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Wang WW, Yan H, Gu Y, Yan J, Mao BW. In Situ Electrochemical Atomic Force Microscopy: From Interfaces to Interphases. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2024; 17:103-126. [PMID: 38603469 DOI: 10.1146/annurev-anchem-061422-020428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.
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Affiliation(s)
- Wei-Wei Wang
- 1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China; ,
- 2Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen, China
| | - Hao Yan
- 1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China; ,
- 2Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen, China
| | - Yu Gu
- 1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China; ,
- 2Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen, China
| | - Jiawei Yan
- 1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China; ,
- 2Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen, China
| | - Bing-Wei Mao
- 1State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China; ,
- 2Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen, China
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2
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Weber J, Yuan Y, Pazos S, Kühnel F, Metzke C, Schätz J, Frammelsberger W, Benstetter G, Lanza M. Current-Limited Conductive Atomic Force Microscopy. ACS APPLIED MATERIALS & INTERFACES 2023; 15:56365-56374. [PMID: 37988286 DOI: 10.1021/acsami.3c10262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Conductive atomic force microscopy (CAFM) has become the preferred tool of many companies and academics to analyze the electronic properties of materials and devices at the nanoscale. This technique scans the surface of a sample using an ultrasharp conductive nanoprobe so that the contact area between them is very small (<100 nm2) and it can measure the properties of the sample with a very high lateral resolution. However, measuring relatively low currents (∼1 nA) in such small areas produces high current densities (∼1000 A/cm2), which almost always results in fast nanoprobe degradation. That is not only expensive but also endangers the reliability of the data collected because detecting which data sets are affected by tip degradation can be complex. Here, we show an inexpensive long-sought solution for this problem by using a current limitation system. We test its performance by measuring the tunneling current across a reference ultrathin dielectric when applying ramped voltage stresses at hundreds of randomly selected locations of its surface, and we conclude that the use of a current limitation system increases the lifetime of the tips by a factor of ∼50. Our work contributes to significantly enhance the reliability of one of the most important characterization techniques in the field of nanoelectronics.
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Affiliation(s)
- Jonas Weber
- Materials Science and Engineering Program, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
- Department of Electrical Engineering and Media Technology, Deggendorf Institute of Technology, Dieter-Görlitz-Platz 1, 94469 Deggendorf, Germany
- Department of Applied Physics, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Yue Yuan
- Materials Science and Engineering Program, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Sebastian Pazos
- Materials Science and Engineering Program, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Fabian Kühnel
- Department of Electrical Engineering and Media Technology, Deggendorf Institute of Technology, Dieter-Görlitz-Platz 1, 94469 Deggendorf, Germany
- Faculty of Electrical Engineering and Information Technology, University of the Bundeswehr Munich, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany
| | - Christoph Metzke
- Department of Electrical Engineering and Media Technology, Deggendorf Institute of Technology, Dieter-Görlitz-Platz 1, 94469 Deggendorf, Germany
- Department of Electrical Engineering, Helmut Schmidt University/University of the Federal Armed Forces Hamburg, Holstenhofweg 85, 22043 Hamburg, Germany
| | - Josef Schätz
- Infineon Technologies AG, Wernerwerkstraße 2, 93049 Regensburg, Germany
- Chair of Electronic Devices, RWTH Aachen University, Otto-Blumenthal-Straße 2, 52074 Aachen, Germany
| | - Werner Frammelsberger
- Department of Mechanical Engineering and Mechatronics, Deggendorf Institute of Technology, Dieter-Görlitz-Platz 1, 94469 Deggendorf, Germany
| | - Günther Benstetter
- Department of Electrical Engineering and Media Technology, Deggendorf Institute of Technology, Dieter-Görlitz-Platz 1, 94469 Deggendorf, Germany
| | - Mario Lanza
- Materials Science and Engineering Program, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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Karg A, Gödrich S, Dennstedt P, Helfricht N, Retsch M, Papastavrou G. An Integrated, Exchangeable Three-Electrode Electrochemical Setup for AFM-Based Scanning Electrochemical Microscopy. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23115228. [PMID: 37299955 DOI: 10.3390/s23115228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/14/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023]
Abstract
Scanning electrochemical microscopy (SECM) is a versatile scanning probe technique that allows monitoring of a plethora of electrochemical reactions on a highly resolved local scale. SECM in combination with atomic force microscopy (AFM) is particularly well suited to acquire electrochemical data correlated to sample topography, elasticity, and adhesion, respectively. The resolution achievable in SECM depends critically on the properties of the probe acting as an electrochemical sensor, i.e., the working electrode, which is scanned over the sample. Hence, the development of SECM probes received much attention in recent years. However, for the operation and performance of SECM, the fluid cell and the three-electrode setup are also of paramount importance. These two aspects received much less attention so far. Here, we present a novel approach to the universal implementation of a three-electrode setup for SECM in practically any fluid cell. The integration of all three electrodes (working, counter, and reference) near the cantilever provides many advantages, such as the usage of conventional AFM fluid cells also for SECM or enables the measurement in liquid drops. Moreover, the other electrodes become easily exchangeable as they are combined with the cantilever substrate. Thereby, the handling is improved significantly. We demonstrated that high-resolution SECM, i.e., resolving features smaller than 250 nm in the electrochemical signal, could be achieved with the new setup and that the electrochemical performance was equivalent to the one obtained with macroscopic electrodes.
