Article
Nanoscience & Nanotechnology
Songtao Hu, Xiaobao Cao, Tom Reddyhoff, Xi Shi, Zhike Peng, Andrew J. deMello, Daniele Dini
Summary: A flexibility-patterned design is proposed to enhance liquid repellency and accelerate liquid evaporation in this study, bridging the gap between rigidity-based and flexibility-based strategies in liquid-repelling applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Multidisciplinary Sciences
Fang Wang, Meijin Liu, Cong Liu, Chao Huang, Lidong Zhang, Anyang Cui, Zhigao Hu, Xuemin Du
Summary: Photo-induced charged superamphiphobic surfaces enable flexible and reliable droplet manipulation for droplet robots and bio-applications. The development of a new superamphiphobic material with the capability of photo-induced charge generation provides a novel approach for light control of droplets. The photo-induced charged surface (PICS) allows for controllable droplet motion with high velocity, unlimited distance, and multi-mode motions. This technology has potential applications in various fields, including robotics, biosensing, and biomedical applications.
NATIONAL SCIENCE REVIEW
(2023)
Article
Chemistry, Multidisciplinary
Xiaolong Yang, Kai Zhuang, Yao Lu, Xiaolei Wang
Summary: The study fabricated three-dimensional topological SLIPS with specific functions by integrating the structures from natural creatures, capable of effectively and precisely transporting droplets and manipulating droplet motion of different solutions. These created surfaces have potential applications for condensing heat transfer and droplet-based lab-on-a-chip devices.
Article
Chemistry, Multidisciplinary
Mingsheng Li, Haibao Hu, Mengzhuo Zhang, Haiyan Ding, Jun Wen, Luo Xie, Peng Du
Summary: This study proposes a novel strategy for controlling droplet motion by combining an asymmetric structure and infused lubricating oil on a vibrating substrate. The adjustment of droplet transport velocity involves an intricate interaction among the Ohnesorge number, droplet volume, and input amplitude. The findings have potential applications in the more complex manipulation of liquid droplets in microfluidic and biochemical analysis systems.
Article
Chemistry, Analytical
Siqi Qian, Han Wu, Bin Huang, Qi Liu, Yan Chen, Bo Zheng
Summary: This study presents a method for sub-micron resolution patterning of perfluorinated surfaces and its application in digital immunoassays without beads. By using negative microcontact printing and a composite stamp, polydopamine patterns are successfully fabricated on perfluorinated surfaces, enabling the creation of microspot arrays for digital assays. The high-resolution polydopamine patterned perfluorinated substrate offers a highly-sensitive and low-cost approach for digital immunoassays, showing great potential in high-throughput and digital bioassays.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Physical
Linghui Jing, Minghao Li, Yao Lu, Shuai Huang
Summary: Droplet-bubble interactions have a significant impact on various applications, but understanding the mechanisms and laws behind these interactions is a challenge due to the complex flow states. This study investigates the wetting mechanism, shape diffusion laws, and controlled impact of droplets on patterned surfaces and showcases the potential application of multilayer soap bubbles as microreactors.
SURFACES AND INTERFACES
(2023)
Article
Multidisciplinary Sciences
Danielle L. Chase, Christina Kurzthaler, Howard A. Stone
Summary: Advances in microfabrication have enabled the customization of surfaces for optimal sorting, mixing, and focusing of complex particulate suspensions in microfluidic devices. Research has shown that corrugated surfaces can manipulate particle motion effectively, with experiments and theoretical predictions revealing three-dimensional helical particle trajectories along corrugations. The interaction of disturbance flows induced by particle motion with the corrugations generates a locally transverse anisotropy of the pressure field, explaining the helical dynamics and particle drift near patterned surfaces.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Review
Multidisciplinary Sciences
Raza Gulfam, Yongping Chen
Summary: This review provides an overview of the recent progress and future prospects of wettability gradient surfaces (WGSs), including their fabrication methods, classification, characterization, and applications. WGSs are created by changing the surface energy and producing topographic micro/nanostructures, leading to new droplet wetting and dynamic behaviors. The importance of wettability gradient in inducing droplet mobility is emphasized, while also highlighting the existence of sticky and slippery regimes that affect droplet mobility. The challenges faced by WGSs are discussed, along with recommendations and the potential application of phase change materials in WGSs.
