Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• ) surface with O2 exposure using Kelvin probe force microscopy. A drop in contact potential difference was observed at the steps, indicating that the work function locally decreased. Moreover, for the first time, we found that the drop in contact potential difference at a <1−11> step was larger than that at

• steps in the catalytic reaction. Keywords: catalyst; Kelvin probe force microscopy; Smoluchowski effect; step; titanium dioxide; Introduction Titanium dioxide (TiO2) has attracted considerable interest for its promising applications as a photocatalyst and as catalyst support, as well as in gas sensors

• observed with a lateral resolution of several nanometers by Kelvin probe force microscopy (KPFM) [29][30]. However, the dependence of surface potential on direction and structure of steps such as [001], and has not yet been clarified. In scanning tunneling microscopy (STM) [31] studies, three typical

Comparing a porphyrin- and a coumarin-based dye adsorbed on NiO(001)

• Sara Freund,
• Antoine Hinaut,
• Nathalie Marinakis,
• Edwin C. Constable,
• Ernst Meyer,
• Catherine E. Housecroft and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2019, 10, 874–881, doi:10.3762/bjnano.10.88

• Kelvin probe force microscopy measurements. Keywords: coumarin; Kelvin probe force microscopy; metal oxide; molecular resolution; nickel oxide (NiO); non-contact atomic force microscopy; porphyrin; Introduction With regard to its use in dye-sensitized solar cells (DSSCs), the wide-bandgap n-type

• investigated by Kelvin probe force microscopy (KPFM) [25]. This technique is used to observe and quantify the contact potential difference (CPD) changes between the metal oxide surface and the molecular layers and to determine the corresponding dipole moments. Results and Discussion Atomically clean NiO

• ≈ 165 kHz, quality factor Qf1 ≈ 30000) with compensated contact potential difference. Kelvin probe force microscopy was performed in frequency-modulation mode using a voltage modulation applied together with the dc compensation voltage to the sample (Vac = 800 mV and fac = 1 kHz or 250 Hz). (a

Novel reversibly switchable wettability of superhydrophobic–superhydrophilic surfaces induced by charge injection and heating

• Xiangdong Ye,
• Junwen Hou and
• Dongbao Cai

Beilstein J. Nanotechnol. 2019, 10, 840–847, doi:10.3762/bjnano.10.84

• (compared to Figure 2b). Therefore, we conclude that the change in coating wettability was not induced by the surface morphology. To establish the reason for the wettability change, Kelvin probe force microscopy was used to detect the surface potential of the electrode contact area and the electrode non

• principle of Kelvin probe force microscopy, in the uncharged area, the surface potentials fluctuate significantly and result in random data, whereas in the charged area, the surface potentials remain steady. As we have known, the electrowetting phenomenon caused by electric-field-driven solid–liquid

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• -domain EFM to measure ionic transport [7][12], time-resolved electrochemical strain microscopy (ESM) to measure ionic transport [8][13], various time-resolved Kelvin probe force microscopy (KPFM) techniques that utilize either optical pump-probe or advanced signal processing to measure time-resolved

• . One example of this is in time-resolved Kelvin probe force microscopy (KPFM) experiments that measure the surface photovoltage of a sample as a function of time after a light source is pulsed. This was first implemented by Takihara et al. to measure the photovoltage dynamics of a sample at time scales

Nitrous oxide as an effective AFM tip functionalization: a comparative study

• Taras Chutora,
• Bruno de la Torre,
• Pingo Mutombo,
• Jack Hellerstedt,
• Jaromír Kopeček,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2019, 10, 315–321, doi:10.3762/bjnano.10.30

• spectroscopy measurements, i.e., the interaction energy toward different atomic species in force spectroscopy, the contact potential difference in Kelvin probe force microscopy (KPFM) [9][29] and vibrational levels of inelastic tunneling spectroscopy (IETS) [30][31]. A particular termination of the tip may be

Scanning probe microscopy for energy-related materials

• Rüdiger Berger,
• Benjamin Grévin,
• Philippe Leclère and
• Yi Zhang

Beilstein J. Nanotechnol. 2019, 10, 132–134, doi:10.3762/bjnano.10.12

• microscopy (cAFM) and Kelvin probe force microscopy (KPFM) are the major methods that enable the study of the movement of charge carriers and their pathways [1]. We note that the KPFM method is rapidly becoming a tool capable of time-resolved studies. In this context, Yann Almadori and co-workers discuss the

A scanning probe microscopy study of nanostructured TiO₂/poly(3-hexylthiophene) hybrid heterojunctions for photovoltaic applications

