystal. This supports the assumption that structural contraction is a cooperative phenomenon that propagates through the whole crystal. To further analyze the porosity
PDF
Album
Supp Info
Full Research Paper
Published 20 Aug 2019

TiO2/GO-coated functional separator to suppress polysulfide migration in lithium–sulfur batteries

  • Ning Liu,
  • Lu Wang,
  • Taizhe Tan,
  • Yan Zhao and
  • Yongguang Zhang

Beilstein J. Nanotechnol. 2019, 10, 1726–1736, doi:10.3762/bjnano.10.168

Graphical Abstract
  • composite. The BET specific surface area of the TiO2/GO composite was determined to be 155.2 m2 g−1. Through the Barrett–Joyner–Halenda (BJH) analysis, the pore size distribution of TiO2/GO shows that the majority of the pores are around 2.9 and 7.4 nm. The rich porosity not only provides abundant pore
PDF
Album
Full Research Paper
Published 19 Aug 2019

Upcycling of polyurethane waste by mechanochemistry: synthesis of N-doped porous carbon materials for supercapacitor applications

  • Christina Schneidermann,
  • Pascal Otto,
  • Desirée Leistenschneider,
  • Sven Grätz,
  • Claudia Eßbach and
  • Lars Borchardt

Beilstein J. Nanotechnol. 2019, 10, 1618–1627, doi:10.3762/bjnano.10.157

Graphical Abstract
  • and a total pore volume of up to 0.9 cm3·g−1. In order to generate different nitrogen contents and to increase the porosity of the carbon material, we used different ratios of urea and K2CO3. Moreover, the N-doped carbon materials have been investigated as electrode material for supercapacitors in
  • ., the reference with no K2CO3) does not show any porosity and a slightly decreased nitrogen content of 3.9 wt % compared to the pure PU-BM (5.7 wt %, Table 1). In contrast, a microporous material is obtained after adding only a small amount of K2CO3 (PUPC-800-1, Figure 2A) [69]. PUPC-800-1 exhibits a
  • have taken place. Since an equal ratio of PU and K2CO3 (PUPC-800-3) has yielded the highest porosity in the previous section, we kept the PU and K2CO3 ratio constant and added specific amounts of urea to investigate the influence of the nitrogen precursor on the nitrogen content and surface area
PDF
Album
Supp Info
Full Research Paper
Published 06 Aug 2019
Other Beilstein-Institut Open Science Activities