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Search for "vacancies" in Full Text gives 236 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.

Topographic signatures and manipulations of Fe atoms, CO molecules and NaCl islands on superconducting Pb(111)

  • Carl Drechsel,
  • Philipp D’Astolfo,
  • Jung-Ching Liu,
  • Thilo Glatzel,
  • Rémy Pawlak and
  • Ernst Meyer

Beilstein J. Nanotechnol. 2022, 13, 1–9, doi:10.3762/bjnano.13.1

Graphical Abstract
  • Cu(111) [62]. Occasionally, even a trilayer phase appears within the NaCl bilayer (Figure 3a and Figure 3b). Note also that dark protrusions originating from trapped Ar atoms are still visible through the NaCl island by STM as well as point defects. We do not exclude that these might be Cl vacancies
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Published 03 Jan 2022

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

  • Kerstin Neuhaus,
  • Christina Schmidt,
  • Liudmila Fischer,
  • Wilhelm Albert Meulenberg,
  • Ke Ran,
  • Joachim Mayer and
  • Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

Graphical Abstract
  • time dependence was shown to vary with dopant concentration (e.g., abundance of oxygen vacancies in ceria) and also depends on the ratio of grain boundary/grain bulk [22][23][24][25]. Single ceria grains in a mixed ion/electron-conductive composite have so far not been addressed by AFM-based
  • in this study strongly depended on the surrounding. In single-phase ceria materials, oxygen is incorporated into oxygen vacancies in the structure at high temperatures [4][30]: Previous studies showed that at temperatures below 400 °C the concentration of defect associates in ceria increases because
  • electrons are trapped at oxygen vacancy sites, allowing also for singly charged () or uncharged (VO) oxygen vacancies in close vicinity to Ce3+ ions [31][32], which show a strongly lowered mobility. For low temperatures, the common electroneutrality equation for acceptor-doped ceria can be shortened, as
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Published 15 Dec 2021

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

Graphical Abstract
  • , defects such as interstitials or vacancies can be created [23]. This can induce a significant amount of crystal structure alterations in a sample and thus artefacts. While these artefacts are well recognized for transmission electron microscopy (TEM) lamella preparation, in which the lamella preparation
  • produce artefacts that would compromise the TEM analysis. Monte Carlo simulations were performed using the program Stopping and Range of Ions in Matter (SRIM) to better understand the underpinning ion–solid interactions for the different settings [22]. The extent of created dislocations, vacancies as well
  • (Figure 2) obtained using SRIM shows that the interaction volume depth of the 30 keV Ga ions in Cu is ≈25 nm and is in the same range as the EBSD signal information depth of 20 nm. Throughout the interaction depth, 786 vacancies are created per incident ion while ten atoms are sputtered. The total number
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Published 31 Aug 2021

Prediction of Co and Ru nanocluster morphology on 2D MoS2 from interaction energies

  • Cara-Lena Nies and
  • Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

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  • Supporting Information File 1. A brief analysis of the magnetism of Co structures is given in section S5 of Supporting Information File 1. Adsorption of Co and Ru clusters on defective MoS2 It is well known from both theoretical and experimental studies, that the MoS2 ML easily forms S vacancies. To get a
  • adsorption. Using the formation of H2S from H2, we computed a vacancy formation energy of −6.16 eV, which confirms that defects are easily formed. Furthermore, our results showed that the presence of an S vacancy (giving a concentration of 2% vacancies per supercell) improved Cu adhesion and promoted the
  • S atom from the ML onto the Co structure to create a Co4S cluster, which was also the most favourable Co4 structure on the defective ML. This shows that, in the presence of Co, further vacancies can be formed through the transfer of S atoms onto the metal cluster. In contrast, the presence of the
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Published 14 Jul 2021

Electromigration-induced formation of percolating adsorbate islands during condensation from the gaseous phase: a computational study