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Affiliation(s)
- Andreas Karg
- Physical Chemistry II, University of Bayreuth, 95447 Bayreuth, Germany
- Bavarian Institute for Battery Technology, University of Bayreuth, 95448 Bayreuth, Germany
| | - Sebastian Gödrich
- Physical Chemistry II, University of Bayreuth, 95447 Bayreuth, Germany
| | - Philipp Dennstedt
- Physical Chemistry II, University of Bayreuth, 95447 Bayreuth, Germany
- Bavarian Institute for Battery Technology, University of Bayreuth, 95448 Bayreuth, Germany
| | - Nicolas Helfricht
- Physical Chemistry II, University of Bayreuth, 95447 Bayreuth, Germany
| | - Markus Retsch
- Bavarian Institute for Battery Technology, University of Bayreuth, 95448 Bayreuth, Germany
- Physical Chemistry I, University of Bayreuth, 95447 Bayreuth, Germany
| | - Georg Papastavrou
- Physical Chemistry II, University of Bayreuth, 95447 Bayreuth, Germany
- Bavarian Institute for Battery Technology, University of Bayreuth, 95448 Bayreuth, Germany
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Moraille P, Abdali Z, Ramkaran M, Polcari D, Patience GS, Dorval Courchesne N, Badia A. Experimental Methods in Chemical Engineering: Atomic force microscopy—
AFM. CAN J CHEM ENG 2022. [DOI: 10.1002/cjce.24407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Zahra Abdali
- Chemical Engineering, McGill University Québec Canada
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Zheng P, He H, Gao Y, Tang P, Wang H, Peng J, Wang L, Su C, Ding S. Speeding up the Topography Imaging of Atomic Force Microscopy by Convolutional Neural Network. Anal Chem 2022; 94:5041-5047. [PMID: 35294191 DOI: 10.1021/acs.analchem.1c05056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atomic force microscopy (AFM) provides unprecedented insight into surface topography research with ultrahigh spatial resolution at the subnanometer level. However, a slow scanning rate has to be employed to ensure the image quality, which will largely increase the accumulated sample drift, thereby, resulting in the low fidelity of the AFM image. In this paper, we propose a fast imaging method which performs a complete fast Raster scanning and a slow μ-path subsampling together with a deep learning algorithm to rapidly produce an AFM image with high quality and small drift. A supervised convolutional neural network (CNN) model is trained with the slow μ-path subsampled data and its counterpart acquired with fast Raster scan. The fast speed acquired AFM image is then inputted to the well-trained CNN model to output the high quality one. We validate the reliability of this method using a silicon grids sample and further apply it to the fast imaging of a vanadium dioxide thin film. The results demonstrate that this method can largely improve the imaging speed up to 10.3 times with state-of-the-art imaging quality, and reduce the sample drift by 8.9 times in the multiframe AFM imaging of the same area. Furthermore, we prove that this method is also applicable to other scanning imaging techniques such as scanning electrochemical microscopy.
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Affiliation(s)
- Peng Zheng
- School of Aerospace Engineering, Xiamen University, Xiamen 361005, China
| | - Hao He
- School of Aerospace Engineering, Xiamen University, Xiamen 361005, China
| | - Yun Gao
- School of Aerospace Engineering, Xiamen University, Xiamen 361005, China
| | - Peiwen Tang
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.,School of Chemistry and Chemical Engineering, Ningxia University, Ningxia 750021, China
| | - Hailong Wang
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Juan Peng
- School of Chemistry and Chemical Engineering, Ningxia University, Ningxia 750021, China
| | - Lei Wang
- School of Aerospace Engineering, Xiamen University, Xiamen 361005, China
| | - Chanmin Su
- Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China
| | - Songyuan Ding
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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Atomistic insights into highly active reconstructed edges of monolayer 2H-WSe 2 photocatalyst. Nat Commun 2022; 13:1256. [PMID: 35273184 PMCID: PMC8913837 DOI: 10.1038/s41467-022-28926-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 02/16/2022] [Indexed: 11/17/2022] Open
Abstract
Ascertaining the function of in-plane intrinsic defects and edge atoms is necessary for developing efficient low-dimensional photocatalysts. We report the wireless photocatalytic CO2 reduction to CH4 over reconstructed edge atoms of monolayer 2H-WSe2 artificial leaves. Our first-principles calculations demonstrate that reconstructed and imperfect edge configurations enable CO2 binding to form linear and bent molecules. Experimental results show that the solar-to-fuel quantum efficiency is a reciprocal function of the flake size. It also indicates that the consumed electron rate per edge atom is two orders of magnitude larger than the in-plane intrinsic defects. Further, nanoscale redox mapping at the monolayer WSe2–liquid interface confirms that the edge is the most preferred region for charge transfer. Our results pave the way for designing a new class of monolayer transition metal dichalcogenides with reconstructed edges as a non-precious co-catalyst for wired or wireless hydrogen evolution or CO2 reduction reactions. Systematically study of in-plane intrinsic defects and edge atoms is important to guide the design of low-dimensional photocatalysts. Here the authors investigate photocatalytic CO2 reduction to CH4 over reconstructed edge atoms of monolayer semiconducting WSe2.
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Karg A, Rößler T, Mark A, Markus P, Lauster T, Helfricht N, Papastavrou G. A Versatile and Simple Approach to Electrochemical Colloidal Probes for Direct Force Measurements. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:13537-13547. [PMID: 34752120 DOI: 10.1021/acs.langmuir.1c01557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The colloidal probe technique, which is based on micrometer-sized colloidal particles that are attached to the end of a cantilever, revolutionized direct force measurements by atomic force microscopy (AFM). Its major advantages are a defined interaction geometry and a high force sensitivity. Here, we present a versatile and simple approach for preparing spherical electrodes in the micrometer range on an otherwise insulated AFM cantilever. Thereby, it becomes possible to combine direct force measurements and potentiostatic control of the probe for various types of electrode materials. Two examples for the use of such electrochemical colloidal probes (eCP) are presented: First, on soft, conductive films of poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS) the adhesion behavior was studied. The current through the contact area between the probe and film remained constant until the jump-out of contact, indicating a constant geometrical contact area. Second, the long-range forces due to diffuse layer overlap between an eCP and a glass surface have been determined as a function of the externally applied potential. The resulting interaction force profiles are in good agreement with those calculated based on charge regulation and solutions of the full Poisson-Boltzmann equation.
