ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• large family of hexagonal layered ternary transition-metal carbides, carbonitrides, and nitrides with the formula: Mn+1AXn where M denotes a transition metal (Sc, Ti, V, Cr, Zr, Nb, Mo, Hf, or Ta), A denotes a group-13 or group-14 element (Al, Si, P, S, Ga, Ge, As, Cd, Ln, Sn, Tl, or Pb), and X denotes

• . synthesized large-scale 2D Mo2CTx from Mo2Ga2C powder by etching gallium (Ga) selectively with the aid of two etchants, hydrogen fluoride (HF) and lithium fluoride (LiF)/HCl, with subsequent delamination. The morphology of the developed flakes differed with the used etchant. After using LiF/HCl as etchant

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• imaging of insulating samples with nanoscale milling capabilities in one instrument. The milling efficiency can also be increased by the use of heavier ion species, such as Ne or Ga, where Ne is available for the standard He column, whereas Ga requires an additional column. In contrast to its success in

Piezotronic effect in AlGaN/AlN/GaN heterojunction nanowires used as a flexible strain sensor

• Jianqi Dong,
• Liang Chen,
• Yuqing Yang and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1847–1853, doi:10.3762/bjnano.11.166

• by MOCVD (Thomas Swan). Trimethylgallium (TMGa), trimethylaluminum (TMAl), and ammonia (NH3) were used as Ga, Al, and N sources, respectively. N2 and H2 were used as carrier gases in the growth process. A 1 μm layer of unintentionally doped GaN was deposited as the buffer layer on a sapphire

Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

• Nico Klingner,
• Gregor Hlawacek,
• Paul Mazarov,
• Wolfgang Pilz,
• Fabian Meyer and
• Lothar Bischoff

Beilstein J. Nanotechnol. 2020, 11, 1742–1749, doi:10.3762/bjnano.11.156

• ]. Currently, the majority of such instruments use a gallium liquid metal ion source (Ga-LMIS), but the demand in research as well as in the industry for other ion species is increasing permanently. Today, nearly half of the elements of the periodic table are demonstrated to be usable in FIB applications [2

• electronic drifts. In addition, gas bubble formation will not take place when Ga ions are used. To discuss the deviation between the simulated minimum milling width and the achieved trench widths in more detail, the experimental sputter beam profiles have been analyzed further. For HIM, the profiles of the

• multi-isotope LMAISs is a further factor of uncertainty that, in general, will worsen the achievable spatial resolution. Literature data for He and Ga are compiled in Figure 6. Normalized half profiles (ion beam radius) for helium beams averaged for different substrates (taken from [42][43]) and for 40

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• of the polymer. Effects of subsurface and surface processes on the surface morphology have been studied for three polymer materials: poly(methyl methacrylate), polycarbonate, and polydimethylsiloxane, by using focused ion beam irradiation with He+, Ne+, and Ga+. Thin films of a Pt60Pd40 alloy and of

• -plane features, at the nanoscale, of the pre-deposited films. Ion irradiation of the Au-coated samples results in delamination, bulging, and perforation of the Au film, which is attributed to the accumulation of gases from radiolysis at the film–substrate interface. The irradiation with Ne+ and Ga+ ions

• PMMA surface essentially intact and provides a new route to their out-of-plane patterning, which is interesting for a range of thin film applications. In the current work, we extend our study to the effects of the ion mass by irradiating PMMA substrates with He+, Ne+, and Ga+ ions, and to the role of

Triboelectric nanogenerator based on Teflon/vitamin B1 powder for self-powered humidity sensing

• Liangyi Zhang,
• Huan Li,
• Yiyuan Xie,
• Jing Guo and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2020, 11, 1394–1401, doi:10.3762/bjnano.11.123

• ]. Recently, TENG-based sensors have attracted increased attention [34][35][36][37][38][39][40][41]. In 2014, Ga-doped ZnO was used for the fabrication of piezo-humidity sensors with a high sensitivity and a fast response [42]. In 2018, Vivekananthan et al. proposed sustainable energy harvesting and battery

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• speculated a variety of origins for this defect, including a negatively charged As dopant [58], Si-vacancy hydrogen complexes [9], and B dopants [59][60]. Crystal vacancies have previously been identified in other materials using scanning probe microscopy including Ga vacancies in GaAs [61], As vacancies in

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• is based on Ga+ ions. Functional 3D nanomaterials have been grown by Ga+ FIBID in the last decade [21][22][23][24][25][26]. In particular, Ga+ FIBID in combination with W(CO)6 as precursor material yielded 3D superconducting W-based wires with a critical temperature (Tc) below 5 K and a critical