• Laurie Letertre,
• Roland Roche,
• Olivier Douhéret,
• Hailu G. Kassa,
• Denis Mariolle,
• Nicolas Chevalier,
• Łukasz Borowik,
• Philippe Dumas,
• Benjamin Grévin,
• Roberto Lazzaroni and
• Philippe Leclère

Beilstein J. Nanotechnol. 2018, 9, 2087–2096, doi:10.3762/bjnano.9.197

• photovoltaic process and the correlation to the nanoscale morphology. A down-shift of the vacuum level of the TiO2 surface upon grafting was measured by Kelvin probe force microscopy (KPFM), evidencing the formation of a dipole at the TiO2/P3HT-COOH interface. Upon in situ illumination, a positive photovoltage

• theoretical and material design perspective. Keywords: hybrid heterojunctions; hybrid photovoltaic; Kelvin probe force microscopy; photoconductive-AFM; photo-KPFM; poly(3-hexylthiophene); TiO2; Introduction Over the past decades, a large range of photovoltaic (PV) technologies have been developed for the

• photoconductive-AFM (PC-AFM) and photo-assisted Kelvin probe force microscopy (photo-KPFM) to follow the photovoltaic response, i.e., photocurrent and photovoltage, respectively, at the nanoscale under illumination, in order to understand the local physical processes taking place during the photoconversion of

Numerical analysis of single-point spectroscopy curves used in photo-carrier dynamics measurements by Kelvin probe force microscopy under frequency-modulated excitation

• Pablo A. Fernández Garrillo,
• Benjamin Grévin and
• Łukasz Borowik

Beilstein J. Nanotechnol. 2018, 9, 1834–1843, doi:10.3762/bjnano.9.175

• nanostructure and photo-transport mechanisms has become of crucial importance for the development of many emerging photovoltaic technologies. In this context, Kelvin probe force microscopy under frequency-modulated excitation has emerged as a useful technique for probing photo-carrier dynamics and gaining

• experimental results as additional information about the photo-carrier dynamics of the sample can be gained via the numerical analysis. Keywords: carrier dynamics; carrier lifetime; carrier recombination; Kelvin probe force microscopy; nanostructured photovoltaics; numerical simulations; photo-carrier

• this context, few teams around the world have recently began to develop time-resolved scanning probe microscopies (SPM) techniques, aimed at addressing the photo-carrier dynamics at the local scale in photoactive materials and devices. At this point, Kelvin probe force microscopy (KPFM) emerged as a

Know your full potential: Quantitative Kelvin probe force microscopy on nanoscale electrical devices

• Amelie Axt,
• Ilka M. Hermes,
• Victor W. Bergmann,
• Niklas Tausendpfund and
• Stefan A. L. Weber

Beilstein J. Nanotechnol. 2018, 9, 1809–1819, doi:10.3762/bjnano.9.172

• investigate the influence of the operation method in Kelvin probe force microscopy (KPFM) on the measured potential distribution. KPFM is widely used to map the nanoscale potential distribution in operating devices, e.g., in thin film transistors or on cross sections of functional solar cells. Quantitative

• mode; AM off resonance; AM second eigenmode; cross section; crosstalk; field effect transistor; FM-KPFM; frequency modulation heterodyne; frequency modulation sideband; quantitative Kelvin probe force microscopy; solar cells; Introduction In this study, we compare the most commonly used amplitude

• modulation (AM) and frequency modulation (FM) Kelvin probe force microscopy (KPFM) methods under ambient conditions to investigate how these methods can measure quantitative variations in the local contact potential difference (CPD). KPFM is a scanning force microsopcy (SFM) method that correlates the local

Multimodal noncontact atomic force microscopy and Kelvin probe force microscopy investigations of organolead tribromide perovskite single crystals

• Yann Almadori,
• David Moerman,
• Jaume Llacer Martinez,
• Philippe Leclère and
• Benjamin Grévin

Beilstein J. Nanotechnol. 2018, 9, 1695–1704, doi:10.3762/bjnano.9.161

• du Parc 20, B7000 Mons, Belgium 10.3762/bjnano.9.161 Abstract In this work, methylammonium lead tribromide (MAPbBr3) single crystals are studied by noncontact atomic force microscopy (nc-AFM) and Kelvin probe force microscopy (KPFM). We demonstrate that the surface photovoltage and crystal

