Dual-heterodyne Kelvin probe force microscopy

• Benjamin Grévin,
• Fatima Husainy,
• Dmitry Aldakov and
• Cyril Aumaître

Beilstein J. Nanotechnol. 2023, 14, 1068–1084, doi:10.3762/bjnano.14.88

• mode (DHe-KPFM spectroscopy), and 2D dynamic images can be acquired in data cube mode. The capabilities of DHe-KPFM in terms of time-resolved measurements, surface photovoltage (SPV) imaging, and detection of weak SPV signals are demonstrated through a series of experiments on difference surfaces: a

• ; intermodulation; KPFM; nc-AFM; surface photovoltage; time-resolved measurements; Introduction Kelvin probe force microscopy (KPFM) is a well-known variant of AFM that allows probing at the nanoscale the electrostatic landscape on the surface of a sample by measuring the so-called contact potential difference

• ). Working under modulated illumination also allows direct SPV measurements using special modulation/demodulation schemes, such as the one recently proposed by Miyazaki and co-workers for ac-bias KPFM [6]. In addition, most time-resolved KPFM modes developed so far rely on the use of a pulsed/modulated

Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine

• Zoran M. Marković,
• Milica D. Budimir,
• Martin Danko,
• Dušan D. Milivojević,
• Pavel Kubat,
• Danica Z. Zmejkoski,
• Vladimir B. Pavlović,
• Marija M. Mojsin,
• Milena J. Stevanović and
• Biljana M. Todorović Marković

Beilstein J. Nanotechnol. 2023, 14, 165–174, doi:10.3762/bjnano.14.17

• CQDs/PU samples were dipped in a solution of TEMP in ethanol at a concentration of 30 mM and irradiated with a 3 W blue LED for 12 h. Time-resolved near-infrared luminescence of O2 (1Δg) at 1270 nm after excitation by Quantel Q-smart 450 Nd YAG laser (wavelength of 355 nm, pulse length of ca. 5 ns) was

Near-infrared photoactive Ag-Zn-Ga-S-Se quantum dots for high-performance quantum dot-sensitized solar cells

• Roopakala Kottayi,
• Ilangovan Veerappan and
• Ramadasse Sittaramane

Beilstein J. Nanotechnol. 2022, 13, 1337–1344, doi:10.3762/bjnano.13.110

• efficient photoanode for QDSCs and it produces more electron–hole pairs, which helps to improve the photocurrent density. Time-resolved photoluminescence (TRPL) studies were carried out to evaluate the electrons decay time of AZGSSe/TiO2. The decay curve was fitted with a biexponential function [33] and it

Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications

• Aisha Kanwal,
• Naheed Bibi,
• Sajjad Hyder,
• Arif Muhammad,
• Hao Ren,
• Jiangtao Liu and
• Zhongli Lei

Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93

• source). They showed that luminous impurities formed as byproducts during the synthesis of CDs mostly contribute to fluorescence emission by eliminating the molecular fluorophores [133]. By using fluorescence correlation spectroscopy and time-resolved electron paramagnetic resonance spectroscopy

Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• paper, including pump-probe KPFM [13][20][43], time-resolved KPFM [11][12][44][45][46][47], fast free force recovery KPFM (G-Mode) [14][48][49][50], intermodulation electrostatic force microscopy (EFM) [42][51], and PeakForce tapping KPFM [52]. The fundamental detection sensitivity to electrostatic

Ultrafast signatures of magnetic inhomogeneity in Pd_1−xFe_x (x ≤ 0.08) epitaxial thin films

• Andrey V. Petrov,
• Sergey I. Nikitin,
• Lenar R. Tagirov,
• Amir I. Gumarov,
• Igor V. Yanilkin and
• Roman V. Yusupov

Beilstein J. Nanotechnol. 2022, 13, 836–844, doi:10.3762/bjnano.13.74

• state in the Pd1−xFex alloy at low temperatures is about 7–8 atom %. Keywords: magnetic inhomogeneities; PdFe alloy; thin epitaxial films; time-resolved magneto-optical Kerr effect; time-resolved optical spectroscopy; Introduction Superconductor-based technologies are promising for exaflop-scale

