Article
Chemistry, Multidisciplinary
Daniel Martin-Jimenez, Michael G. Ruppert, Alexander Ihle, Sebastian Ahles, Hermann A. Wegner, Andre Schirmeisen, Daniel Ebeling
Summary: This study analyzes the suitability of qPlus sensors for modern multifrequency AFM techniques and demonstrates their ability to achieve submolecular resolution imaging. The results show that using torsional and flexural higher eigenmodes can produce good imaging results and reveal specific contrast features.
Article
Chemistry, Physical
Ryan M. Khan, Martin Rejhon, Yanxiao Li, Nitika Parashar, Elisa Riedo, Ryan R. Wixom, Frank W. DelRio, Remi Dingreville
Summary: As the field of low-dimensional materials continues to grow, there is a need for techniques to characterize the mechanical properties of these materials at the nanoscale. This paper presents a modulated nanomechanical measurement technique based on atomic-force microscopy, which enables non-destructive measurements of the elasticity of ultra-thin materials with high resolution. The technique is used to study the stiffness dependence of graphene thin films and discover a peak transverse modulus in two-layer graphene.
Article
Physics, Applied
Abhilash Chandrashekar, Pierpaolo Belardinelli, Stefano Lenci, Urs Staufer, Farbod Alijani
Summary: This study successfully increased the sensitivity of higher harmonics of an atomic force microscope cantilever through dynamic mode coupling, achieving tuning of harmonic frequencies while reducing sample indentation. The results of the study indicate that nonlinear mode coupling is one of the reasons for the increase in the amplitude of higher harmonics.
PHYSICAL REVIEW APPLIED
(2021)
Article
Materials Science, Multidisciplinary
Wei Chen, Shanpeng Li, Zhiguang Guo
Summary: By studying the water-collection characteristics of natural spider silk, a nylon mesh with graded structures was fabricated using a simple spraying method and etching process. The unique wettability on the interface allows water drops to achieve mutual converging and fast downward transport. Additionally, fog flow simulation was conducted to analyze the velocity and pressure states in water collection, promoting the development of nylon mesh in water collection applications.
Article
Nanoscience & Nanotechnology
Nadav Zimron-Politi, Ryan C. Tung
Summary: In this paper, we validate an experimental model of contact resonance atomic force microscopy designed for sensors with long, massive tips. We develop a new technique and graphical method for identifying unknown system parameters and experimentally validate both the technique and the contact resonance model. Our contact resonance experimental measurements show a minimal error of 1.4%-4.5% compared to values obtained from nanoindentation, demonstrating the accuracy of the new model and parameter identification technique.
Article
Chemistry, Multidisciplinary
Benjamin Mallada, Qifan Chen, Taras Chutora, Ana Sanchez-Grande, Borja Cirera, Jose Santos, Nazario Martin, David Ecija, Pavel Jelinek, Bruno de la Torre
Summary: This study reveals that deliberately introducing atomic-scale defects into a specific anthracene-ethynylene pi-conjugated polymer can modify its inherent electronic and magnetic properties, affecting the material's performance. The results demonstrate a higher likelihood of forming low-dimensional defects at specific sites in polymers, offering new possibilities for engineering macroscopic defects in surface-synthesized conjugated polymers.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Physics, Applied
Shiquan Lin, Zhong Lin Wang
Summary: Inspired by TENG, scanning TENG is proposed for local surface charge density measurement using atomic force microscopy. The technique taps a conductive tip above a charged dielectric surface to induce an AC, with Fourier analysis showing a linear relation to surface charge density. Results demonstrate its power in probing nanoscale charge transfer in contact-electrification.
APPLIED PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Rimpi Kumari, Divya Gupta, Annu Sharma, Rahul Singhal, Sanjeev Aggarwal
Summary: In this study, surface patterning of LDPE polymeric films was investigated using oblique argon ion irradiation, revealing the influence of incident angle on the morphology of the patterns and their correlation with disordering parameters from deconvoluted Raman spectra. These patterned polymeric substrates are suitable for applications such as cell growth and bioengineering.