  • Alina V. Dvornichenko,
  • Vasyl O. Kharchenko and
  • Dmitrii O. Kharchenko

Beilstein J. Nanotechnol. 2021, 12, 694–703, doi:10.3762/bjnano.12.55

Graphical Abstract
  • neighboring vacancies in the direction of electron flow leading to an accumulation of atoms at the anode and vacancies at the cathode [1][2]. Current trends in computer technology, namely, reducing the size of integrated circuits, increasing their power, and increasing the density of elements, have led to an
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Published 13 Jul 2021

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

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  • the introduction of lattice defects has been demonstrated in a variety of nanoengineering applications. The generation of vacancies, preferential sputtering of one atomic species over another, and the introduction of increasing amounts of disorder leading to eventual amorphization of a crystalline
  • . investigated the nature of the ion-induced defects further, and determined that after irradiation, the ion-induced vacancies become saturated with oxygen [20]. The authors of the latter thus proposed that the mechanism behind the irradiation-induced insulating behavior involved oxygen groups acting as charge
  • nitrogen, the focused helium ion beam was used to create lattice vacancies at predefined locations (in a similar manner to the related electron beam-based methods). After annealing to allow for diffusion of the vacancies, the presence of nitrogen-vacancy centers was confirmed by photoluminescence
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Published 02 Jul 2021

Impact of GaAs(100) surface preparation on EQE of AZO/Al2O3/p-GaAs photovoltaic structures

  • Piotr Caban,
  • Rafał Pietruszka,
  • Jarosław Kaszewski,
  • Monika Ożga,
  • Bartłomiej S. Witkowski,
  • Krzysztof Kopalko,
  • Piotr Kuźmiuk,
  • Katarzyna Gwóźdź,
  • Ewa Płaczek-Popko,
  • Krystyna Lawniczak-Jablonska and
  • Marek Godlewski

Beilstein J. Nanotechnol. 2021, 12, 578–592, doi:10.3762/bjnano.12.48

Graphical Abstract
  • luminescence characteristic for zinc substituted by aluminum and accompanied by vacancies. The AZO layers are found to be point defected depending on the surface preparation of the substrate. Also, the INBE/IDLE ratio depends on the GaAs surface etching procedure before the ALD process. Detailed sequence of
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Published 28 Jun 2021

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

  • Jakub Kierdaszuk,
  • Piotr Kaźmierczak,
  • Justyna Grzonka,
  • Aleksandra Krajewska,
  • Aleksandra Przewłoka,
  • Wawrzyniec Kaszub,
  • Zbigniew R. Zytkiewicz,
  • Marta Sobanska,
  • Maria Kamińska,
  • Andrzej Wysmołek and
  • Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

Graphical Abstract
  • contact with graphene. The lowest concentration of defects is observed for graphene deposited on nanowires with the lowest density. The contact between graphene and densely arranged nanowires leads to a large density of vacancies. On the other hand, grain boundaries are the main type of defects in
  • distribution in the layer. Coulomb interaction between GaN NWs and graphene could also create vacancies in graphene and, consequently, increase the density of defects. In turn, as reported recently, strain and carrier concentration can be influenced and modified by graphene defects as well [27][28][29][30
  • impact of the defects on graphene strain and carrier concentration. Experimental studies have shown that some kinds of defects distort the graphene lattice and, consequently, increase graphene strain [46][47]. For example, the vacancies elongate graphene lattice and induce tensile strain, while Stone
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Published 22 Jun 2021

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

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  • fewer oxygen vacancies and exhibits, therefore, a predominance of surface Ce+4, compared to a solvothermally synthesized nanoceria material with more oxygen vacancies, which produce a preponderance of surface Ce+3, it was hypothesized the NM-212 would have less catalytic activity. Another nanoscale
  • +. Increased Ce3+ is accompanied by an increase in oxygen vacancies that weaken the crystal lattice [14]. According to the dissolution framework by Gray and co-workers, Ce3+ can follow more dissolution pathways (including oxidative dissolution) than Ce4+ [59]. The much greater percentage of Ce3+ on the surface
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Published 04 Jun 2021