• magnetic field (µ0Hc2(0)) up to 9.5 T [14][15][16]. Alternatively, in combination with Nb(NMe2)3(N-t-Bu), Ga+ FIBID yielded NbC wires with a broadened Tc range from 4 to 11 K [18]. One significant limitation is that 3D elements below 100 nm in diameter cannot be obtained with Ga+ FIBID, mainly due to the

• relatively large Ga+ beam diameter (approx. 5 nm) and a high proximity effect generated by Ga+ ion scattering. Regarding a higher spatial resolution, the helium ion microscope (HIM) [27], based on a gas field-ionization source, has emerged as a tool for direct writing of complex 3D nano-objects taking

Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• at 1.32 eV is usually attributed to Si impurities at the Ga sites forming different complexes, such as (SiGaVGa) [28][29] or (SiGaGaAs) [30]. Since Si impurities exhibit an amphoteric behavior in GaAs, they give rise to an acceptor SiAs state in addition to the SiGa shallow donor state. The second PL

Effect of substitutional defects on resonant tunneling diodes based on armchair graphene and boron nitride nanoribbons lateral heterojunctions

• Majid Sanaeepur

Beilstein J. Nanotechnol. 2020, 11, 688–694, doi:10.3762/bjnano.11.56

• the semi-infinite contacts. The self-energy matrices are calculated through a highly convergent recursive method [39]. Then the transmission as a function of the energy is obtained via [39]: in which Ga(E) = (Gr(E))† is the advanced Green's function and Γj (j = 1, 2), represent the level broadening

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

• formation of PAA/PAH capsules via EDC crosslinking (Figure 3c) [26]. Similarly, the post crosslinking of PEI/PAA microcapsules via glutaraldehyde (GA) chemistry also resulted in better stability over a wide pH range [53]. These capsules successfully encapsulated dextran (2000 KDa) molecules without any

• as high as 910 MPa. By making use of the reaction between amine and aldehyde via GA chemistry, a single polymer PAH capsule can be fabricated [57]. The deposition of one PAH layer was followed by suspending the particles in GA solution to induce free aldehyde groups for deposition of the next PAH

• most commonly used method is the movement of cargo from lower to higher concentration via a concentration gradient based diffusion process such as in case of Dox loading in GA cross-linked (chitosan-alginate)5 microcapsules [76]. At low feeding concentrations (e.g., 750 µg/mL), the drug loading was

Influence of the epitaxial composition on N-face GaN KOH etch kinetics determined by ICP-OES

• Markus Tautz,
• Maren T. Kuchenbrod,
• Joachim Hertkorn,
• Robert Weinberger,
• Martin Welzel,
• Arno Pfitzner and
• David Díaz Díaz

Beilstein J. Nanotechnol. 2020, 11, 41–50, doi:10.3762/bjnano.11.4

• ]. Nucleation layers have the second but very important effect of controlling crystal orientation, which is commonly Ga-polar (0001) [7]. Other than nucleation layers, there are several more strategies for defect reduction. These all require the insertion of additional layers or layer transitions into the

• and a 2D GaN layer with a combined thickness of 2000 nm. A, C and E contained a rudimentary MQW to allow for photoluminescence microscopy (PLM) analysis of dislocation density. Wafer processing After growth with Ga-polarity, the Ga-face of epilayers were bonded to silicon carriers with a non-ohmic

• gas stream and 12 L min−1 cooling gas stream. The Ga concentration obtained was averaged from three separate subsequent measurements of the identical dilution. The maximum integration time was set to 15 s. Both low and high standard solutions were prepared with identical concentrations of pure KOH and

Air oxidation of sulfur mustard gas simulants using a pyrene-based metal–organic framework photocatalyst

• Ghada Ayoub,
• Mihails Arhangelskis,
• Xuan Zhang,
• Florencia Son,
• Timur Islamoglu,
• Tomislav Friščić and
• Omar K. Farha

Beilstein J. Nanotechnol. 2019, 10, 2422–2427, doi:10.3762/bjnano.10.232

• Award (for GA), and Northwestern University.

Design of a nanostructured mucoadhesive system containing curcumin for buccal application: from physicochemical to biological aspects

• Sabrina Barbosa de Souza Ferreira,
• Gustavo Braga,
• Évelin Lemos Oliveira,
• Jéssica Bassi da Silva,
• Hélen Cássia Rosseto,
• Lidiane Vizioli de Castro Hoshino,
• Mauro Luciano Baesso,
• Wilker Caetano,
• Craig Murdoch,
• Helen Elizabeth Colley and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2019, 10, 2304–2328, doi:10.3762/bjnano.10.222

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• -related conductance of pure monolayer zigzag and armchair BP devices. The transmission coefficient of a two-probe system can be calculated by, where GR and GA are the retarded and advanced non-equilibrium Green’s functions of the system, respectively, and ΓL and ΓR are the line-width functions describing