• . Keywords: carrier lifetime; ion migration; Kelvin probe force microscopy (KPFM); noncontact atomic force microscopy (nc-AFM); organic–inorganic hybrid perovskites; photostriction; single crystals; surface photovoltage (SPV); time-resolved surface photovoltage; Introduction Organic–inorganic hybrid

• conversion efficiencies exceeding 20% and several kinds of optoelectronic devices, including efficient light-emitting diodes [3], laser devices [4] and high-gain photodetectors [5]. Recently, Kelvin probe force microscopy (KPFM) has been used to investigate the impact of grain boundaries (GBs) on the

Artifacts in time-resolved Kelvin probe force microscopy

• Sascha Sadewasser,
• Nicoleta Nicoara and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2018, 9, 1272–1281, doi:10.3762/bjnano.9.119

• 10.3762/bjnano.9.119 Abstract Kelvin probe force microscopy (KPFM) has been used for the characterization of metals, insulators, and semiconducting materials on the nanometer scale. Especially in semiconductors, the charge dynamics are of high interest. Recently, several techniques for time-resolved

• deflection detection system. Finally, guidelines for avoiding such artifacts are given. Keywords: Kelvin probe force microscopy; time-resolved; Introduction Kelvin probe force microscopy (KPFM) [1] has been widely used for the characterization of metals, insulators, and semiconducting materials on the

• quality factor. The first three (i = 1,2,3) eigenmodes of the cantilever are used. Only the electrostatic forces relevant for electrostatic and Kelvin probe force microscopy are considered according to [2]: Here, Vdc is the applied dc voltage, Vac the ac-detection voltage, fac the frequency of the ac

Anchoring of a dye precursor on NiO(001) studied by non-contact atomic force microscopy

• Sara Freund,
• Antoine Hinaut,
• Nathalie Marinakis,
• Edwin C. Constable,
• Ernst Meyer,
• Catherine E. Housecroft and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2018, 9, 242–249, doi:10.3762/bjnano.9.26

• recorded by Kelvin probe force microscopy (KPFM) [68]. The CPD arises from the work function difference between the tip and the substrate and is altered by surface charges or dipoles. The voltage needed to compensate for the electrostatic forces due to this potential difference is measured in KPFM. The CPD

• ), using silicon cantilever (Nanosensors PPP-NCR, stiffness k = 20–30 N/m, resonance frequency f1 around 165 kHz, Qf1 factor around 30000, torsional frequency fTR around 1.5 MHz, and QTR factors around 100000) with compensated contact potential difference (CPD). Kelvin probe force microscopy was performed

Combined scanning probe electronic and thermal characterization of an indium arsenide nanowire

• Tino Wagner,
• Fabian Menges,
• Heike Riel,
• Bernd Gotsmann and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2018, 9, 129–136, doi:10.3762/bjnano.9.15

• spots may put limits on device integration. Therefore, being able to observe profiles of both electronic and thermal device properties at the nanoscale is important. Here, we show measurements by scanning thermal and Kelvin probe force microscopy of the same 60 nm diameter indium arsenide nanowire in

• operation. The observed temperature along the wire is substantially elevated near the contacts and deviates from the bell-shaped temperature profile one would expect from homogeneous heating. Voltage profiles acquired by Kelvin probe force microscopy not only allow us to determine the electrical nanowire

• . Keywords: contact resistance; Kelvin probe force microscopy (KFM); nanowire; scanning thermal microscopy (SThM); self-heating; Introduction Electronic and thermal properties of nanoscale devices are innately coupled. The charge carriers in most conductors release energy by scattering at defects or phonons

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

• Hanaul Noh,
• Alfredo J. Diaz and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 579–589, doi:10.3762/bjnano.8.62

• modification of unidentified surface aggregates. The aggregates are characterized electrically by Kelvin probe force microscopy and conductive atomic force microscopy (C-AFM), whereby the correlation between local electrical potential and current confirms a defective charge transport. Bimodal AFM modification

• of PSCs [15], thus providing insights into the operating mechanism of PSCs. Among all the available modes of AFM, conductive AFM (C-AFM) and Kelvin probe force microscopy (KPFM) are the most widely used for PSC research, since the measured current and electrical potential can reveal local charge

• confirms that the aggregates exist on top of the solar cell structure, and is used to remove them and to reveal the underlying active layer. The systematic analysis of the surface aggregates suggests that the structure consists of PCBM molecules. Keywords: conductive atomic force microscopy; Kelvin probe

Scanning probe microscopy studies on the adsorption of selected molecular dyes on titania

