An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• biotherapeutics, drugs, and vaccines through the skin. A wide range of microneedle structure, design, geometry, and microneedle array densities is manufactured using different rapid prototyping and microfabrication technologies such as deep reactive ion etching (DRIE) [2], lithography [3], hot embossing [4], and

• injection moulding [61], wet chemical etching [75], reactive ion etching [2][76], hot embossing [4][5], laser drilling [77], lithography plus electroforming [78][79], drawing lithography [80][81], two-photon polymerization [5][82], and 3D printing [83][84]. To date, DRIE of silicon; micromoulding

• mask which must be compensated for in the pattern design. Anisotropic etching uses either EDP (ethylenediamine pyrocatechol), hydrazine-based solutions or, most commonly, potassium hydroxide solution. Deep reactive ion etching of silicon is an increasingly common process, performed in a low-pressure

Progress and innovation of nanostructured sulfur cathodes and metal-free anodes for room-temperature Na–S batteries

• Marina Tabuyo-Martínez,
• Bernd Wicklein and
• Pilar Aranda

Beilstein J. Nanotechnol. 2021, 12, 995–1020, doi:10.3762/bjnano.12.75

• systems, but the current lithium-ion battery technology may face limitations in the future concerning the availability of raw materials and socio-economic insecurities. Sodium–sulfur (Na–S) batteries are a promising alternative energy storage device for small- to large-scale applications driven by more

• , lithium-ion batteries (LiBs) are undoubtedly the most important mobile electrical energy storage devices. Nevertheless, they have some critical limitations such as high cost, low resource availability, as well as access and safety concerns [1][5][6]. Therefore, new promising batteries based on widely

• available anode and cathode materials are sought. Table 1 lists some abundant metals as anode materials with high capacity and reduction potential values that are explored in metal-ion batteries [7][8][9]. Besides sodium as alternative anode material, also sulfur as abundant cathode material has emerged due

A Au/CuNiCoS₄/p-Si photodiode: electrical and morphological characterization

• Adem Koçyiğit,
• Adem Sarılmaz,
• Teoman Öztürk,
• Faruk Ozel and
• Murat Yıldırım

Beilstein J. Nanotechnol. 2021, 12, 984–994, doi:10.3762/bjnano.12.74

• great attention due their unique electronic, magnetic, optical, and gas sensing properties. Spinel compounds can be employed in data storage applications, lithium-ion batteries, gas sensors, and medical diagnostics [1][2]. Spinels have a cubic crystal structure with the general chemical formula AB2X4

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

• commonly used approach is the focused ion beam (FIB) polishing. Unfortunately, artefacts that can be easily induced by Ga FIB polishing approaches are seldom published. This work aims to provide a better understanding of the underlying causes for artefact formation and to assess if the helium ion

• microscope is better suited to achieve the required mirror-flat sample surface when operating the ion source with Ne instead of He. Copper was chosen as a test material and polished using Ga and Ne ions with different ion energies as well as incident angles. The results show that crystal structure

• interaction volume, a steady-state condition of ion impurity concentration and number of induced defects is reached. The EBSD measurements and Monte Carlo simulations indicate that when this steady-state condition is reached more quickly, which can be achieved using high-energy Ne ions at a glancing incidence

Uniform arrays of gold nanoelectrodes with tuneable recess depth

• Elena O. Gordeeva,
• Ilya V. Roslyakov,
• Alexey P. Leontiev,
• Alexey A. Klimenko and
• Kirill S. Napolskii

Beilstein J. Nanotechnol. 2021, 12, 957–964, doi:10.3762/bjnano.12.72

• direct-writing using electron beam lithography [11][12] or ion beam milling [13][14]) are limited by the ensemble area and expensive in mass production, but allow one to precisely tune the parameters of an array (a geometry of individual electrodes and the distance between them) over a wide range. An

• mechanical polishing or ion etching and subsequent re-deposition of the current collector. It is worth noting that a great number of Au electrodes within the array is extremely important for a practical application of NEAs under the kinetic control of a target electrochemical process. In this case, the

In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures

• Olena M. Kapran,
• Roman Morari,
• Taras Golod,
• Evgenii A. Borodianskyi,
• Vladimir Boian,
• Andrei Prepelita,
• Nikolay Klenov,
• Anatoli S. Sidorenko and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68

• were used for the calibration of the etching rates of the films. MLs are patterned into micrometer-scale bridges with multiple contacts using photolithography and reactive ion etching. A scanning electron microscopy (SEM) image of one of the studied samples is shown in Figure 1a. Control of the

Modification of a SERS-active Ag surface to promote adsorption of charged analytes: effect of Cu²⁺ ions

