Graphene on SiC(0001) inspected by dynamic atomic force microscopy at room temperature

• Mykola Telychko,
• Jan Berger,
• Zsolt Majzik,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2015, 6, 901–906, doi:10.3762/bjnano.6.93

• specifically chosen for the conditions when the graphene contrast provided by the Δf is not giving atomic resolution in the attractive regime. Kelvin probe force measurements (KPFM) were also done in the constant-height mode, with a slow feedback between the measurement points, to compensate the tilt of the

• within the q-6 structure of graphene a Kelvin-probe measurement [24] has been performed on the bright and dark areas (highs and lows of the q-6 modulation) in the Δf image, at 0.5 nm from the setpoint, further from the sample. In Figure 2b, the two corresponding parabolas show no difference neither in

Kelvin probe force microscopy in liquid using electrochemical force microscopy

• Liam Collins,
• Stephen Jesse,
• Jason I. Kilpatrick,
• Alexander Tselev,
• M. Baris Okatan,
• Sergei V. Kalinin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2015, 6, 201–214, doi:10.3762/bjnano.6.19

• , Ireland Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA 10.3762/bjnano.6.19 Abstract Conventional closed loop-Kelvin probe force microscopy

• properties at the solid–liquid interface. Keywords: diffuse charge dynamics; double layer charging; electrochemical force microscopy; electrochemistry; Kelvin probe force microscopy; Introduction Many important physical, chemical and biological processes including wetting, adsorption, electronic transfer

• [18], electrochemical [19] and ionic [15] functionality on the nanoscale have been developed. A paradigmatic example of such development is closed loop-Kelvin probe force microscopy (KPFM) [20], which has become a widely used voltage-modulated SPM technique for the measurement of surface potential

Advanced atomic force microscopy techniques II

• Thilo Glatzel,
• Ricardo Garcia and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2014, 5, 2326–2327, doi:10.3762/bjnano.5.241

• batteries for a comparison of their nanoscale electrical, electrochemical, and morphological properties [6] or the analysis of CdS quantum dots on TiO2 by a combination of AFM and X-ray photoelectron spectroscopy [7]. The folding and rupture of graphene on SiC analyzed by non-contact AFM and Kelvin probe

Advances in NO₂ sensing with individual single-walled carbon nanotube transistors

• Kiran Chikkadi,
• Matthias Muoth,
• Cosmin Roman,
• Miroslav Haluska and
• Christofer Hierold

Beilstein J. Nanotechnol. 2014, 5, 2179–2191, doi:10.3762/bjnano.5.227

• , the different sensing mechanisms which may be present in a CNFET sensor are discussed in detail. Adsorption on the metal The work function of a metal is known to be sensitive to the adsorption of gaseous surface species. Methods such as Kelvin probe [31], scanning tunneling spectroscopy, X-ray and

Electronic and electrochemical doping of graphene by surface adsorbates

• Hugo Pinto and
• Alexander Markevich

Beilstein J. Nanotechnol. 2014, 5, 1842–1848, doi:10.3762/bjnano.5.195

• in this case is the reaction in Equation 1. The water molecules required for the reaction are assumed to be located at the graphene/SiO2 interface. Indeed, the presence of water layers on the surface of SiO2 films grown on Si has been confirmed by Kelvin probe microscopy, X-ray spectroscopy and FTIR

Highly NO₂ sensitive caesium doped graphene oxide conductometric sensors

• Carlo Piloto,
• Marco Notarianni,
• Mahnaz Shafiei,
• Elena Taran,
• Dilini Galpaya,
• Cheng Yan and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 1073–1081, doi:10.3762/bjnano.5.120

• microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), Raman spectroscopy and Kelvin probe force microscopy (KPFM). XPS data were acquired using a Kratos Axis ULTRA X-ray photoelectron spectrometer incorporating a 165 mm hemispherical electron energy analyser. The incident

Uncertainties in forces extracted from non-contact atomic force microscopy measurements by fitting of long-range background forces

• Adam Sweetman and
• Andrew Stannard

Beilstein J. Nanotechnol. 2014, 5, 386–393, doi:10.3762/bjnano.5.45

• exception to this is the discussion that has surrounded Kelvin probe force microscopy (KPFM) where accurate modelling of this long-range regime is critical to interpreting results [8][9][10]. Nonetheless, long-range forces are readily subtracted in the literature using this method, often using simplistic

Effect of contaminations and surface preparation on the work function of single layer MoS₂

• Oliver Ochedowski,
• Kolyo Marinov,
• Nils Scheuschner,
• Artur Poloczek,
• Benedict Kleine Bussmann,
• Janina Maultzsch and
• Marika Schleberger