Article
Biochemical Research Methods
Weijian Liu, Xiao Luo, Changhao Chen, Guochen Jiang, Xinyu Hu, Hongjun Zhang, Minlin Zhong
Summary: The paper introduces a directional anchoring liquid-infused superamphiphobic surface (DAS) that achieves the largest sliding angle difference in a one-dimensional direction using an artificial surface, allowing for high-throughput droplet manipulation without cross-contamination. The DAS features excellent stability and functionality for handling corrosive droplets, making it a promising candidate for practical applications in various fields.
Article
Chemistry, Physical
Yanchen Wu, Mariia Kuzina, Fei Wang, Markus Reischl, Michael Selzer, Britta Nestler, Pavel A. Levkin
Summary: The hypothesis of this study is that droplet wetting on a solid substrate is affected by surface heterogeneity, and introducing patterned wettability can manipulate droplet wetting behaviors. The research found various anisotropic wetting shapes on chemically patterned substrates using analytical models, phase-field simulations, and experiments, with excellent agreement between the methods. Additionally, non-rotationally symmetric droplet shapes were observed for the first time, and anisotropic wetting shapes during quasi-equilibrium evaporation were revealed.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Thermodynamics
Hai Wang, Xin Zhao, Junfeng Wang, Zhentao Wang, Dongbao Wang, Jiameng Tian
Summary: The study developed superhydrophilic and superhydrophobic hybrid surfaces for enhancing condensation heat transfer on copper substrates. The synergistic combination of superhydrophobic and superhydrophilic surfaces was effective in improving droplet nucleation rate, coalescence control, and condensate removal efficiency. Experimental results showed that the SSH-2 surface outperformed the SSH-3 and SSH-1 surfaces in heat transfer performance, with a heat transfer coefficient 1.1 and 1.3 times higher at a surface subcooling of 7.1 K, respectively.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Joo Hyun Moon, Sangmin Lee, Chang Kyoung Choi, Seong Hyuk Lee
Summary: This study experimentally investigated the dynamic characteristics of a liquid droplet on microscale hole-patterned surfaces, comparing the effects of anodization on hydrophilicity. Results showed that the dynamic contact angle decreased with an increase in hole area fraction for the anodized surfaces, while the equilibrium and dynamic contact angles increased for non-anodized surfaces. Additionally, the dynamic contact diameter increased with area fraction and Weber number for anodized surfaces.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Chemistry, Physical
Biao Qi, Xiaolong Yang, Xiaolei Wang
Summary: This study reported the fabrication of hydrophilic patterned SLIPS on copper substrates that can achieve efficient droplet transport and fog harvest. The hydrophilic patterned SLIPS with superhydrophilic stripe array showed remarkable anisotropy in contact angle hysteresis in the parallel and perpendicular directions, which can be used for rapid and precise droplet transport.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Chemistry, Multidisciplinary
Huy Tran, Ziwen He, Pooria Pirdavari, Min Y. Pack
Summary: In order to improve the efficiency of Dynamic Wetting Condensation (DWC), researchers have been studying the distribution of droplets on the condensing surface. This study investigates the relationship between droplet shedding mechanisms and surface wettability patterning. By varying the area fraction and width of the DWC region, the study reveals changes in droplet shedding mechanisms. The results show that the sliding drop radii decrease with increasing DWC region width, while the jumping drop radii remain unchanged.