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Affiliation(s)
- Andreas Karg
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
- Bavarian Center for Battery Technology, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Tamino Rößler
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Andreas Mark
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Paul Markus
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Tobias Lauster
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Nicolas Helfricht
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Georg Papastavrou
- Physical Chemistry II, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany
- Bavarian Center for Battery Technology, Universitätsstrasse 30, 95447 Bayreuth, Germany
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Nie W, Zhu Q, Gao Y, Wang Z, Liu Y, Wang X, Chen R, Fan F, Li C. Visualizing the Spatial Heterogeneity of Electron Transfer on a Metallic Nanoplate Prism. NANO LETTERS 2021; 21:8901-8909. [PMID: 34647747 DOI: 10.1021/acs.nanolett.1c03529] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The involvement between electron transfer (ET) and catalytic reaction at the electrocatalyst surface makes the electrochemical process challenging to understand and control. Even ET process, a primary step, is still ambiguous because it is unclear how the ET process is related to the nanostructured electrocatalyst. Herein, locally enhanced ET current dominated by mass transport effect at corner and edge sites bounded by {111} facets on single Au triangular nanoplates was clearly imaged. After decoupling mass transport effect, the ET rate constant of corner sites was measured to be about 2-fold that of basal {111} plane. Further, we demonstrated that spatial heterogeneity of local inner potential differences of Au nanoplates/solution interfaces plays a key role in the ET process, supported by the linear correlation between the logarithm of rate constants and the potential differences of different sites. These results provide direct images for heterogeneous ET, which helps to understand and control the nanoscopic electrochemical process and electrode design.
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Affiliation(s)
- Wei Nie
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qianhong Zhu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuying Gao
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Ziyuan Wang
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yong Liu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Xun Wang
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Ruotian Chen
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Fengtao Fan
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Can Li
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, The Collaborative Innovation Centre of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
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Abstract
Mass-transport-limited catalysis and membrane transport can be characterized by concentration profiles surrounding active surfaces. Scanning electrochemical microscopy (SECM) is a tool that has been used to measure concentration profiles; however, the presence and geometry of the tip can distort these profiles due to hindered diffusion, which in turn alters chemical behavior at the catalytic surface. To fully characterize the behavior of surface features such as catalytic sites, it is essential to account for and analytically remove the effect of tip presence. In this work, atomic force microscopy-based SECM (AFM-SECM) measurements over poly(tetrafluoroethylene) (PTFE) and gold electrode surfaces are used to measure negative and positive-feedback approach curves, respectively. By inversely fitting these approach curves with a finite element method (FEM) model, we derive kinetic and geometric tip parameters that characterize the effect of tip presence. Tip effects may be removed in the model to estimate concentration profiles and reaction properties for the case where no tip is present. A maximum 120% increase in the concentration at one tip radii above the surface is observed due to the presence of the tip, where the concentration field is compressed vertically, in proportion to surface feature size and tip separation. Conical AFM-SECM tips, with a higher ratio of tip height to the base size, introduce less concentration distortion than disk-shaped AFM-SECM tips.
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Affiliation(s)
- Alex Mirabal
- Department of Chemical Engineering and Material Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Scott Calabrese Barton
- Department of Chemical Engineering and Material Science, Michigan State University, East Lansing, Michigan 48824, United States
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Pan H, Chen Y, Pang W, Sun H, Li J, Lin Y, Kolosov O, Huang Z. Complementary sample preparation strategies (PVD/BEXP) combining with multifunctional SPM for the characterizations of battery interfacial properties. MethodsX 2021; 8:101250. [PMID: 34434773 PMCID: PMC8374284 DOI: 10.1016/j.mex.2021.101250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/22/2021] [Indexed: 11/17/2022] Open
Abstract
The cathode/anode-electrolyte interfaces in lithium/sodium ion batteries act as the “gate” for the ion exchange between the solid electrode and liquid electrolyte. Understanding the interfacial properties of these solid-liquid interfaces is essential for better design high-performance lithium/sodium ion batteries. Here, we provide a novel method for studying solid-liquid interfacial properties of battery materials through combining physical vapor deposition (PVD) and beam-exit cross-sectional polishing (BEXP) followed by controlled environment multifunctional Scanning Probe Microscope (SPM). In this method, commercial battery materials can be either directly grown on the current collector substrates, or polished by obliqued Ar-ion beams to get a nanoscale flat surface which allows the multifunctional SPM to study sample directly in the liquid electrolyte or in protective oxygen/H2O free environment. This approach allows to investigate wide range of interfacial properties, including surface morphology, internal cracks, mechanical properties, electronic/ionic conductivity and surface potential, with nanoscale resolution in-operando during the battery cycles as well as post-mortem.PVD and novel BEXP methods were introduced to prepare battery powder materials as perfect specimens for nanoscale SPM characterization. Various physical/chemical properties of battery materials can be probed on the as-prepared specimens under liquid electrolyte using in situ/operando SPM techniques. Ex situ/post-mortem analyses based on the controlled environment multifunction SPM characterizations can be achieved in the BEXP polished degradation battery electrodes.