Synthesis of nickel/gallium nanoalloys using a dual-source approach in 1-alkyl-3-methylimidazole ionic liquids

• Ilka Simon,
• Julius Hornung,
• Juri Barthel,
• Jörg Thomas,
• Maik Finze,
• Roland A. Fischer and
• Christoph Janiak

Beilstein J. Nanotechnol. 2019, 10, 1754–1767, doi:10.3762/bjnano.10.171

• = 1,5-cyclooctadiene) and GaCp* (Cp* = pentamethylcyclopentadienyl) in the ionic liquid [BMIm][NTf2] selectively yields small intermetallic Ni/Ga nanocrystals of 5 ± 1 nm as derived from transmission electron microscopy (TEM) and high-angle annular dark-field scanning transmission electron microscopy

• experimentally [30][31] and reasoned by theory [32]. The phase diagram of Ni/Ga shows nine different Ni/Ga phases (Supporting Information File 1, Figure S1) [33][34][35][36]. In a comparison of the CO2 hydrogenation abilities of NiGa (β), Ni3Ga (α) and Ni5Ga3 (δ) high selectivities towards the formation of

• methanol were found for Ni5Ga3 and NiGa [37]. At 165 °C Ni5Ga3 (δ) yielded 100% selectivity towards methanol [38]. Above 220 °C Ni5Ga3 is even more active than a conventional Cu/ZnO/Al2O3 catalyst with less CO formation in the reverse water-gas shift reaction (rWGS). In Ni5Ga3 the Ga-rich step sites

Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• anchoring conditions from planar to vertical upon certain surface areas is performed using a FEI Scios dual-beam electron microscope operating with a FIB of Ga+ ions of a current of 0.1 nA accelerated by a voltage of 30 kV. The FIB patterning is controlled by digital templates, which prescribe the beam path

• within a raster consisting of up to 4096 × 3536 pixel2 as well as the time spent by the beam on each pixel (the so-called dwell time). According to our previous comparative study [31], a relatively small dose of Ga+ ions is sufficient for the required polymer transformation and we adopt here the same

Giant magnetoresistance ratio in a current-perpendicular-to-plane spin valve based on an inverse Heusler alloy Ti₂NiAl

• Yu Feng,
• Zhou Cui,
• Bo Wu,
• Jianwei Li,
• Hongkuan Yuan and
• Hong Chen

Beilstein J. Nanotechnol. 2019, 10, 1658–1665, doi:10.3762/bjnano.10.161

• transmission coefficient Tσ(E) can be calculated employing Tσ(E) = Tr[ГLGRГRGA], where ГL and ГR are the coupling matrix of the left and right electrode, respectively; GR and GA are the retarded and advanced Green’s function of the central region, respectively; and σ is the spin direction, spin up or spin down

Kelvin probe force microscopy of the nanoscale electrical surface potential barrier of metal/semiconductor interfaces in ambient atmosphere

• Petr Knotek,
• Tomáš Plecháček,
• Jan Smolík,
• Petr Kutálek,
• Filip Dvořák,
• Milan Vlček,
• Jiří Navrátil and
• Čestmír Drašar

Beilstein J. Nanotechnol. 2019, 10, 1401–1411, doi:10.3762/bjnano.10.138

• Republic (GA CR), projects No. 16-07711S and No. 19-11814S is greatly appreciated. The work was supported from European Regional Development Fund-Project "Modernization and upgrade of the CEMNAT (No. CZ.02.1.01/0.0/0.0/16_013/0001829)".

Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping

• Lukas Grünewald,
• Dagmar Gerthsen and
• Simon Hettler

Beilstein J. Nanotechnol. 2019, 10, 1290–1302, doi:10.3762/bjnano.10.128

• formation of holes in the film, which let us expect an offset thickness in the range of only a few nanometers. The fast generation of holes may be associated with the implantation depth of the impinging Ga ions (Figure 4d). When the film becomes thin enough for Ga ions to penetrate through, there is a

• penetration depth of the Ga ions in the material of the thin film. The thickness amplitude is smaller than expected, because even though the FIB is only scanned azimuthally along the minima, sputtering also takes place near the maxima of the sinusoidal structure and decreases the total thickness of the thin

• film with each repetition. Finer FIB probes at smaller FIB currents could improve this at the cost of increasing milling duration and possible artifacts due to stage drift. Furthermore, implanted Ga induces a dark contrast and alters the effective MIP compared to pristine aC. Since the FIB was only

Electroluminescence and current–voltage measurements of single-(In,Ga)N/GaN-nanowire light-emitting diodes in a nanowire ensemble

• David van Treeck,
• Johannes Ledig,
• Gregor Scholz,
• Jonas Lähnemann,
• Mattia Musolino,
• Abbes Tahraoui,
• Oliver Brandt,
• Andreas Waag,
• Henning Riechert and
• Lutz Geelhaar