Article
Physics, Multidisciplinary
Arindam Phani, Ho Sang Jung, Seonghwan Kim
Summary: Phase-contrast in tapping-mode atomic force microscopy has traditionally been interpreted using homogeneous distributions that ignore fluctuations, but recent research challenges this assumption by revealing heterogeneous contributions induced by the tip. At smaller tapping amplitudes, transitional heterogeneous losses emerge as the dominant mechanism outweighing homogeneous losses, providing a more accurate characterization of soft materials. This understanding of loss pathways can offer insights into the bio-physical origins of heterogeneities in soft-bio-matter.
COMMUNICATIONS PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Nathaniel Prine, Zhiqiang Cao, Song Zhang, Tianyu Li, Changwoo Do, Kunlun Hong, Camille Cardinal, Travis L. Thornell, Sarah E. Morgan, Xiaodan Gu
Summary: Atomic-force microscopy coupled with infrared spectroscopy (AFM-IR) simultaneously maps surface morphology and chemical composition of thin-film polymer blends and composites. Overlapping infrared absorption bands between different species make quantitative analysis challenging. Isotope labeling with carbon-deuterium vibration allows distinguishing blend phases and enables nanoscale domain composition analysis.
Article
Engineering, Manufacturing
L. Angeloni, M. Ganjian, M. Nouri-Goushki, M. J. Mirzaali, C. W. Hagen, A. A. Zadpoor, L. E. Fratila-Apachitei, M. K. Ghatkesar
Summary: This study introduces two atomic force microscopy methods for determining the mechanical characteristics of individual micro- and nanopillars without the use of SEM. Case studies on nanopillars fabricated using additive manufacturing methods showed consistent results, confirming the efficacy of the proposed methods.
ADDITIVE MANUFACTURING
(2021)
Article
Chemistry, Analytical
Xinyu Li, Li Zhao, Rongrong Feng, Xiaowei Du, Zelin Guo, Yu Meng, Yulan Zou, Wenchao Liao, Qiyuan Liu, Yaohuan Sheng, Gaowei Zhao, Haijian Zhong, Weidong Zhao
Summary: Using atomic force microscopy, it was found that Na(V)1.5 is irregularly distributed on the surfaces of both normal and cancer breast cells, with higher expression on cancer cells. The stability of the Na(V)1.5-antibody complex is higher on normal breast cells compared to cancer breast cells. These findings provide insights into the interactions of ion channel-antibody systems and the role of sodium channels in tumor metastasis and invasion.
ANALYTICAL METHODS
(2023)
Article
Nanoscience & Nanotechnology
Keivan Asadi, Junghoon Yeom, Hanna Cho
Summary: Investigating internal resonance (IR) mechanisms in micro/nanoresonators reveals that intermodal coupling between second and third flexural modes in asymmetric structures provides an optimal condition for strong IR, with high energy transfer to the resonated mode. This study introduces design strategies that can be easily integrated into typical micro/nanoelectromechanical systems, offering potential for paradigm-shifting applications in micro/nanosystems.
MICROSYSTEMS & NANOENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Paolo Pellegrino, Isabella Farella, Mariafrancesca Cascione, Valeria De Matteis, Alessandro Paolo Bramanti, Antonio Della Torre, Fabio Quaranta, Rosaria Rinaldi
Summary: In recent years, Atomic Force Microscope (AFM)-based nanolithography techniques have become increasingly powerful. However, conventional methods are inefficient, have low pattern formation rates, and are complex to execute. In this study, we developed a simple and effective nanopatterning technique called Pulse-Atomic Force Lithography (P-AFL), which enabled us to pattern 2.5D nanogrooves on a thin polymer layer with sub-nanometre resolution, high accuracy, and reproducibility. We investigated the effects of P-AFL parameters on the morphology of 2.5D nanostructures and optimized the nanolithography process to achieve unconventional shape nanostructures with high accuracy and fidelity.
Article
Chemistry, Multidisciplinary
Shinichiro Ido, Kei Kobayashi, Noriaki Oyabu, Yoshiki Hirata, Kazumi Matsushige, Hirofumi Yamada
Summary: Water structuring on the outer surface of protein molecules, known as the hydration shell, is crucial for the biological activities of protein molecules in vivo. The three-dimensional force mapping technique has been successfully used to investigate the molecular-scale hydration structure of native purple membrane patches.