Article
Chemistry, Multidisciplinary
Ruirui Zhang, Lehua Qi, Hongcheng Lian, Jun Luo
Summary: In this study, the embedded droplet printing (EDP) method is proposed for patterning microstructures inside soft materials, exploring the impact outcome, spreading laws, and embedded morphology of droplets. The experiments revealed suppressed rebound of droplets impacting viscous surfaces, with smaller exponent values than reported previously. EDP shows promise in tailoring droplet size, depth, and morphology for creating patterned microstructures.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2022)
Article
Chemistry, Physical
Martina Tsvetanova, Alexey G. Syromyatnikov, Harold J. W. Zandvliet, Andrey L. Klavsyuk, Kai Sotthewes
Summary: In this study, scanning tunneling microscopy was used to investigate the behavior of decanethiol on Au(001) at low coverage. It was found that no ordered phases of decanethiol form on the surface. Instead, a disordered phase consisting of diffusing Au adatoms, decanethiol molecules, and/or Au-adatom-decanethiol molecule complexes was observed. Density functional theory calculations showed that the activation barrier for diffusion is lower when Au-adatom-molecule complexes are considered. These results suggest that Au adatoms expelled during the lifting of the hex reconstruction may play a role in the diffusion of thiol molecules on this surface.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Zhiguo Zhang, Bene Poelsema, Harold J. W. Zandvliet, Arie van Houselt
Summary: In this study, we utilize various techniques to investigate the critical stages of cooling of large eutectic droplets. The changes in droplet surface area and unexpected transformations in the internal structure are observed. Additionally, spaghetti-like patterns are discovered during the process when the eutectic temperature is exceeded.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Yuxuan Sun, Zhen Jiao, Harold J. W. Zandvliet, Pantelis Bampoulis
Summary: In this study, conductive atomic force microscopy was used to investigate charge carrier injection in metal-GeS nanocontacts. Three dominant injection mechanisms were identified: thermionic emission, direct tunneling, and Fowler-Nordheim tunneling. The Schottky barrier was found to be independent of the metallic tip's work function, indicating strong Fermi-level pinning.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Martina Tsvetanova, Alexey G. Syromyatnikov, Thomas van der Meer, Arie van Houselt, Harold J. W. Zandvliet, Andrey L. Klavsyuk, Kai Sotthewes
Summary: The study identified different structures of self-assembled monolayers on the Au(001) surface, including planar, striped, and disordered regions. The findings are significant for understanding the family of decanethiol formations on different gold surfaces.
Article
Physics, Fluids & Plasmas
Binglin Zeng, Yuliang Wang, Christian Diddens, Harold J. W. Zandvliet, Detlef Lohse
Summary: The paper presents a new droplet dissolution behavior, where the dissolution dynamics is controlled by local heating of the liquid, resulting in a thermal Marangoni flow around the droplet. By experimentally and theoretically studying the process, it is found that there is a relationship between the dissolution rate and the initial radius of the droplet.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Chemistry, Physical
Dennis J. Klaassen, Carolien Castenmiller, Harold J. W. Zandvliet, Pantelis Bampoulis
Summary: The Ge(110) surface can reconstruct into ordered and disordered phases with a five-membered ring of Ge atoms as the basic unit. Different surface reconstructions result in a rich electronic density of states and several surface states. Through scanning tunneling microscopy and spectroscopy, we have identified the exact origins of these surface states and connected them to either the Ge pentagons or the underlying Ge-Ge bonds. We have shown that even small fluctuations in the positions of the Ge pentagonal units can cause significant variations in the local density of states. The precise modulation of the local density of states follows the geometrical constraints of tiling Ge pentagons. These geometry-correlated electronic states provide a vast configurational landscape that could have applications in data storage and computing.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
Pantelis Bampoulis, Carolien Castenmiller, Dennis J. Klaassen, Jelle van Mil, Yichen Liu, Cheng-Cheng Liu, Yugui Yao, Motohiko Ezawa, Alexander N. Rudenko, Harold J. W. Zandvliet
Summary: We provide experimental evidence of a topological phase transition in germanene, a monoelemental quantum spin Hall insulator. By applying a critical perpendicular electric field, the topological gap is closed and germanene becomes a Dirac semimetal. Further increasing the electric field results in the opening of a trivial gap and the disappearance of metallic edge states. This switching of the topological state induced by an electric field, combined with the large gap, makes germanene suitable for room-temperature topological field-effect transistors, which could revolutionize low-energy electronics.