• Bahdan V. Ranishenka,
• Andrei Yu. Panarin,
• Irina A. Chelnokova,
• Sergei N. Terekhov,
• Peter Mojzes and
• Vadim V. Shmanai

Beilstein J. Nanotechnol. 2021, 12, 902–912, doi:10.3762/bjnano.12.67

• inversion. This is a key factor for the oligonucleotide detection with Cu2+-modified SERS substrates. The spectrum detection after Cu2+ treatment, followed by washing (which was not working for CuTSPP4), supports that and can be explained by a low Cu2+ ion concentration created by a residual PEI–copper

• microscope in PeakForceQNM mode with recording the adhesion force maps and topographic images. SERS measurements were carried out by using a scanning probe Raman microscope “NanoFlex” (Solar LS, Belarus). The source of excitation at 488.0 nm was an argon ion laser (Melles Griot, USA). Excitation and

• ) were used as a probe analyte. The solutions were drop-cast onto the substrate (ca. 100 µL/cm2), and dried at room temperature. In the case of metal ion addition, 5 mM of the corresponding sulfate was added to the analyte solution. SERS acquisitions parameters The SERS spectra were obtained in back

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

• specific ion channel blockers. They concluded that the simultaneous entry of Ca2+ ions is an indication that the acoustic pressure leads to diffusion of Ca2+ ions through the cell membrane pores [204]. The fact that the intracellular Ca2+ ion concentration depends on the extracellular Ca2+ ion

Silver nanoparticles nucleated in NaOH-treated halloysite: a potential antimicrobial material

• Yuri B. Matos,
• Rodrigo S. Romanus,
• Mattheus Torquato,
• Edgar H. de Souza,
• Rodrigo L. Villanova,
• Marlene Soares and
• Emilson R. Viana

Beilstein J. Nanotechnol. 2021, 12, 798–807, doi:10.3762/bjnano.12.63

• of the top ten threats to public health [1]. Antimicrobial nanomaterials are one of the most promising antibiotic-free alternatives for many applications. Among them are metallic nanoparticles, which could be potent inorganic antimicrobial agents through ion release and the capability to rupture the

Recent progress in actuation technologies of micro/nanorobots

• Ke Xu and
• Bing Liu

Beilstein J. Nanotechnol. 2021, 12, 756–765, doi:10.3762/bjnano.12.59

• towards the platinum end, and a maximum movement speed of 4 μm/s was achieved. After that, Chen et al. [40] designed a Z-shaped platinum hybrid nanorobot in order to meet the growing demand for micro/nanorobots in the biomedical field. It was manufactured using a combination of focused ion beam and plasma

Nanogenerator-based self-powered sensors for data collection

• Yicheng Shao,
• Maoliang Shen,
• Yuankai Zhou,
• Xin Cui,
• Lijie Li and
• Yan Zhang

Beilstein J. Nanotechnol. 2021, 12, 680–693, doi:10.3762/bjnano.12.54

• hydrological data such as wave information [12][13], water quality [14][15], and ion concentration [16][17][71], which can be used for weather forecasting, disaster warning, and water quality protection. In addition, long-term monitoring and collection of hydrological data can also provide a certain reference

• . Lee et al. proposed a based Hg2+ ion sensor based on ZnO nanowires and carbon nanotubes for detecting toxic pollutants [17]. The ZnO nanowire (NW) array acted as power source. When Hg2+ ions were detected, the system powered a light-emitting diode (LED). Li et al. designed a self-powered heavy metal

• ion triboelectric nanosensor [16]. By adding three ligand molecules to the surface of nanoporous anodic aluminum oxide, the detection sensitivity for Cu2+, Pb2+, and Cr3+ reached 0.005 × 10−6, 0.003 × 10−6, and 0.004 × 10−6 M, respectively. The self-powered tribo-nanosensor generates different output

Fate and transformation of silver nanoparticles in different biological conditions

• Barbara Pem,
• Marija Ćurlin,
• Darija Domazet Jurašin,
• Valerije Vrček,
• Rinea Barbir,
• Vedran Micek,
• Raluca M. Fratila,
• Jesus M. de la Fuente and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2021, 12, 665–679, doi:10.3762/bjnano.12.53

• association of Ag with sulphur and the formation of Ag2S granules from ion exchange or Ag–thiol complexes is known as sulphidation [28][29]. However, many other scenarios should be considered during an in vivo journey of AgNPs and Ag+ ions, especially their interactions with biomolecules, such as lipids

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• Frances I. Allen Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, USA 10.3762/bjnano.12.52 Abstract The helium ion microscope has emerged as a