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

Graphical Abstract
  • increased by introducing oxygen vacancies into the crystal structure or by doping (e.g., n-type doping with niobium, Nb5+). Generally, two different terminations of STO(100) are known, that is, the surface can be either TiO2- or SrO-terminated. The TiO2 termination can be achieved by (ex situ) acid
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Published 21 May 2021

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

Graphical Abstract
  • graphene oxide, rGO) chemically or thermally. Through the partial removal of oxygen groups, the conductivity can be restored. Additionally, defects and vacancies are created [26]. Because of the ultra-high surface area per atom and the high electron transport along the graphene plane, rGO has a rapid and
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Published 15 Apr 2021

Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

  • Christian Preischl,
  • Linh Hoang Le,
  • Elif Bilgilisoy,
  • Armin Gölzhäuser and
  • Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

Graphical Abstract
  • ) [13], thin layers of porphyrin molecules [14][15], and surface-anchored metal-organic frameworks (SURMOFs) [16][17]. For oxide surfaces it is known that the activation mechanism is based on reactive oxygen vacancies, which are locally created by electron-stimulated oxygen desorption [18][19]. Whereas
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Published 07 Apr 2021

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

  • Rafal Zuzak,
  • Marek Szymonski and
  • Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

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  • defects could be identified within the surface [61][62][63][64][65]. These are mainly single or double hydrogen vacancies. This means that within a Ge dimer either one hydrogen atom is missing, this is called a single dangling bond (DB), or the dimer lacks both hydrogen atoms and the so-called dangling
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Published 05 Mar 2021

Fusion of purple membranes triggered by immobilization on carbon nanomembranes

  • René Riedel,
  • Natalie Frese,
  • Fang Yang,
  • Martin Wortmann,
  • Raphael Dalpke,
  • Daniel Rhinow,
  • Norbert Hampp and
  • Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 93–101, doi:10.3762/bjnano.12.8

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  • only a few vacancies could be obtained. Assembly of a stable hybrid membrane The experiments were repeated with a genetically modified species of c-His PM. This species has histidine-tags on every BR molecule and hence is strongly positively charged on the extracellular side. Thus, a chemical complex
  • maintain high substrate coverage despite low OD, the incubation was repeated four times. Despite the reduction of optical density, large areas of merged c-His PM monolayer could be observed as shown in Figure 3. The fused PM sheets showed small vacancies and fissures, however, the constant height of 5.0
  • solution. The absorption peak at 570 nm indicates that BR is functional. (a–c) Large-area agglomerates of c-His PM forming an immobilized quasi-monolayer with only a few vacancies on a functionalized NBPT CNM. (d) The electrostatic potential of the area shown in (c) reveals a uniform orientation of c-His
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Published 22 Jan 2021

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

Graphical Abstract
  • point defects. PL yields defect-related emission from all possible defects whereas EPR reveals only signals from paramagnetic defects [7]. Therefore, using EPR one obtains signals from the vacancies or interstitials that are ionized and become paramagnetic. In ZnO, singly ionized oxygen vacancies are
  • changes in the Raman spectrum. In particular, this method is used for carbon materials to detect the so-called D-band, which belongs to sp3-hybridized carbon. For the occurrence of the D-band either C dangling bonds on the surface, C interstitials, or C vacancies need to exist. Raman spectra of metal
  • ionized oxygen vacancies located either in volume or at the surface of the material. (b) PL spectra showing all possible defect centers, including non-paramagnetic ones. The defects emit visible light yielding a broad emission band [4]. (c) Tauc plot obtained from UV–vis reflectance measurements
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Published 13 Jan 2021