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Affiliation(s)
- Handian Pan
- College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China
| | - Yue Chen
- College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China
- Physics Department and Materials Science Institute, Lancaster University, LA1 4YB, UK
- Corresponding authors at: College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China.
| | - Wenhui Pang
- Bruker Nano Surfaces and Metrology Division, Bruker (Beijing) Scientific Technology Co. Ltd., Beijing 100081, China
| | - Hao Sun
- Bruker Nano Surfaces and Metrology Division, Bruker (Beijing) Scientific Technology Co. Ltd., Beijing 100081, China
| | - Jiaxin Li
- College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China
- Corresponding authors at: College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China.
| | - Yingbin Lin
- College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy, Fuzhou 350117, China
| | - Oleg Kolosov
- Physics Department and Materials Science Institute, Lancaster University, LA1 4YB, UK
| | - Zhigao Huang
- College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China
- Fujian Provincial Collaborative Innovation Centre for Advanced High-Field Superconducting Materials and Engineering, Fuzhou 350117, China
- Corresponding authors at: College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou 350117, China.
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Cancer Nanopharmaceuticals: Physicochemical Characterization and In Vitro/In Vivo Applications. Cancers (Basel) 2021; 13:cancers13081896. [PMID: 33920840 PMCID: PMC8071188 DOI: 10.3390/cancers13081896] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/07/2021] [Accepted: 04/13/2021] [Indexed: 12/14/2022] Open
Abstract
Physicochemical, pharmacokinetic, and biopharmaceutical characterization tools play a key role in the assessment of nanopharmaceuticals' potential imaging analysis and for site-specific delivery of anti-cancers to neoplastic cells/tissues. If diagnostic tools and therapeutic approaches are combined in one single nanoparticle, a new platform called nanotheragnostics is generated. Several analytical technologies allow us to characterize nanopharmaceuticals and nanoparticles and their properties so that they can be properly used in cancer therapy. This paper describes the role of multifunctional nanoparticles in cancer diagnosis and treatment, describing how nanotheragnostics can be useful in modern chemotherapy, and finally, the challenges associated with the commercialization of nanoparticles for cancer therapy.
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12
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Li J, Shen X, Pan Y, Peng Z. Fingerprinting the Ammonia Synthesis Pathway Using Spatiotemporal Electrostatic Potential Distribution of Intermediates. ACS OMEGA 2021; 6:6292-6296. [PMID: 33718719 PMCID: PMC7948246 DOI: 10.1021/acsomega.0c05975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
It remains a research challenge in determining the catalytic reaction mechanisms primarily caused by the difficulty to experimentally identify active intermediates with current analytic characterizations. Although computational chemistry has provided an alternative approach to simulate the catalysis process and achieve insights into the reaction pathways, the simulation results would not be conclusive without experimental evidence. Herein, we investigate spatiotemporal electrostatic potential (ESP) distribution surrounding reacting molecules during the catalysis process and suggest its use as a fingerprint to help differentiate and identify active intermediates. Our ESP study of ammonia synthesis on the Ru surface shows a high spatial sensitivity of ESP distribution to molecular configuration and structure of intermediate species and only minor temporal ESP oscillation throughout the lifetime of the intermediates, which provides strong theoretical support to use ESP distribution as a new approach to characterize intermediates. With the ESP measurements at the microscale and in real-time, turning feasible, experimental identification of active intermediates and determination of reaction pathways would become possible by measuring the ESP surrounding the reacting molecules. We suggest developing ESP measurement tools to experimentally explore and unveil reaction mechanisms.
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Abstract
Layered MoS2 is considered as one of the most promising two-dimensional photocatalytic materials for hydrogen evolution and water splitting; however, the electronic structure at the MoS2-liquid interface is so far insufficiently resolved. Measuring and understanding the band offset at the surfaces of MoS2 are crucial for understanding catalytic reactions and to achieve further improvements in performance. Herein, the heterogeneous charge transfer behavior of MoS2 flakes of various layer numbers and sizes is addressed with high spatial resolution in organic solutions using the ferrocene/ferrocenium (Fc/Fc+) redox pair as a probe in near-field scanning electrochemical microscopy, i.e. in close nm probe-sample proximity. Redox mapping reveals an area and layer dependent reactivity for MoS2 with a detailed insight into the local processes as band offset and confinement of the faradaic current obtained. In combination with additional characterization methods, we deduce a band alignment occurring at the liquid-solid interface. Here, high-resolution atomic force microscopy and scanning electrochemical microscopy are used to investigate the electron transfer behaviour of layered MoS2 flakes in organic solutions, offering insights on the electronic band alignment at the solid-liquid interface.
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14
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Yu W, Fu HJ, Mueller T, Brunschwig BS, Lewis NS. Atomic force microscopy: Emerging illuminated and operando techniques for solar fuel research. J Chem Phys 2020; 153:020902. [PMID: 32668946 DOI: 10.1063/5.0009858] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Integrated photoelectrochemical devices rely on the synergy between components to efficiently generate sustainable fuels from sunlight. The micro- and/or nanoscale characteristics of the components and their interfaces often control critical processes of the device, such as charge-carrier generation, electron and ion transport, surface potentials, and electrocatalysis. Understanding the spatial properties and structure-property relationships of these components can provide insight into designing scalable and efficient solar fuel components and systems. These processes can be probed ex situ or in situ with nanometer-scale spatial resolution using emerging scanning-probe techniques based on atomic force microscopy (AFM). In this Perspective, we summarize recent developments of AFM-based techniques relevant to solar fuel research. We review recent progress in AFM for (1) steady-state and dynamic light-induced surface photovoltage measurements; (2) nanoelectrical conductive measurements to resolve charge-carrier heterogeneity and junction energetics; (3) operando investigations of morphological changes, as well as surface electrochemical potentials, currents, and photovoltages in liquids. Opportunities for research include: (1) control of ambient conditions for performing AFM measurements; (2) in situ visualization of corrosion and morphological evolution of electrodes; (3) operando AFM techniques to allow nanoscale mapping of local catalytic activities and photo-induced currents and potentials.