• multifaceted instrument enabling a broad range of applications beyond imaging in which the finely focused helium ion beam is used for a variety of defect engineering, ion implantation, and nanofabrication tasks. Operation of the ion source with neon has extended the reach of this technology even further. This

• paper reviews the materials modification research that has been enabled by the helium ion microscope since its commercialization in 2007, ranging from fundamental studies of beam–sample effects, to the prototyping of new devices with features in the sub-10 nm domain. Keywords: defect engineering

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• acquisition. Sample preparation: A Cu(111) single crystal (MaTeck GmbH) is cleaned via repeated cycles of Ar-ion sputtering at room temperature followed by annealing to 1020 K in an ultrahigh-vacuum preparation chamber. A partial layer of h-BN is grown by chemical vapour deposition by heating the Cu(111

Influence of electrospray deposition on C₆₀ molecular assemblies

• Antoine Hinaut,
• Sebastian Scherb,
• Sara Freund,
• Zhao Liu,
• Thilo Glatzel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2021, 12, 552–558, doi:10.3762/bjnano.12.45

• are visible, see the arrow in the contrast-modified inset of Figure 3c and in part 3 of Supporting Information File 1. They are similar to the pits created after electron and ion bombardment [40][41][42][43] or low-temperature plasma exposure of such a surface [44]. Such defects are known to increase

The preparation temperature influences the physicochemical nature and activity of nanoceria

• Robert A. Yokel,
• Wendel Wohlleben,
• Johannes Georg Keller,
• Matthew L. Hancock,
• Jason M. Unrine,
• D. Allan Butterfield and
• Eric A. Grulke

Beilstein J. Nanotechnol. 2021, 12, 525–540, doi:10.3762/bjnano.12.43

• . Nanoceria dissolution releases Ce3+ ions, which, with phosphate, form insoluble cerium phosphate in vivo. The addition of immobilized phosphates did not accelerate nanoceria dissolution, suggesting that the Ce3+ ion release during nanoceria dissolution was phosphate-independent. Smaller particles resulting

• dissolution rate (Table 2), as previously reported [39][40]. The rate of NM-212 dissolution was much slower (Figure 8 and Table 2). High-temperature exposure greatly decreased the dissolution of the solvothermally synthesized nanoceria (Figure 9). Cerium ion complexation and nanoceria dissolution in the

• +, consistent with the interpretation that nanoceria dissolution occurs at the solid–liquid interface [14]. Cerium ions may then complex with phosphate. Nanoceria dissolution is pH-dependent ([14][39][70] and Figure 11). Nanoceria dissolution presumably results from an interaction between the hydrogen ion and

Simulation of gas sensing with a triboelectric nanogenerator

• Kaiqin Zhao,
• Hua Gan,
• Huan Li,
• Ziyu Liu and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2021, 12, 507–516, doi:10.3762/bjnano.12.41

• ], single electrode mode [32][33][34], and independent layer mode [35]. In order to explain the charge transfer process between two friction materials in contact, various models have been proposed and explored, such as electron cloud model [36][37][38], ion transfer model [39], and material transfer model

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• enhanced by the mobility decrease in the nearest vicinity of the metal nanoparticle and by the increase of the rotational relaxation time and residence time of water molecules surrounding the ion wall in a charged monolayer-protected Au nanoparticle [39]. Assuming that the observed Raman enhancement is

Interface interaction of transition metal phthalocyanines with strontium titanate (100)

• Reimer Karstens,
• Thomas Chassé and
• Heiko Peisert

Beilstein J. Nanotechnol. 2021, 12, 485–496, doi:10.3762/bjnano.12.39

• × 10 × 0.5 mm3, 0.5 wt % Nb). The surfaces were typically prepared in vacuo by repeated cycles of Ar ion sputtering (0.5 kV, p(Ar) = 5 × 10−5 mbar, 30 min) and annealing (900 K, p(O2) = 4 × 10−5 mbar, 30 min). This method is called “preparation I” in the following. We note that this procedure results

• oxygen atmosphere (p(O2) = 4 × 10−5 mbar) at a substrate temperature of 910 K. The Ti thickness was monitored by the ion flux of the electron beam evaporator (EFM 3s, Focus GmbH) calibrated by a quartz microbalance. The estimation of the TiO2 thickness from the attenuation of the Sr 3d peak intensity

• components in the N 1s and C 1s spectra are accompanied by satellite components at 1.6–1.8 eV higher binding energy (SN, SC-1, and SC-2). The shape of the Co 2p3/2 spectrum is characterized by complex multiplet structures of the Co(II) ion with d7 electron configuration [39][55][57][58]. The monolayer