• iron at which the alloy would become magnetically homogeneous. This requires a method for detecting magnetic inhomogeneities, preferably with the possibility of being applied to thin films. We propose the use of ultrafast, time-resolved optical and magneto-optical spectroscopy methods for probing

• components, obtained from the fit of the experimental data with Equation 1 and Equation 2, are presented in Figure 3 and Figure 4 for the reflectivity and time-resolved MOKE, respectively. We note here the invariance of the amplitude As (Figure 3a) and relaxation time (Figure 3b) at T ≥ TC, and a kink in

Recent advances in nanoarchitectures of monocrystalline coordination polymers through confined assembly

• Lingling Xia,
• Qinyue Wang and
• Ming Hu

Beilstein J. Nanotechnol. 2022, 13, 763–777, doi:10.3762/bjnano.13.67

• are within the length range from 1 to 10 μm, the whole structure of the composites cannot be imaged well by electron microscopy or X-ray based imaging techniques. Second, time-resolved structural changes of the nanoarchitectonics are hard to be observed because of the complex processing environment

• . However, the time-resolved information is essential for establishing reliable mechanisms to interpret and control the formation process during the confined assembly. (a) Schematic illustration of the formation paths of MOF-2 and MOF-5 crystals. Low-order (LO) and high-order (HO) PNCs were generated under

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• perform time-resolved measurements of SPV [23][26][27]. In this paper, we propose a novel method of directly measuring the local SPV, namely AC bias Kelvin probe force microscopy (AC-KPFM), which is based on a lock-in technique (widely used in standard KPFM setups) and controls the AC bias to nullify a

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• ZnO. Time-resolved fluorescence measurements showed that increasing the Ag NP concentration in hybrid metal–ZnO nanocomposites resulted in an increase of non-radiative transitions and a decrease of the radiative emission of ZnO, indicating the energy transfer from ZnO excitons to the Ag NPs plasmons

Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review

• Viet Van Pham,
• Hong-Huy Tran,
• Thao Kim Truong and
• Thi Minh Cao

Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7

• spectroscopy (EIS) data, and the nanosecond-level time-resolved fluorescence decay spectra (Figure 11) demonstrated that the SnO2/NCDs/ZHS nanohybrid achieved low charge carrier recombination, high photoactivity, and excellent photoinduced charge transfer to the surface of the semiconductor. This study enables

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

• at the sample surface until the original state was reached again. In this way, polarization-induced, reversible surface potential changes have already been monitored for a variety of single-phase acceptor-doped ceria materials [21][22][23]. Time-resolved relaxation curves calculated from the KPFM

Open-loop amplitude-modulation Kelvin probe force microscopy operated in single-pass PeakForce tapping mode

• Gheorghe Stan and
• Pradeep Namboodiri

Beilstein J. Nanotechnol. 2021, 12, 1115–1126, doi:10.3762/bjnano.12.83

• data is limited. Moreover, the finite response time of the CL feedback (of the order of milliseconds in some cases) prevents the use of CL KPFM from observing fast electrodynamic processes. Some of these impediments are addressed in OL implementations such as time-resolved electrostatic force

Measurement of electrostatic tip–sample interactions by time-domain Kelvin probe force microscopy

• Christian Ritz,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2020, 11, 911–921, doi:10.3762/bjnano.11.76

• of the surface potential. However, it is still affected by the static contribution Δfrem. As can be seen in Equation 9, this component depends on C′′ and may change across material borders, inducing a topographic height error. The approach discussed in this paper tracks the time-resolved Δf-response

• response in the frequency shift Δf. The time-resolved measurements of both signals are shown on the right, the resulting Kelvin parabola on the left. From this information, the controller continuously estimates the contact potential difference Ulcpd, the capacitance gradient C′′, and the frequency shift