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Affiliation(s)
- Weilai Yu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Harold J Fu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Thomas Mueller
- Bruker Nano Surfaces, 112 Robin Hill Road, Santa Barbara, California 93111, USA
| | - Bruce S Brunschwig
- Beckman Institute, California Institute of Technology, Pasadena, California 91125, USA
| | - Nathan S Lewis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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15
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Katorova NS, Luchkin SY, Rupasov DP, Abakumov AM, Stevenson KJ. Origins of irreversible capacity loss in hard carbon negative electrodes for potassium-ion batteries. J Chem Phys 2020; 152:194704. [DOI: 10.1063/5.0003257] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Natalia S. Katorova
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
| | - Sergey Yu. Luchkin
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
| | - Dmitry P. Rupasov
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
| | - Artem M. Abakumov
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
| | - Keith J. Stevenson
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
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16
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Liu C, Han X, Yang X, Tian L, Wang Y, Wang X, Yang H, Ge Z, Hu C, Liu C, Song Z, Weng Z, Wang Z. Self-repair behaviour of the neuronal cell membrane by conductive atomic force indentation. IET Nanobiotechnol 2020; 13:891-895. [PMID: 31811756 DOI: 10.1049/iet-nbt.2019.0123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Conductive atomic force indentation (CAFI) was proposed to study the self-repair behaviour of the neuronal cell membrane here. CAFI was used to detect the changes of membrane potentials by performing the mechanical indentation on neurons with a conductive atomic force microscope. In the experiment, a special insulation treatment was made on the conductive probe, which turned out to be a conductive nanoelectrode, to implement the CAFI function. The mechanical properties of the neuronal cell membrane surface were tested and the membrane potential changes of neurons cultured in vitro were detected. The self-repair behaviour of the neuronal cell membrane after being punctured was investigated. The experiment results show that CAFI provides a new way for the study of self-repair behaviours of neuronal cell membranes and mechanical and electrical properties of living cells.
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Affiliation(s)
- Caijun Liu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Xueyan Han
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Xueying Yang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Liguo Tian
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Ying Wang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Xinyue Wang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Huanzhou Yang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Zenghui Ge
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Cuihua Hu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Chuanzhi Liu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Zhengxun Song
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Zhankun Weng
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, People's Republic of China
| | - Zuobin Wang
- JR3CN & IRAC, University of Bedfordshire, Luton LU1 3JU, UK.
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17
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Synchronous Electrical Conductance‐ and Electron Tunnelling‐Scanning Electrochemical Microscopy Measurements. ChemElectroChem 2020. [DOI: 10.1002/celc.201901721] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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18
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Atomic force microscopy - Scanning electrochemical microscopy (AFM-SECM) for nanoscale topographical and electrochemical characterization: Principles, applications and perspectives. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2019.135472] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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19
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Laskowski FAL, Oener SZ, Nellist MR, Gordon AM, Bain DC, Fehrs JL, Boettcher SW. Nanoscale semiconductor/catalyst interfaces in photoelectrochemistry. NATURE MATERIALS 2020; 19:69-76. [PMID: 31591528 DOI: 10.1038/s41563-019-0488-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/18/2019] [Indexed: 05/12/2023]
Abstract
Semiconductor structures (for example, films, wires, particles) used in photoelectrochemical devices are often decorated with nanoparticles that catalyse fuel-forming reactions, including water oxidation, hydrogen evolution or carbon-dioxide reduction. For high performance, the catalyst nanoparticles must form charge-carrier-selective contacts with the underlying light-absorbing semiconductor, facilitating either hole or electron transfer while inhibiting collection of the opposite carrier. Despite the key role played by such selective contacts in photoelectrochemical energy conversion and storage, the underlying nanoscale interfaces are poorly understood because direct measurement of their properties is challenging, especially under operating conditions. Using an n-Si/Ni photoanode model system and potential-sensing atomic force microscopy, we measure interfacial electron-transfer processes and map the photovoltage generated during photoelectrochemical oxygen evolution at nanoscopic semiconductor/catalyst interfaces. We discover interfaces where the selectivity of low-Schottky-barrier n-Si/Ni contacts for holes is enhanced via a nanoscale size-dependent pinch-off effect produced when surrounding high-barrier regions develop during device operation. These results thus demonstrate (1) the ability to make nanoscale operando measurements of contact properties under practical photoelectrochemical conditions and (2) a design principle to control the flow of electrons and holes across semiconductor/catalyst junctions that is broadly relevant to different photoelectrochemical devices.
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Affiliation(s)
| | - Sebastian Z Oener
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
| | - Michael R Nellist
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
| | - Adrian M Gordon
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
| | - David C Bain
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
| | - Jessica L Fehrs
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
| | - Shannon W Boettcher
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA.
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20
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Mark A, Helfricht N, Rauh A, Xue J, Knödler P, Schumacher T, Karg M, Du B, Lippitz M, Papastavrou G. Electrokinetics in Micro-channeled Cantilevers: Extending the Toolbox for Reversible Colloidal Probes and AFM-Based Nanofluidics. Sci Rep 2019; 9:20294. [PMID: 31889103 PMCID: PMC6937245 DOI: 10.1038/s41598-019-56716-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 12/04/2019] [Indexed: 11/23/2022] Open
Abstract
The combination of atomic force microscopy (AFM) with nanofluidics, also referred to as FluidFM, has facilitated new applications in scanning ion conductance microscopy, direct force measurements, lithography, or controlled nanoparticle deposition. An essential element of this new type of AFMs is its cantilever, which bears an internal micro-channel with a defined aperture at the end. Here, we present a new approach for in-situ characterization of the internal micro-channels, which is non-destructive and based on electrochemical methods. It allows for probing the internal environment of a micro-channeled cantilever and the corresponding aperture, respectively. Acquiring the streaming current in the micro-channel allows to determine not only the state of the aperture over a wide range of ionic strengths but also the surface chemistry of the cantilever’s internal channel. The high practical applicability of this method is demonstrated by detecting the aspiration of polymeric, inorganic and hydrogel particles with diameters ranging from several µm down to 300 nm. By verifying in-situ the state of the aperture, i.e. open versus closed, electrophysiological or nano-deposition experiments will be significantly facilitated. Moreover, our approach is of high significance for direct force measurements by the FluidFM-technique and sub-micron colloidal probes.