Beilstein J. Nanotechnol. 2014, 5, 291–297, doi:10.3762/bjnano.5.32

• , e.g., lower the contact resistance and improve their performance. First experiments adressing this issue for MoS2 by using Kelvin probe force microscopy (KPFM) have already been reported [28][29]. However, these measurements were not done on SLM but bilayer MoS2 (BLM) and higher layer numbers and the

• measurements were performed under ambient conditions using amplitude modulated KPFM, both having a great impact on the results. In this work we study the work function of SLM on a standard SiO2/Si substrate using non-contact atomic force microscopy (NC-AFM) and Kelvin probe force microscopy in situ. In our

• excellent agreement again underlines the importance of UHV measurements if intrinsic properties are to be probed. Conclusion In conclusion we have performed the first in situ Kelvin probe force microscopy measurements on single layers of MoS2 on a SiO2 substrate. We find work functions of ΦSLM = 4.49 eV

Noncontact atomic force microscopy II

• Mehmet Z. Baykara and
• Udo D. Schwarz

Beilstein J. Nanotechnol. 2014, 5, 289–290, doi:10.3762/bjnano.5.31

• how new experimental methods that are based on the working principle of NC-AFM are continuously being developed, which is documented by a number of papers dealing with multi-frequency AFM as well as Kelvin probe force microscopy (KPFM). We thank all the scientists who have submitted their outstanding

Routes to rupture and folding of graphene on rough 6H-SiC(0001) and their identification

• M. Temmen,
• O. Ochedowski,
• B. Kleine Bussmann,
• M. Schleberger,
• M. Reichling and
• T. R. J. Bollmann

Beilstein J. Nanotechnol. 2013, 4, 625–631, doi:10.3762/bjnano.4.69

• Kelvin probe force microscopy (KPFM). SHI irradiation results in rupture of the SLG sheets, thereby creating foldings and bilayer graphene (BLG). Applying the other modification methods creates enlarged (twisted) graphene foldings that show rupture along preferential edges of zigzag and armchair type

• ) measured by KPFM. Keywords: graphene; Kelvin probe force microscopy (KPFM), local contact potential difference (LCPD); non-contact atomic force microscopy (NC-AFM); SiC; Introduction Since its discovery in 2004 [1], graphene, the 2D crystal with a honeycomb lattice of sp2-bonded carbon atoms, has been

• different BLG stackings, we investigate the topography by non-contact atomic force microscopy (NC-AFM) combined with measuring the local contact potential differences (LCPD) using Kelvin probe force microscopy (KPFM). Experimental Graphene is exfoliated from a HOPG crystal (Momentive Performance Materials

Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• . Although the nanocrystalline TiO2 photoelectrode of a DSC consists of sintered nanoparticles, there are few studies on the nanoscale properties. We focus on the microscopic work function and surface photovoltage (SPV) determination of TiO2 photoelectrodes using Kelvin probe force microscopy in combination

• built-in potential on the DSC performance at the TiO2/SnO2:F interface, investigated on a nanometer scale by KPFM measurements under visible light illumination, has not been resolved so far. Keywords: atomic force microscopy (AFM); dye-sensitized solar cells (DSC); Kelvin probe force microscopy (KPFM

• ) TiO2 have been investigated with such a macroscopic Kelvin probe (KP) revealing details about the electronic structure [21][22][23], trap states [24], the surface dipole [25], charge-carrier dynamics [26], and indicating changes upon chemical treatments [24][27][28][29]. KP studies have helped to

Characterization of the mechanical properties of qPlus sensors

• Jan Berger,
• Martin Švec,
• Martin Müller,
• Martin Ledinský,
• Antonín Fejfar,
• Pavel Jelínek and
• Zsolt Majzik

Beilstein J. Nanotechnol. 2013, 4, 1–9, doi:10.3762/bjnano.4.1

• the differential stage. This procedure can be applied to minimize coupling from other sources, e.g., bias modulation used for Kelvin probe measurements. A piezo tube is used for mechanical excitation. Apart from the rubber legs of this small instrument there is no additional vibration isolation

The memory effect of nanoscale memristors investigated by conducting scanning probe microscopy methods

• César Moreno,
• Carmen Munuera,
• Xavier Obradors and
• Carmen Ocal

Beilstein J. Nanotechnol. 2012, 3, 722–730, doi:10.3762/bjnano.3.82

• by means of Kelvin probe force microscopy [3], the results presented here support the memristor memory effect capable of memorizing the amount of charge that has passed through it. In order to gain insight to this issue, analysis of the I–V characteristics is needed. As commented above, vertical

Low-temperature synthesis of carbon nanotubes on indium tin oxide electrodes for organic solar cells

• Andrea Capasso,
• Luigi Salamandra,
• Aldo Di Carlo,
• John M. Bell and
• Nunzio Motta