Article
Materials Science, Paper & Wood
Binbin Lin, Julia Auernhammer, Jan-Lukas Schaefer, Tobias Meckel, Robert Stark, Markus Biesalski, Bai-Xiang Xu
Summary: This study focuses on the mechanical properties of fibers and fiber networks under humidity influence, investigating parameters such as fiber elasticity, hygroscopic expansion, and network deformation and failure. The results indicate that relative humidity and fiber-fiber bonding parameters have significant effects on mechanical features. Computational insights are provided for interfiber bond damage pattern with respect to different humidity levels for further outlook.
Article
Materials Science, Multidisciplinary
Kuan Ding, Enrico Bruder, Christian Dietz, Karsten Durst, Xufei Fang
Summary: The study demonstrates that high-pressure torsion processing improves the oxidation resistance and mechanical properties of FeCr alloy with ultrafine-grained microstructure. Thin and dense oxide scales formed on top of the samples after oxidation, providing excellent protection for the metallic substrate. Nanoindentation study reveals dislocation nucleation, crack formation, and oxide scale penetration events during indentation.
Article
Chemistry, Physical
Raphael Poulain, Jochen Rohrer, Yannick Hermans, Christian Dietz, Joachim Brotz, Joris Proost, Marian Chatenet, Andreas Klein
Summary: The interaction between water and oriented NiO films was studied using a combination of photoelectron spectroscopy, in situ sample preparation, and electrochemical measurements. The exposure to room temperature water induced a more positive surface charge on the (110)- and (111)-oriented films compared to NiO(100), which was attributed to dissociative adsorption of water and removal of oxygen. This explains the role of water as an electron donor on oxide surfaces.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Carolin Proessl, Markus Kuebler, Stephen Paul, Lingmei Ni, Simon-Johannes Kinkelin, Nils Heppe, Klaus Eberhardt, Christopher Geppert, Wolfram Jaegermann, Robert W. Stark, Michael Bron, Ulrike Kramm
Summary: This study explored the feasibility of stabilizing FeNC catalysts with small quantities of Ir to suppress the carbon oxidation reaction and promote the oxygen evolution reaction. Various techniques including Fe-57 Mossbauer spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscopy were used to investigate the impact on structure and morphology. The results indicated a suppression of the carbon oxidation reaction, however, further optimization is necessary for fuel cell applications.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Marcus Einert, Maximilian Mellin, Niloufar Bahadorani, Christian Dietz, Stefan Lauterbach, Jan P. Hofmann
Summary: In this study, a mesoporous thin film of high-entropy spinel oxide was successfully prepared and investigated for its physicochemical and (photo-) electrochemical properties. The mesoporous structure significantly enhanced the catalytic activity and showed potential for solar water reduction and oxygen evolution reactions.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Multidisciplinary Sciences
Alena K. Bell, Jonas Kind, Maximilian Hartmann, Benjamin Kresse, Mark V. Hoefler, Benedikt B. Straub, Guenter K. Auernhammer, Michael Vogel, Christina M. Thiele, Robert W. Stark
Summary: Understanding the evaporation process of binary sessile droplets is crucial for optimizing technical processes. This study employs confocal Raman microscopy and spatially resolved NMR spectroscopy to measure the concentration gradients in evaporating droplets on a hydrophobic surface.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Multidisciplinary Sciences
Anna L. Eichhorn, Christian Dietz
Summary: Combined in-plane and out-of-plane multifrequency atomic force microscopy techniques have been used to analyze the spatial differences of sample surfaces at the atomic scale. The lateral eigenmode provides information on the shear modulus, while the torsional eigenmode reveals local friction forces between the tip and the sample. The full set of elastic constants of graphite can be determined from combined in-plane and out-of-plane multifrequency atomic force microscopy.
SCIENTIFIC REPORTS
(2022)
Article
Nanoscience & Nanotechnology
Q. K. Muhammad, H. Bishara, L. Porz, C. Dietz, M. Ghidelli, G. Dehm, T. Froemling
Summary: It has been demonstrated that doping-like properties can be achieved in functional ceramics through the introduction of dislocations. This study provides a rationalization of the electrical properties of dislocations through experimental measurements and modeling, and elucidates the significance of dislocation-tuned functionality in ceramics.