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Affiliation(s)
- Andreas Mark
- Physical Chemistry II, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
| | - Nicolas Helfricht
- Physical Chemistry II, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany.,Bavarian Polymer Institute, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
| | - Astrid Rauh
- Physical Chemistry I, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40204, Düsseldorf, Germany
| | - Jinqiao Xue
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Patrick Knödler
- Experimental Physics III, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
| | - Thorsten Schumacher
- Experimental Physics III, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
| | - Matthias Karg
- Physical Chemistry I, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40204, Düsseldorf, Germany
| | - Binyang Du
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Markus Lippitz
- Experimental Physics III, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
| | - Georg Papastavrou
- Physical Chemistry II, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany. .,Bavarian Polymer Institute, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany.
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21
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Hosseini N, Neuenschwander M, Peric O, Andany SH, Adams JD, Fantner GE. Integration of sharp silicon nitride tips into high-speed SU8 cantilevers in a batch fabrication process. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2019; 10:2357-2363. [PMID: 31886112 PMCID: PMC6902782 DOI: 10.3762/bjnano.10.226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 11/12/2019] [Indexed: 05/31/2023]
Abstract
Employing polymer cantilevers has shown to outperform using their silicon or silicon nitride analogues concerning the imaging speed of atomic force microscopy (AFM) in tapping mode (intermittent contact mode with amplitude modulation) by up to one order of magnitude. However, tips of the cantilever made out of a polymer material do not meet the requirements for tip sharpness and durability. Combining the high imaging bandwidth of polymer cantilevers with making sharp and wear-resistant tips is essential for a future adoption of polymer cantilevers in routine AFM use. In this work, we have developed a batch fabrication process to integrate silicon nitride tips with an average tip radius of 9 ± 2 nm into high-speed SU8 cantilevers. Key aspects of the process are the mechanical anchoring of a moulded silicon nitride tip and a two-step release process. The fabrication recipe can be adjusted to any photo-processable polymer cantilever.
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Affiliation(s)
- Nahid Hosseini
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
| | - Matthias Neuenschwander
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
| | - Oliver Peric
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
| | - Santiago H Andany
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
| | - Jonathan D Adams
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
- Biophysik Department, ETH Zürich, Basel, Switzerland
| | - Georg E Fantner
- Bioengineering department, Ecole Polytechnique Fédérale de Lausanne, EPFL STI IBI-STI LBNI, Lausanne, Switzerland
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22
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Chen Y, Yu Q, Xu G, Zhao G, Li J, Hong Z, Lin Y, Dong CL, Huang Z. In Situ Observation of the Insulator-To-Metal Transition and Nonequilibrium Phase Transition for Li 1-xCoO 2 Films with Preferred (003) Orientation Nanorods. ACS APPLIED MATERIALS & INTERFACES 2019; 11:33043-33053. [PMID: 31419106 DOI: 10.1021/acsami.9b11140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
It is notoriously difficult to distinguish the stoichiometric LiCoO2 (LCO) with a O3-I structure from its lithium defective O3-II phase because of their similar crystal symmetry. Interestingly, moreover, the O3-II phase shows metallic conductivity, whereas the O3-I phase is an electronic insulator. How to effectively reveal the intrinsic mechanism of the conductivity difference and nonequilibrium phase transition induced by the lithium deintercalation is of vital importance for its practical application and development. Based on the developed technology of in situ peak force tunneling atomic force microscopy (PF-TUNA) in liquids, the phase transition from O3-I to O3-II and consequent insulator-to-metal transition of LCO thin-film electrodes with preferred (003) orientation nanorods designed and prepared via magnetron sputtering were observed under an organic electrolyte for the first time in this work. Then, studying the post-mortem LCO thin-film electrode by using ex situ time-dependent XRD and conductive atomic force microscopy, we find the phase relaxation of LCO electrodes after the nonequilibrium deintercalation, further proving the differences of the electronic conductivity and work function between the O3-I and O3-II phases. Moreover, X-ray absorption spectroscopy results indicate that the oxidation of Co ions and the increasing of O 2p-Co 3d hybridization in the O3-II phase lead to electrical conductivity improvement in Li1-xCoO2. Simultaneously, it is found that the nonequilibrium deintercalation at a high charging rate can result in phase-transition hysteresis and the O3-I/O3-II coexistence at the charging end, which is explained well by an ionic blockade model with an antiphase boundary. At last, this work strongly suggests that PF-TUNA can be used to reveal the unconventional phenomena on the solid/liquid interfaces.