• Jakub S. Prauzner-Bechcicki,
• Lukasz Zajac,
• Piotr Olszowski,
• Res Jöhr,
• Antoine Hinaut,
• Thilo Glatzel,
• Bartosz Such,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2016, 7, 1642–1653, doi:10.3762/bjnano.7.156

• results, the next step should be aimed on monitoring the influence of the oxygen vacancies density on the averaged level alignment between a semiconducting substrate and a full organic layer. Another method used to understand the molecule-substrate interactions is Kelvin probe force microscopy (KPFM

• microscopies, it is indispensable to use other techniques such as Kelvin probe force microscopy, which allows measuring the local work function with high resolution. Such a measurement may shed some light on fundamental processes taking place in an organic DSSC upon photon absorption. Quite often, in

High-resolution noncontact AFM and Kelvin probe force microscopy investigations of self-assembled photovoltaic donor–acceptor dyads

• Benjamin Grévin,
• Pierre-Olivier Schwartz,
• Laure Biniek,
• Martin Brinkmann,
• Nicolas Leclerc,
• Elena Zaborova and
• Stéphane Méry

Beilstein J. Nanotechnol. 2016, 7, 799–808, doi:10.3762/bjnano.7.71

• dyads are used as model nanostructured heterojunctions for local investigations by noncontact atomic force microscopy (nc-AFM) and Kelvin probe force microscopy (KPFM). With the aim to probe the photo-induced charge carrier generation, thin films deposited on transparent indium tin oxide substrates are

• elementary building block level. Keywords: donor–acceptor co-oligomers; donor–acceptor lamellae; donor–acceptor-ordered bulk heterojunction; Kelvin probe force microscopy (KPFM); noncontact atomic force microscopy (nc-AFM); organic photovoltaics; surface photo-voltage (SPV); Introduction Nowadays, with

• ) materials, arranged in interpenetrated networks at the 10 nm scale to efficiently separate the excitons into free charges at the D–A interface. In the past decade, several studies demonstrated that Kelvin probe force microscopy (KPFM) can be powerfully combined with atomic force microscopy (AFM) to

Large area scanning probe microscope in ultra-high vacuum demonstrated for electrostatic force measurements on high-voltage devices

• Urs Gysin,
• Thilo Glatzel,
• Thomas Schmölzer,
• Adolf Schöner,
• Sergey Reshanov,
• Holger Bartolf and
• Ernst Meyer

Beilstein J. Nanotechnol. 2015, 6, 2485–2497, doi:10.3762/bjnano.6.258

• measurements, such as Kelvin probe force microscopy, scanning capacitance force microscopy, scanning spreading resistance microscopy, and also electrostatic force microscopy at higher harmonics. The instrument incorporates beside a standard beam deflection detection system a closed loop scanner with a scan

• range of 100 μm in lateral and 25 μm in vertical direction as well as an additional fibre optics. This enables the illumination of the tip–sample interface for optically excited measurements such as local surface photo voltage detection. Results: We present Kelvin probe force microscopy (KPFM

• the benefit of surface photo voltage measurements, we analysed the contact potential difference of a silicon carbide p/n-junction under illumination. Keywords: copper alloy; electrostatic force microscopy; high-voltage device; Kelvin probe force microscopy; silicon carbide (SiC); surface photo

Kelvin probe force microscopy for local characterisation of active nanoelectronic devices

• Tino Wagner,
• Hannes Beyer,
• Patrick Reissner,
• Philipp Mensch,
• Heike Riel,
• Bernd Gotsmann and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2015, 6, 2193–2206, doi:10.3762/bjnano.6.225

• Kelvin probe force microscopy (FM-KFM) is the method of choice for high resolution measurements of local surface potentials, yet on coarse topographic structures most researchers revert to amplitude modulated lift-mode techniques for better stability. This approach inevitably translates into lower

• modulation; Kalman filter; Kelvin probe force microscopy; sidebands; Introduction Device performance of current nanoelectronic devices, and even more so of potential future generations including nanowires or molecular junctions, critically depends on transport properties varying on a length scale of a few

• nanometres only in the active channel or at electrode interfaces. Methods for local electronic characterisation, providing accurate measurements with nanometre spatial resolution, are in very high demand, but have been lagging behind the technological requirements. Kelvin probe force microscopy (KFM) is an

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

• force microscopy [8] are presented as well as molecular structures such as the self-assembly of multidentate organothiols onto Au(111), which were studied in situ by using scanning probe nanolithography and time-lapse AFM [9]. Patterns of thiol-based self-assembled monolayers for the site-selective

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