MATERIALS TODAY NANO
(2022)
Article
Chemistry, Physical
Anna L. Eichhorn, Marvin Hoffer, Christian Dietz
Summary: Graphene and graphite are materials that display friction anisotropy, which is likely caused by adsorbates aligning on graphitic surfaces. This study analyzed the evolution of adsorbates on a few-layer graphene-/graphite-flake using multifrequency force microscopy. The findings showed that friction anisotropy was observable at distinct areas of the flake after 14 days of storage, indicating different types of adsorbates. High-resolution imaging revealed that friction anisotropy occurred even on areas completely covered with adsorbates. Furthermore, the removal of adsorbate material eliminated friction anisotropy, confirming its adsorbate-driven nature on graphitic surfaces.
Article
Chemistry, Physical
Frank Hartmann, Martin Bitsch, Bart-Jan Niebuur, Marcus Koch, Tobias Kraus, Christian Dietz, Robert W. Stark, Christopher R. Everett, Peter Mueller-Buschbaum, Oliver Janka, Markus Gallei
Summary: This study synthesized a high-molecular-weight polystyrene-b-poly(methyl methacrylate) block copolymer as a soft matrix to fabricate nanocomposites containing magnetic nanoparticles. The influence of different ratios of PMMA-coated FePt nanoparticles on the self-assembled morphology was investigated. Statistical analysis revealed that the particles mainly self-assembled inside the PMMA phase at low particle concentrations, while higher particle ratios had a negative effect on the morphology. The magnetic addressability of the nanoparticles inside the nanocomposite films was confirmed using bimodal magnetic force microscopy.
Article
Chemistry, Multidisciplinary
Anna L. Eichhorn, Marvin Hoffer, Katharina Bitsch, Christian Dietz
Summary: The challenge of preparing adsorbate-free graphene with well-defined layer numbers is important for fabricating graphene-based nanodevices. Oxygen-plasma treatment of few-layer graphene/graphite flakes can tailor the layer number, but adsorbates inevitably deposit on their surfaces in ambient air. This study examines the removal/etching mechanism of individual graphene layers through stepwise oxygen-plasma treatment and analyzes the evolution of adsorbates and defects using atomic force microscopy and Raman spectroscopy. The results demonstrate the potential for efficient cleaning of graphitic surfaces and ablation of individual graphene layers.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Physical
Katrin Walter, Jan Bourquin, Anahid Amiri, Niklas Scheer, Martin Dehnert, Anna Lisa Eichhorn, Christian Dietz
Summary: Directly sensing focal adhesions and cell-cell contacts with a force sensor can provide information on the migration and invasion potential of cells. The technique quantifies the lateral forces of anchoring points and reveals local lateral forces of 1.0-1.5 nN for focal adhesions and slightly higher values at cell-cell contact interfaces. This method has the potential to improve our understanding of the relationship between mechanical properties of cell connections and disease states in the future.
Article
Polymer Science
Lea Gemmer, Bart-Jan Niebuur, Christian Dietz, Daniel Rauber, Martina Plank, Florian V. Friess, Volker Presser, Robert W. Stark, Tobias Kraus, Markus Gallei
Summary: Hierarchically porous block copolymer (BCP) membranes have been successfully developed via the self-assembly and non-solvent induced phase separation (SNIPS) process, leading to improved mechanical properties of the membranes and potential applications.
Article
Materials Science, Biomaterials
Anna Fritschen, Alena K. Bell, Inga Koenigstein, Lukas Stuehn, Robert W. Stark, Andreas Blaeser
Summary: Organs-on-a-Chip (OOCs) have been widely used in studying 3D cell organization, cell-cell interactions, and tissue response to drugs. This study focuses on the analysis of different resin systems in comparison to traditional materials used in cell culture and microfluidics. The results show that DLP-printing is a mature technology for OOCs and can be used in extensive research.
BIOMATERIALS SCIENCE
(2022)
Article
Chemistry, Physical
Marcus Einert, Maximilian Mellin, Niloufar Bahadorani, Christian Dietz, Stefan Lauterbach, Jan P. Hofmann
Summary: The study presents the preparation and characterization of mesoporous thin films of high-entropy spinel oxide on conductive substrates, showing potential applications in both photo-electrochemical and electrochemical fields. The mesoporous high-entropy oxide demonstrated improved catalytic activity compared to dense films, attributed to an increased number of catalytically active sites.
ACS APPLIED ENERGY MATERIALS
(2022)