Beilstein J. Nanotechnol. 2019, 10, 1177–1187, doi:10.3762/bjnano.10.117

• ) behavior of single, freestanding (In,Ga)N/GaN nanowire (NW) light-emitting diodes (LEDs) in an unprocessed, self-assembled ensemble grown by molecular beam epitaxy. The data were acquired in a scanning electron microscope equipped with a micromanipulator and a luminescence detection system. Single NW

• respective electroluminescence (EL) signal [6]. Yet another approach was implemented by Bavencove et al. and Musolino and co-workers [4][7]. They did not contact single (In,Ga)N/GaN NWs with a probe tip, but detected diffraction-limited EL spots in the working ensemble device using a confocal microscope

• epitaxy (MBE) on an n-doped Si(111) substrate. They consist of an intrinsic multiple quantum-well structure grown on a Si-doped n-GaN base of about 600 nm length. The active region is composed of four (In,Ga)N insertions with an In content of (20 ± 10)% and a thickness of 3 ± 1 nm. The insertions are

A highly efficient porous rod-like Ce-doped ZnO photocatalyst for the degradation of dye contaminants in water

• Binjing Hu,
• Qiang Sun,
• Chengyi Zuo,
• Yunxin Pei,
• Siwei Yang,
• Hui Zheng and
• Fangming Liu

Beilstein J. Nanotechnol. 2019, 10, 1157–1165, doi:10.3762/bjnano.10.115

• ]. In recent years, metal organic frameworks (MOFs) have been intensively investigated and widely utilized in various fields, such as electrocatalysis [14], heterogeneous catalysis [15] and photocatalysis [16]. Yang et al. [17] reported that Ga-MOF displayed moderate to high catalytic activity of

CuInSe₂ quantum dots grown by molecular beam epitaxy on amorphous SiO₂ surfaces

• Henrique Limborço,
• Pedro M.P. Salomé,
• Rodrigo Ribeiro-Andrade,
• Jennifer P. Teixeira,
• Nicoleta Nicoara,
• Kamal Abderrafi,
• Joaquim P. Leitão,
• Juan C. Gonzalez and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2019, 10, 1103–1111, doi:10.3762/bjnano.10.110

• , 20663 Casablanca, Morocco 10.3762/bjnano.10.110 Abstract The currently most efficient polycrystalline solar cells are based on the Cu(In,Ga)Se2 compound as a light absorption layer. However, in view of new concepts of nanostructured solar cells, CuInSe2 nanostructures are of high interest. In this work

• with the average size of the nanodots. Keywords: copper indium gallium selenide (CuInSe2); quantum dots; Introduction The chalcopyrite compound Cu(In,Ga)Se2 (CIGS) is used as the light absorber layer in thin film solar cells that typically consist of a glass substrate, a Mo back contact, the CIGS

• layer prior to the protective Pt bi-layer deposition assisted by electron and ion beams. The final polishing of the lamella was done using 1 keV in energy to reduce the lateral damage and the Ga implantation effects in the lamellae. EDS was performed in the same STEM microscope in order to check the [Cu

Electronic properties of several two dimensional halides from ab initio calculations

• Mohamed Barhoumi,
• Ali Abboud,
• Lamjed Debbichi,
• Moncef Said,
• Torbjörn Björkman,
• Dario Rocca and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2019, 10, 823–832, doi:10.3762/bjnano.10.82

• detailed electronic properties were not studied. In the present work, using density functional theory, we investigate the structural, vibrational and electronic properties of several 2D halide compounds such as the bromides (XOBr and X′FBr with X = Ac, Bi; X′ = Ba, Ca), the fluorides (XOF with X = Cr, Ga

• theory (DFPT) [40]. Results and Discussion In this section we discuss the structural and electronic properties of the compounds investigated in this paper. We will focus on XOBr and X′FBr (where X = Ac, Bi and X′ = Ba, Ca) for the bromides, on XOF (where X = Cr, Ga, In, La) for the fluorides, on XOCl and

• (where X = Cr, Ga, In, La) monolayers, as presented in Figure 4. For instance, we can see from the PDOS of AcOCl that the valence bands come from the Ac, O, and Cl atoms while the bottom of the conduction bands correspond mainly to states derived from the Ac atoms. The DOSs and PDOSs of the fluoride

Renewable energy conversion using nano- and microstructured materials

• Harry Mönig and
• Martina Schmid

Beilstein J. Nanotechnol. 2019, 10, 771–773, doi:10.3762/bjnano.10.76

• cells [1] or via microabsorbers as shown for Cu(In,Ga)Se2 [4] in this thematic issue. At the same time, material reduction demands for optical concepts that support efficient collection of the incident solar radiation. In this regard, nanotexturing is of interest, where optical resonances and light