PHYSICAL REVIEW LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Ignaas S. M. Jimidar, Wojciech Kwiecinski, Gijs Roozendaal, E. Stefan Kooij, Han J. G. E. Gardeniers, Gert Desmet, Kai Sotthewes
Summary: Contact electrification is the exchange of electrical charges between two surfaces when they are in contact. This principle has been used in triboelectric nanogenerators (TENGs) to generate electricity. This study demonstrates the important role of water in the charge exchange process between two insulating surfaces with different wettability. The charging process is faster and acquires more charge with increasing relative humidity, especially beyond RH = 40%. The study also reveals the effect of humidity on the charging time constant. The findings contribute to the understanding of how humidity levels influence the charging process and have implications for the design of more efficient TENGs and other eco-energy harvesting devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Jort D. Verbakel, Annelies Dekker, Harold J. W. Zandvliet, Pantelis Bampoulis
Summary: By using photoconductive atomic force microscopy, we have observed a local enhancement of photoconductivity on a bilayer molybdenum disulfide on mica system, where water is present between the TMDC and the substrate. The structural phase of the water influences the doping level and thus the tunneling barrier at the nanojunction, leading to an increase in photocurrent and enhanced photopower generation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Instruments & Instrumentation
K. Vonk, J. D. Verbakel, R. Huijink, H. J. W. Zandvliet
Summary: This work demonstrates a method for electrical transport measurements on small graphene flakes using a collinear micro-four-point probe, eliminating the need for fabricating electrodes on top of the flakes. Measurements on graphene on silicon oxide and hexagonal boron nitride show good agreement with conventional transport measurements in terms of charge carrier mobilities and minimum conductivity. The possible damage caused by landing these probes on graphene is also assessed.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Letter
Chemistry, Multidisciplinary
Pantelis Bampoulis, Harold J. W. Zandvliet
Article
Engineering, Electrical & Electronic
Yorick A. Birkholzer, Kai Sotthewes, Nicolas Gauquelin, Lars Riekehr, Daen Jannis, Emma van der Minne, Yibin Bu, Johan Verbeeck, Harold J. W. Zandvliet, Gertjan Koster, Guus Rijnders
Summary: Vanadium dioxide (VO2) is a promising material for electronic and optical switching due to its semiconductor-metal transition. In this study, we demonstrate the reversible manipulation and monitoring of VO2's semiconductor-to-metal transition using a nanosized metallic probe. The direct tunneling mechanism through the VO2-metal contact is observed, and the necessary pressure for the transition decreases with temperature. Our findings also provide valuable insights into oxide electronics for future design.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Harold J. W. Zandvliet, Qirong Yao, Lijie Zhang, Pantelis Bampoulis, Zhen Jiao
Summary: This paper presents a new method to quantitatively investigate the dispersion relation of low-energy electrons in monoelemental group-IV 2D Dirac materials using conventional current-voltage spectroscopy. The method requires placing the 2D material on a substrate with a band gap and maintaining a constant density of states of the scanning tunneling microscopy tip.
Article
Chemistry, Physical
Marvin Detert, Yibo Chen, Harold J. W. Zandvliet, Detlef Lohse
Summary: Multi-component fluids with phase transitions exhibit rich physics phenomena. In this study, we investigate the transition of growth mode in plasmonic bubbles in binary liquids. The transition occurs as the three-phase contact line reaches the spinodal temperature of the more volatile component, leading to selective evaporation and the onset of convective growth.
Article
Materials Science, Multidisciplinary
Liesbeth Mulder, Carolien Castenmiller, Femke J. Witmans, Steef Smit, Mark S. Golden, Harold J. W. Zandvliet, Paul L. de Boeij, Alexander Brinkman
Summary: The electronic structure of high-quality thin films of the topological insulator (Bi0.4Sb0.6)(2)Te-3 deposited on SrTiO3 (111) has been investigated. The experimental results show similarities with theoretical calculations and reveal the presence of topological surface states and quantized dispersive bulk energy levels.