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Affiliation(s)
- Yue Chen
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy , Fuzhou 350117 , China
| | - Qing Yu
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy , Fuzhou 350117 , China
| | - Guigui Xu
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy , Fuzhou 350117 , China
| | - Guiying Zhao
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices , Xiamen 361005 , China
| | - Jiaxin Li
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices , Xiamen 361005 , China
| | - Zhensheng Hong
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy , Fuzhou 350117 , China
| | - Yingbin Lin
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Engineering Technical Research Centre of Solar-Energy Conversion and Stored Energy , Fuzhou 350117 , China
| | - Chung-Li Dong
- Department of Physics , Tamkang University , 151 Yingzhuan Road , Tamsui 25137 , Taiwan
| | - Zhigao Huang
- College of Physics and Energy , Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials , Fuzhou 350117 , China
- Fujian Provincial Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices , Xiamen 361005 , China
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23
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Toca‐Herrera JL. Atomic Force Microscopy Meets Biophysics, Bioengineering, Chemistry, and Materials Science. CHEMSUSCHEM 2019; 12:603-611. [PMID: 30556380 PMCID: PMC6492253 DOI: 10.1002/cssc.201802383] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/12/2018] [Indexed: 05/12/2023]
Abstract
Briefly, herein the use of atomic force microscopy (AFM) in the characterization of molecules and (bioengineered) materials related to chemistry, materials science, chemical engineering, and environmental science and biotechnology is reviewed. First, the basic operations of standard AFM, Kelvin probe force microscopy, electrochemical AFM, and tip-enhanced Raman microscopy are described. Second, several applications of these techniques to the characterization of single molecules, polymers, biological membranes, films, cells, hydrogels, catalytic processes, and semiconductors are provided and discussed.
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Affiliation(s)
- José L. Toca‐Herrera
- Institute for Biophysics, Department of NanobiotechnologyUniversity of Natural Resources and Life Sciences Vienna (BOKU)Muthgasse 111190ViennaAustria
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24
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Laskowski FAL, Nellist MR, Qiu J, Boettcher SW. Metal Oxide/(oxy)hydroxide Overlayers as Hole Collectors and Oxygen-Evolution Catalysts on Water-Splitting Photoanodes. J Am Chem Soc 2018; 141:1394-1405. [PMID: 30537811 DOI: 10.1021/jacs.8b09449] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Solar water splitting provides a mechanism to convert and store solar energy in the form of stable chemical bonds. Water-splitting systems often include semiconductor photoanodes, such as n-Fe2O3 and n-BiVO4, which use photogenerated holes to oxidize water. These photoanodes often exhibit improved performance when coated with metal-oxide/(oxy)hydroxide overlayers that are catalytic for the water-oxidation reaction. The mechanism for this improvement, however, remains a controversial topic. This is, in part, due to a lack of experimental techniques that are able to directly track the flow of photogenerated holes in such multicomponent systems. In this Perspective, we illustrate how this issue can be addressed by using a second working electrode to make direct current/voltage measurements on the catalytic overlayer during operation in a photoelectrochemical cell. We discuss examples where the second working electrode is a thin metallic film deposited on the catalyst layer, as well as where it is the tip of a conducting atomic-force-microscopy probe. In applying these techniques to multiple semiconductors (Fe2O3, BiVO4, Si) paired with various metal-(oxy)hydroxide overlayers (e.g., Ni(Fe)O xH y and CoO xH y), we found in all cases investigated that the overlayers collect photogenerated holes from the semiconductor, charging to potentials sufficient to drive water oxidation. The overlayers studied thus form charge-separating heterojunctions with the semiconductor as well as serve as water-oxidation catalysts.
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Affiliation(s)
- Forrest A L Laskowski
- Department of Chemistry and Biochemistry , University of Oregon , Eugene , Oregon 97403 , United States
| | - Michael R Nellist
- Department of Chemistry and Biochemistry , University of Oregon , Eugene , Oregon 97403 , United States
| | - Jingjing Qiu
- Department of Chemistry and Biochemistry , University of Oregon , Eugene , Oregon 97403 , United States
| | - Shannon W Boettcher
- Department of Chemistry and Biochemistry , University of Oregon , Eugene , Oregon 97403 , United States
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25
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Bentley CL, Edmondson J, Meloni GN, Perry D, Shkirskiy V, Unwin PR. Nanoscale Electrochemical Mapping. Anal Chem 2018; 91:84-108. [PMID: 30500157 DOI: 10.1021/acs.analchem.8b05235] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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26
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Ding S, Li Z, Cheng Y, Du C, Gao J, Zhang YW, Zhang N, Li Z, Chang N, Hu X. Enhancing adsorption capacity while maintaining specific recognition performance of mesoporous silica: a novel imprinting strategy with amphiphilic ionic liquid as surfactant. NANOTECHNOLOGY 2018; 29:375604. [PMID: 29926809 DOI: 10.1088/1361-6528/aace10] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
In order to facilitate the broad applications of molecular recognition materials in biomedical areas, it is critical to enhance their adsorption capacity while maintaining their excellent recognition performance. In this work, we designed and synthesized well-defined peptide-imprinted mesoporous silica (PIMS) for specific recognition of an immunostimulating hexapeptide from human casein (IHHC) by using amphiphilic ionic liquid as the surfactant to anchor IHHC via a combination of one-step sol-gel method and docking oriented imprinting approach. Thereinto, theoretical calculation was employed to reveal the multiple binding interactions and dual-template configuration between amphiphilic ionic liquid and IHHC. The fabricated PIMS was characterized and an in-depth analysis of specific recognition mechanism was conducted. Results revealed that both adsorption and recognition capabilities of PIMS far exceeded that of the NIMS's. More significantly, the PIMS exhibited a superior binding capacity (60.5 mg g-1), which could increase 18.9% than the previous work. The corresponding imprinting factor and selectivity coefficient could reach up to 4.51 and 3.30, respectively. The PIMS also possessed lickety-split kinetic binding for IHHC, where the equilibrium time was only 10 min. All of these merits were due to the high surface area and the synergistic effect of multiple interactions (including hydrogen bonding, π-π stacking, ion-ion electrostatic interactions and van der Waals interactions, etc) between PIMS and IHHC in imprinted sites. The present work suggests the potential application of PIMS for large-scale and high-effective separation of IHHC, which may lead to their broad applications in drug/gene deliver, biosensors, catalyst and so on.