A review on nanostructured silver as a basic ingredient in medicine: physicochemical parameters and characterization

• Gabriel M. Misirli,
• Kishore Sridharan and
• Shirley M. P. Abrantes

Beilstein J. Nanotechnol. 2021, 12, 440–461, doi:10.3762/bjnano.12.36

• prominent {111} facets. In addition to prioritizing the characterization we have also discussed the importance of quantifying AgNPs and silver ion content (Ag+) and their different mechanisms at the chemical, biological, pharmacological, and toxicological levels. The mechanism of action of AgNPs against

• studies of this promising agent in nanomedicine and in clinical practice. Keywords: bactericidal agent; {111} facets; mechanism of action; silver ion; silver nanoparticles; quality control; virucidal agent; Review Introduction Silver is one of the oldest bactericidal agents in history and is also

• , and toxicological levels, the identification and quantification of AgNP species as well as the silver ion (Ag+) content should be considered, as their behaviors and mechanisms are distinct [59][60]. Although the Ag+ ion has antimicrobial properties (such as AgNPs), it is rated as one of the main

Solution combustion synthesis of a nanometer-scale Co₃O₄ anode material for Li-ion batteries

• Monika Michalska,
• Huajun Xu,
• Qingmin Shan,
• Shiqiang Zhang,
• Yohan Dall'Agnese,
• Yu Gao,
• Amrita Jain and
• Marcin Krajewski

Beilstein J. Nanotechnol. 2021, 12, 424–431, doi:10.3762/bjnano.12.34

• obtained material was composed of loosely arranged nanoparticles whose average diameter was about 36 nm. The as-prepared cobalt oxide powder was also tested as the anode material for Li-ion batteries and revealed specific capacities of 1060 and 533 mAh·g−1 after 100 cycles at charge–discharge current

• current densities between 50 and 5000 mA·g−1. Keywords: anode material; cobalt oxide; lithium-ion battery; solution combustion synthesis; transition metal oxide; Introduction Recently, a considerable research effort regarding new anode materials has been made because the traditional carbonaceous anodes

• cannot meet the requirements of the next-generation lithium-ion batteries (LiBs) due to their low capacity, sensitivity to electrolyte, and limited capability [1][2][3]. As a result, plenty of materials with high capacity and rate capability, good recyclability, and long lifetime have been proposed as

Colloidal particle aggregation: mechanism of assembly studied via constructal theory modeling

• Scott C. Bukosky,
• Sukrith Dev,
• Monica S. Allen and
• Jeffery W. Allen

Beilstein J. Nanotechnol. 2021, 12, 413–423, doi:10.3762/bjnano.12.33

• electrolyte ions arrange near the surface of the particles to form an electric double layer, thus screening the surface charge. The characteristic length or “thickness” of this double layer (which is a function of the ion concentration, I) is known as the Debye length, λD, while the surface charge is

Spontaneous shape transition of Mn_xGe_1−x islands to long nanowires

• S. Javad Rezvani,
• Luc Favre,
• Gabriele Giuli,
• Yiming Wubulikasimu,
• Isabelle Berbezier,
• Augusto Marcelli,
• Luca Boarino and
• Nicola Pinto

Beilstein J. Nanotechnol. 2021, 12, 366–374, doi:10.3762/bjnano.12.30

• and 25 mA with a graphite monochromator. Step-scan diffractograms were collected in the 2θ range of 3–70° with 0.02° step and 3 s/step counting time. For HRTEM analysis, focused ion beam (FIB) lamellae were prepared using a dual-beam FIB. The lamellae were oriented along the elongation direction. The

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

• Petronela Prepelita,
• Florin Garoi and
• Valentin Craciun

Beilstein J. Nanotechnol. 2021, 12, 354–365, doi:10.3762/bjnano.12.29

• -frequency magnetron sputtering (rfMS) [27][28][29][30], vacuum thermal evaporation (VTE) [31][32][33], chemical methods [34], reactive ion beam sputter deposition [35], among others. For example, SiO2 and ZnO films obtained by rfMS can be either used as dielectric materials in metasurface structures or as

• XPS measurements of the analyzed samples were performed with photons that cause no major disturbances on the bombarded surface. To keep the contamination layer from the surface of the films, they were not sputtered using the ion gun. This is because sometimes the sputtering affects the stoichiometry

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• was carried out by 1H and 13C NMR. Quantitative anion exchange and IL purity of 99.9% was assessed by ion chromatography (Dionex ICS-1100, with IonPac® AS22, 4 × 250 mm column). The water content, measured by coulometric Karl Fischer titration, was below 10 ppm. rGO was synthesized in a two-step