Transition from freestanding SnO₂ nanowires to laterally aligned nanowires with a simulation-based experimental design

• Jasmin-Clara Bürger,
• Sebastian Gutsch and
• Margit Zacharias

Beilstein J. Nanotechnol. 2020, 11, 843–853, doi:10.3762/bjnano.11.69

• positioned in the homogeneous downstream-oriented region. Influence of the total volumetric inflow on the development of the metal vapor concentration along the quartz tube: simulated time-resolved metal vapor concentration for a total volumetric inflow (from the right) of (a) 100 sccm, (b) 300 sccm and (c

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

• ], localized surface plasmon resonance (LSPR) [25], and plasma excitation light scattering [26][27]. Cushing et al. [28] used the time-resolved method to track these three processes by establishing a density matrix model, which allowed them to predict the theoretical maximum catalytic efficiency and

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• obtained with a Varian Cary 100 Scan device. UV–vis kinetic measurements were acquired with a Varian Cary 50 spectrometer. Photon electron spectroscopy (on air; PESA) of drop-cast particles on a glass substrate were acquired with a Riken Keiki AC-2 photoelectron spectrometer. Stationary as well as time

• -resolved photoluminescence (PL) measurements of particles suspended in toluene were obtained using a FluoTime 300 from Picoquant spectrometer. Transient absorption spectra (TAS) were measured of drop-cast particles on glass substrates. NMR measurements of particles were carried out in a Bruker Avance III

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• been implemented [26], such as in the work of Stark et al. where time-resolved transient forces between the AFM probe and the sample were obtained from the experimental data [27]. This approach was enhanced by Sahin et al. through a “torsional harmonic cantilever” [28], which combined flexural and

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

• Changqiang Yu,
• Min Wen,
• Zhen Tong,
• Shuhua Li,
• Yanhong Yin,
• Xianbin Liu,
• Yesheng Li,
• Tongxiang Liang,
• Ziping Wu and
• Dionysios D. Dionysiou

Beilstein J. Nanotechnol. 2020, 11, 407–416, doi:10.3762/bjnano.11.31

• Information File 1, Figure S1). Generally speaking, the higher the transient photocurrent density, the smaller the electrochemical impedance spectra (EIS) [33][34]. According to the time-resolved PL spectra in Figure 5d, the average fluorescence lifetime of the CuO/tourmaline composite (2.94 ns) was shortened

• ) BJH pore size distribution of the CuO, tourmaline, and CuO/tourmaline composite. (a) UV–vis diffuse reflectance spectra, (b) plots of (Ahν)2 vs hν, (c) transient photocurrent, and (d) time-resolved PL spectra of the CuO and CuO/tourmaline composite. (a) MB degradation, (b) the apparent pseudo-first

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• Benjamin Grevin Olivier Bardagot Renaud Demadrille Univ. Grenoble Alpes, CNRS, CEA, IRIG-SyMMES, 38000 Grenoble, France 10.3762/bjnano.11.24 Abstract An implementation of pump–probe Kelvin probe force microscopy (pp-KPFM) is reported that enables recording the time-resolved surface potential in

• PTB7 and PC71BM is subsequently investigated by recording point-spectroscopy curves as a function of the optical power at the cathode and by mapping 2D time-resolved images of the surface photovoltage of the bare organic active layer. Keywords: bulk heterojunctions; Kelvin probe force microscopy (KPFM

• ); organic photovoltaics; photocarrier dynamics; pump–probe configuration; time-resolved measurements; Introduction Many emerging photovoltaic technologies rely on the use of thin film materials displaying structural and/or chemical heterogeneities at the μm or nm scale. This is the case for solution

Nanosecond resistive switching in Ag/AgI/PtIr nanojunctions

• Botond Sánta,
• Dániel Molnár,
• Patrick Haiber,
• Agnes Gubicza,
• Edit Szilágyi,
• Zsolt Zolnai,
• András Halbritter and
• Miklós Csontos