Beilstein J. Nanotechnol. 2012, 3, 524–532, doi:10.3762/bjnano.3.60

• -modified ITO surfaces was measured by the Kelvin probe method to be 4.95 eV, resulting in an improved matching to the highest occupied molecular orbital level of the P3HT. This is in turn expected to increase the hole transport and collection at the anode, contributing to the significant increase of

• current density and open-circuit voltage observed in test cells created with such MWCNT-enhanced electrodes. Keywords: carbon nanotubes; electrode; indium tin oxide; Kelvin probe; organic photovoltaics; Introduction Following the original proposal for the creation of plastic solar cells [1], many

• measured the WF of the as-created electrode. Kelvin probe and ultraviolet photoelectron spectroscopy (UPS) are the techniques usually employed for this purpose; however, there are substantial differences in how the WF is measured. The Kelvin probe method measures, in air, the difference in WF between a

Graphite, graphene on SiC, and graphene nanoribbons: Calculated images with a numerical FM-AFM

• Fabien Castanié,
• Laurent Nony,
• Sébastien Gauthier and
• Xavier Bouju

Beilstein J. Nanotechnol. 2012, 3, 301–311, doi:10.3762/bjnano.3.34

• sample upon interaction into account. One of the main difficulties here is to handle the different time scales that characterize the different dynamic behaviors of the oscillator and the AFM junction atoms. Finally, a Kelvin probe force microscopy module (KPFM) [86][87][88] will be included in a near

Junction formation of Cu₃BiS₃ investigated by Kelvin probe force microscopy and surface photovoltage measurements

• Fredy Mesa,
• William Chamorro,
• William Vallejo,
• Robert Baier,
• Thomas Dittrich,
• Alexander Grimm,
• Martha C. Lux-Steiner and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2012, 3, 277–284, doi:10.3762/bjnano.3.31

• to be developed. We present an investigation of the Cu3BiS3 absorber layer and the junction formation with CdS, ZnS and In2S3 buffer layers. Kelvin probe force microscopy shows the granular structure of the buffer layers with small grains of 20–100 nm, and a considerably smaller work-function

• charge-selective contact has to be increased. Keywords: buffer layer; Cu3BiS3; Kelvin probe force microscopy; solar cells; Introduction Thin-film solar cells based on absorbers made from Cu(In,Ga)Se2 [1] or CdTe [2] reach the highest efficiencies currently available. Both semiconductors are interesting

• from the chemical bath will be deposited. Surface characterization by Kelvin probe force microscopy (KPFM) In order to comparatively characterize the growth and electronic properties of the different buffers, we performed KPFM measurements on the Cu3BiS3 samples with all three buffer layers, and as a

An NC-AFM and KPFM study of the adsorption of a triphenylene derivative on KBr(001)

• Antoine Hinaut,
• Adeline Pujol,
• Florian Chaumeton,
• David Martrou,
• André Gourdon and
• Sébastien Gauthier

Beilstein J. Nanotechnol. 2012, 3, 221–229, doi:10.3762/bjnano.3.25

• designed molecule, consisting of a flat aromatic triphenylene core equipped with six flexible propyl chains ending with polar cyano groups, is investigated by using atomic force microscopy in the noncontact mode (NC-AFM) coupled to Kelvin probe force microscopy (KPFM) in ultrahigh vacuum at room

• room for progress as shown by the impressive submolecular resolution that has been demonstrated in recent works on the adsorption of pentacene [14] or decastarphene [15] molecules on Cu(111) and on a NaCl(001) bilayer on Cu(111). During the same period, Kelvin probe force microscopy (KPFM) has been

Quantitative multichannel NC-AFM data analysis of graphene growth on SiC(0001)

• Christian Held,
• Thomas Seyller and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2012, 3, 179–185, doi:10.3762/bjnano.3.19

• representation of multichannel NC-AFM data sets in a quantitative fashion. Presentation and analysis are exemplified for topography and contact-potential data for graphene grown epitaxially on 6H-SiC(0001), as recorded by Kelvin probe force microscopy in ultrahigh vacuum. Sample preparations by thermal

• identification of the graphene layer thickness from the local contact potential as determined by means of Kelvin probe force microscopy (KPFM) [11][12]. As a further advantage, KPFM determines step heights more accurately than STM or AFM with constant bias [13] and is therefore employed in this study to

• almost the same carbon density as one layer of graphene [16]. Experimental Noncontact atomic force microscopy (NC-AFM) measurements were performed in ultrahigh vacuum (UHV, p < 2·10−10 mbar) by means of a home-built microscope similar to the one described in [17]. Kelvin probe force microscopy (KPFM

Distinguishing magnetic and electrostatic interactions by a Kelvin probe force microscopy–magnetic force microscopy combination