Unravelling the interfacial interaction in mesoporous SiO2@nickel phyllosilicate/TiO2 core–shell nanostructures for photocatalytic activity

  • Bridget K. Mutuma,
  • Xiluva Mathebula,
  • Isaac Nongwe,
  • Bonakele P. Mtolo,
  • Boitumelo J. Matsoso,
  • Rudolph Erasmus,
  • Zikhona Tetana and
  • Neil J. Coville

Beilstein J. Nanotechnol. 2020, 11, 1834–1846, doi:10.3762/bjnano.11.165

Graphical Abstract
  • that facilitates easy adsorption of organic molecules and their transfer onto the active sites of TiO2 [22][23]. Additionally, the interaction between SiO2 and TiO2 could result in the creation of oxygen vacancies that promote charge-transfer processes and, hence, enhance the photocatalytic activity
  • electronegativity and ionic radius between the metal ions and titania can alter the concentration of oxygen vacancies in the TiO2 lattice. Hence, the higher electronegativity of Ni2+ in NiPS [43] can induce defect sites within the structure and, consequently, alter light absorption and charge-transfer processes [51
  • ][67]. These oxygen vacancies easily act as hole traps that lower the charge-carrier recombination rate, resulting in more free electrons that can give rise to more superoxide radicals upon reaction with adsorbed surface oxygen [23]. Furthermore, the flake-like NiPS morphology could act as a suitable
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Published 09 Dec 2020

Nanocasting synthesis of BiFeO3 nanoparticles with enhanced visible-light photocatalytic activity

  • Thomas Cadenbach,
  • Maria J. Benitez,
  • A. Lucia Morales,
  • Cesar Costa Vera,
  • Luis Lascano,
  • Francisco Quiroz,
  • Alexis Debut and
  • Karla Vizuete

Beilstein J. Nanotechnol. 2020, 11, 1822–1833, doi:10.3762/bjnano.11.164

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  • to point out that a comparison of bandgap values with different BiFeO3 samples is very difficult as particle shape, size, phase purity, as well as oxygen vacancies have a strong impact on the electronic structure of the resulting material. Photocatalytic activity The photocatalytic activity of all
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Published 07 Dec 2020

Oxidation of Au/Ag films by oxygen plasma: phase separation and generation of nanoporosity

  • Abdel-Aziz El Mel,
  • Said A. Mansour,
  • Mujaheed Pasha,
  • Atef Zekri,
  • Janarthanan Ponraj,
  • Akshath Shetty and
  • Yousef Haik

Beilstein J. Nanotechnol. 2020, 11, 1608–1614, doi:10.3762/bjnano.11.143

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  • silver and gold. In addition, it was shown that the preferential oxidation of silver resulted in a solid-state diffusion of silver toward the surface where it oxidized and formed nanoporous microspheres. The gold phase remaining in the film exhibited nanoporosity due to the injected vacancies at the
  • silver oxide, its concentration was low inside the film. This indicates that the majority of the silver atoms diffused out of the film leaving behind a gold-rich nanoporous scaffold. The nanoporosity in the gold film probably resulted from the generation of vacancies within the film during the oxidation
  • film can be explained by the Kirkendall effect [24]. More precisely, as silver diffuses out of the alloy film, vacancies are injected into the metal/oxide interface and migrate within the fast-diffusing medium (represented here by the metal alloy in Figure 8c). As the oxidation process evolves
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Published 22 Oct 2020

Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir

  • Mathias Franz,
  • Romy Junghans,
  • Paul Schmitt,
  • Adriana Szeghalmi and
  • Stefan E. Schulz

Beilstein J. Nanotechnol. 2020, 11, 1439–1449, doi:10.3762/bjnano.11.128

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  • electron vacancies play an important role within the anodic reactions at the silicon surface. The combined reaction can be written as: This reaction summarises two etching mechanisms related to n, the number of consumed holes h+ per etched Si atom. The first mechanism is correlated to n = 4. The silicon
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Published 23 Sep 2020