Beilstein J. Nanotechnol. 2020, 11, 92–100, doi:10.3762/bjnano.11.9

• tip of a scanning probe microscope. We demonstrate stable resistive switching duty cycles and investigate the dynamical aspects of non-volatile operation in detail. The high-speed switching capabilities are explored by a custom-designed microwave setup that enables time-resolved studies of subsequent

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

• atomic force microscopy. Here, we review in detail several time-resolved EFM techniques based on non-contact atomic force microscopy, elaborating on their specific limitations and challenges. We also introduce a new experimental technique that can resolve time-varying signals well below the oscillation

• understanding local charge dynamics and composition of numerous materials with applications across many fields including energy generation and storage. Capturing time-resolved dynamic processes at ever-decreasing time and length scales has become of increased interest in recent years due to the importance of

• understanding transport properties of real-world, often heterogeneous materials relevant for energy generation and storage. A number of AFM techniques have been developed to study relevant materials including time-resolved EFM to measure photoexcited charge accumulation and charge transfer [6][9][10][11], time

Sub-wavelength waveguide properties of 1D and surface-functionalized SnO₂ nanostructures of various morphologies

• Venkataramana Bonu,
• Binaya Kumar Sahu,
• Arindam Das,
• Sankarakumar Amirthapandian,
• Sandip Dhara and
• Harish C. Barshilia

Beilstein J. Nanotechnol. 2019, 10, 379–388, doi:10.3762/bjnano.10.37

• ) indicates transitions from shallow donor levels. This broad luminescence of SnO2 (1.84 to 2.75 eV) was reported earlier and assigned to the oxygen vacancy related defect states. Time-resolved X-ray induced PL studies reveled a very fast decay lifetime (<10 ns) for PL transitions above 2.6 eV and a slow

Mechanism of silica–lysozyme composite formation unravelled by in situ fast SAXS

• Tomasz M. Stawski,
• Daniela B. van den Heuvel,
• Rogier Besselink,
• Dominique J. Tobler and
• Liane G. Benning

Beilstein J. Nanotechnol. 2019, 10, 182–197, doi:10.3762/bjnano.10.17

• at length scales from a few to hundreds of nanometres, which makes this system well-suited to be characterized by scattering methods. In particular, recent advances [25][26] in detector technology for synchrotron-based in situ and time-resolved small-angle X-ray scattering (SAXS), now allow one to

• interest can only be accessed by developing, testing and validating relevant models and bespoke data analysis methods. In this study we show step-by-step how a scattering model was developed, verified and applied to time-resolved synchrotron-based SAXS data in which we followed in situ the lysozyme-induced

• of the time-resolved scattering patterns (Figure 1A), one can distinguish four characteristic time periods (I–IV) and one region of interest (ROI V), which spanned through periods II to IV. Period I corresponds to the initial ca. 24 s of the scattering patterns of silica NPs before the injection of

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

Time-resolved universal temperature measurements using NaYF₄:Er³⁺,Yb³⁺ upconverting nanoparticles in an electrospray jet

• Kristina Shrestha,
• Arwa A. Alaulamie,
• Ali Rafiei Miandashti and
• Hugh H. Richardson

Beilstein J. Nanotechnol. 2018, 9, 2916–2924, doi:10.3762/bjnano.9.270

• temperature measurement if the entire peak shape is integrated in the calibration. Our universal calibration circumvents this problem and can be used for time-resolved applications. The temperature at the end of the Taylor cone increases due to the creation of a whispering gallery mode cavity with 980 nm

• excitation. We use time-resolved energy balance equations to support our optical temperature measurements inside the Taylor cone. We believe that the findings of this paper provide a foundation for time-resolved temperature measurements using NaYF4:Er3+,Yb3+ upconverting nanoparticles and can be used to

• understand temperature-dependent reactions such as protein unfolding inside microjet/microdroplets and microfluidic systems. Keywords: electrospray; microjet; nanothermometry; temperature measurement; time-resolved measurement; upconverting nanoparticles; Introduction There is need and interest to non