• Miriam Jaafar,
• Oscar Iglesias-Freire,
• Luis Serrano-Ramón,
• Manuel Ricardo Ibarra,
• Jose Maria de Teresa and
• Agustina Asenjo

Beilstein J. Nanotechnol. 2011, 2, 552–560, doi:10.3762/bjnano.2.59

• ., they exhibit large surface potential differences causing heterogeneous electrostatic interaction between the tip and the sample that could be interpreted as a magnetic interaction. To distinguish clearly the origin of the tip–sample forces we propose to use a combination of Kelvin probe force

• ; Kelvin probe force microscopy; magnetic force microscopy; magnetic nanostructures; Introduction The most valuable asset of scanning force microscopy (SFM) is its versatility for studying a variety of interactions between the tip and the sample surface [1][2][3]. The SFM techniques can be used to detect

• magnetic field during the MFM operation [14][15][16]; (ii) performing a combination of Kelvin probe force microscopy (KPFM) [17][18] and MFM to compensate the electrostatic contribution to the frequency shift signal. In the first method the evolution of the MFM signal with the magnetic field is a signature

The role of the cantilever in Kelvin probe force microscopy measurements

• George Elias,
• Thilo Glatzel,
• Ernst Meyer,
• Alex Schwarzman,
• Amir Boag and
• Yossi Rosenwaks

Beilstein J. Nanotechnol. 2011, 2, 252–260, doi:10.3762/bjnano.2.29

• cantilever in quantitative Kelvin probe force microscopy (KPFM) is rigorously analyzed. We use the boundary element method to calculate the point spread function of the measuring probe: Tip and cantilever. The calculations show that the cantilever has a very strong effect on the absolute value of the

• calculated and found to be relatively small. Keywords: boundary elements method; cantilever; convolution; Kelvin probe force microscopy; point spread function; Introduction The effect of the measuring probe in electrostatic force based microscopies, such as Kelvin probe force microscopy (KPFM) [1], is very

Single-pass Kelvin force microscopy and dC/dZ measurements in the intermittent contact: applications to polymer materials

• Sergei Magonov and
• John Alexander

Beilstein J. Nanotechnol. 2011, 2, 15–27, doi:10.3762/bjnano.2.2

• . Therefore, macroscopic Kelvin probe studies of Langmuir–Blodgett layers of different FnHm revealed a strong surface potential of −0.8 V [6][7] that is assigned to vertically oriented molecular chains with fluorinated parts facing air. Therefore, the fluoroalkane structures are the useful models for the

• of charges and interfacial and field-induced dipoles. In polar polymers, the situation can be much more complicated and the apparent surface potential of polymer molecules has to be discussed in connection with macroscopic Kelvin probe studies of thin PMMA films. These studies revealed that surface

Defects in oxide surfaces studied by atomic force and scanning tunneling microscopy

• Thomas König,
• Georg H. Simon,
• Lars Heinke,
• Leonid Lichtenstein and
• Markus Heyde

Beilstein J. Nanotechnol. 2011, 2, 1–14, doi:10.3762/bjnano.2.1

• surface termination by NC-AFM with atomic resolution, point defects in magnesium oxide on Ag(001) and line defects in aluminum oxide on NiAl(110), respectively, were thoroughly studied. The contact potential was determined by Kelvin probe force microscopy (KPFM) and the electronic structure by scanning

• applied on thin oxide films beyond imaging the topography of the surface atoms. Keywords: aluminum oxide; charge state; contact potential; defects; domain boundaries; dynamic force microscopy; frequency modulation atomic force microscopy; Kelvin probe force microscopy; magnesium oxide; non-contact atomic

• defects in oxide surfaces was studied by non-contact atomic force microscopy (NC-AFM) and scanning tunneling microscopy (STM). Furthermore, the contact potential was determined by Kelvin probe force microscopy (KPFM). This technique has a high spatial resolution, thus avoiding averaging over various

Scanning probe microscopy and related methods

• Ernst Meyer

Beilstein J. Nanotechnol. 2010, 1, 155–157, doi:10.3762/bjnano.1.18

• molecules on surfaces. AFM has evolved considerably in the last few years, where new operation modes, such as non-contact force microscopy (nc-AFM), Kelvin probe force microscopy (KPFM) or friction force microscopy (FFM), were developed. One main focus is the high resolution capabilities of nc-AFM, which

• Microscopy, FMM: Force Modulation Microscopy, ic-AFM: intermittent contact AFM, TMAFM: tapping mode AFM, nc-AFM: non-contact AFM, KPFM: Kelvin probe force microscopy, EFM: Electrostatic force microscopy, MFM: Magnetic force microscopy, MRFM: Magnetic resonance force microscopy, NSOM: Near-field scanning