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

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  • 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
  • GaAs [62], and P vacancies in InP(110) [63]. Due to the common nature of these defects in other semiconductors and the similarity in imaging character, we thus attribute this defect to most likely be a Si vacancy. Further discussion of our assignment and additional evidence is given later as part of
  • localized negative charge (similar to the dark halo around a DB in Figure 2a-1 or the vacancies in Figure 4). At this point, one could be tempted to assign the dark feature to the same vacancy defect as in Figure 4 due to their similar likeness. However, this species is found to be unstable and irreversibly
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Published 07 Sep 2020

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS2 field-effect transistors

  • Jakub Jadwiszczak,
  • Pierce Maguire,
  • Conor P. Cullen,
  • Georg S. Duesberg and
  • Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

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  • improvement of both the carrier mobility in the transistor channel and the electrical conductance of the MoS2, due to doping with ion beam-created sulfur vacancies. Larger areal irradiations introduce a higher concentration of scattering centers, hampering the electrical performance of the device. In addition
  • , we find that irradiating the electrode–channel interface has a deleterious impact on charge transport when contrasted with irradiations confined only to the transistor channel. Keywords: 2D materials; contacts; defect engineering; helium ion microscope; ion beam doping; vacancies; two-dimensional
  • of well-performing monolayer TMD films [3][4][5], leading to viable large-scale integration of on-chip TMD FETs. With device miniaturization, it becomes key to understand the impact of defects such as chalcogen vacancies on the electrical transport properties of FETs based on 2D semiconductors. This
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Published 04 Sep 2020

Structural and electronic properties of SnO2 doped with non-metal elements

  • Jianyuan Yu,
  • Yingeng Wang,
  • Yan Huang,
  • Xiuwen Wang,
  • Jing Guo,
  • Jingkai Yang and
  • Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

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  • oxygen vacancies, and thus, increase the charge density of the Sn sites. The replacement of O with N can simultaneously decrease the release of CO2. While there are reports on experiments regarding the doping of SnO2 with non-metal elements, the mechanism of the effect of non-metal element doping on the
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Published 03 Sep 2020

Adsorption behavior of tin phthalocyanine onto the (110) face of rutile TiO2

  • Lukasz Bodek,
  • Mads Engelund,
  • Aleksandra Cebrat and
  • Bartosz Such

Beilstein J. Nanotechnol. 2020, 11, 821–828, doi:10.3762/bjnano.11.67

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  • molecule towards the surface. Also, the electrostatic landscape of a reduced rutile (110) surface prepared in UHV by sputter–anneal cycles is complicated. The cleaning procedure creates oxygen vacancies, which in turn leads to the formation of polarons near the surface [29][30][31]. Additionally, water
  • molecules may dissociate at oxygen vacancies and form hydroxy groups on the surface. Both species can be recognized in our STM images and they both lead to the formation of dipole moments pointing away from the surface [32]. Their local arrangement may play a significant role in the interaction between a
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Published 26 May 2020

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

  • Stefania Castelletto,
  • Faraz A. Inam,
  • Shin-ichiro Sato and
  • Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

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  • /compatibility of the active quantum source and the device in use, and they have limitations in terms of scalability. The type of point defects that should be addressed is also a key element and is generally substitutional dopants, native vacancies, and dopant-vacancy complexes. The space of possible defects is
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Published 08 May 2020

Effect of Ag loading position on the photocatalytic performance of TiO2 nanocolumn arrays

  • Jinghan Xu,
  • Yanqi Liu and
  • Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

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  • the catalyst, so the catalyst needs to have a certain adsorption capacity for dye molecules. Due to the presence of oxygen vacancies, the surface of TiO2 is usually negatively charged and has a good adsorption capacity for cationic dye molecules [36]. Commonly used cationic dyes are rhodamine, methyl
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Published 05 May 2020
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