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Affiliation(s)
- Shichao Ding
- Department of Applied Chemistry, Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education, School of Nature and Applied Science, Northwestern Polytechnical University, Xi'an 710072, People's Republic of China
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27
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Patel AN, Kranz C. (Multi)functional Atomic Force Microscopy Imaging. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2018; 11:329-350. [PMID: 29490193 DOI: 10.1146/annurev-anchem-061417-125716] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Incorporating functionality to atomic force microscopy (AFM) to obtain physical and chemical information has always been a strong focus in AFM research. Modifying AFM probes with specific molecules permits accessibility of chemical information via specific reactions and interactions. Fundamental understanding of molecular processes at the solid/liquid interface with high spatial resolution is essential to many emerging research areas. Nanoscale electrochemical imaging has emerged as a complementary technique to advanced AFM techniques, providing information on electrochemical interfacial processes. While this review presents a brief introduction to advanced AFM imaging modes, such as multiparametric AFM and topography recognition imaging, the main focus herein is on electrochemical imaging via hybrid AFM-scanning electrochemical microscopy. Recent applications and the challenges associated with such nanoelectrochemical imaging strategies are presented.
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Affiliation(s)
- Anisha N Patel
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Ulm 89081, Germany;
| | - Christine Kranz
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Ulm 89081, Germany;
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28
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Panda K, Hyeok JJ, Park JY, Sankaran KJ, Balakrishnan S, Lin IN. Nanoscale investigation of enhanced electron field emission for silver ion implanted/post-annealed ultrananocrystalline diamond films. Sci Rep 2017; 7:16325. [PMID: 29176566 PMCID: PMC5701233 DOI: 10.1038/s41598-017-16395-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 11/13/2017] [Indexed: 11/09/2022] Open
Abstract
Silver (Ag) ions are implanted in ultrananocrystalline diamond (UNCD) films to enhance the electron field emission (EFE) properties, resulting in low turn-on field of 8.5 V/μm with high EFE current density of 6.2 mA/cm2 (at an applied field of 20.5 V/μm). Detailed nanoscale investigation by atomic force microscopy based peak force-controlled tunneling atomic force microscopy (PF-TUNA) and ultra-high vacuum scanning tunneling microscopy (STM) based current imaging tunneling spectroscopy (CITS) reveal that the UNCD grain boundaries are the preferred electron emission sites. The two scanning probe microscopic results supplement each other well. However, the PF-TUNA measurement is found to be better for explaining the local electron emission behavior than the STM-based CITS technique. The formation of Ag nanoparticles induced abundant sp2 nanographitic phases along the grain boundaries facilitate the easy transport of electrons and is believed to be a prime factor in enhancing the conductivity/EFE properties of UNCD films. The nanoscale understanding on the origin of electron emission sites in Ag-ion implanted/annealed UNCD films using the scanning probe microscopic techniques will certainly help in developing high-brightness electron sources for flat-panel displays applications.
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Affiliation(s)
- Kalpataru Panda
- Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 34141, Korea.
| | - Jeong Jin Hyeok
- Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea
| | - Jeong Young Park
- Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 34141, Korea. .,Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea.
| | | | - Sundaravel Balakrishnan
- Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603 102, India
| | - I-Nan Lin
- Department of Physics, Tamkang University, Tamsui, 251, Taiwan, ROC
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29
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Deng J, Nellist MR, Stevens MB, Dette C, Wang Y, Boettcher SW. Morphology Dynamics of Single-Layered Ni(OH) 2/NiOOH Nanosheets and Subsequent Fe Incorporation Studied by in Situ Electrochemical Atomic Force Microscopy. NANO LETTERS 2017; 17:6922-6926. [PMID: 28991484 DOI: 10.1021/acs.nanolett.7b03313] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Nickel (oxy)hydroxide-based (NiOxHy) materials are widely used for energy storage and conversion devices. Understanding dynamic processes at the solid-liquid interface of nickel (oxy)hydroxide is important to improve reaction kinetics and efficiencies. In this study, in situ electrochemical atomic force microscopy (EC-AFM) was used to directly investigate dynamic changes of single-layered Ni(OH)2 nanosheets during electrochemistry measurements. Reconstruction of Ni(OH)2 nanosheets, along with insertion of ions from the electrolyte, results in an increase of the volume by 56% and redox capacity by 300%. We also directly observe Fe cations adsorb and integrate heterogeneously into or onto the nanosheets as a function of applied potential, further increasing apparent volume. Our findings are important for the fundamental understanding of NiOxHy-based supercapacitors and oxygen-evolution catalysts, illustrating the dynamic nature of Ni-based nanostructures under electrochemical conditions.
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Affiliation(s)
- Jiang Deng
- Advanced Materials and Catalysis Group, Center for Chemistry of High-performance and Novel Materials, Department of Chemistry, Zhejiang University , Hangzhou 310028, P. R. China
| | - Michael R Nellist
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States
| | - Michaela Burke Stevens
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States
| | - Christian Dette
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States
| | - Yong Wang
- Advanced Materials and Catalysis Group, Center for Chemistry of High-performance and Novel Materials, Department of Chemistry, Zhejiang University , Hangzhou 310028, P. R. China
| | - Shannon W Boettcher
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States
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30
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Qiu J, Hajibabaei H, Nellist MR, Laskowski FAL, Hamann TW, Boettcher SW. Direct in Situ Measurement of Charge Transfer Processes During Photoelectrochemical Water Oxidation on Catalyzed Hematite. ACS CENTRAL SCIENCE 2017; 3:1015-1025. [PMID: 28979943 PMCID: PMC5620968 DOI: 10.1021/acscentsci.7b00310] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Indexed: 05/28/2023]
Abstract
Electrocatalysts improve the efficiency of light-absorbing semiconductor photoanodes driving the oxygen evolution reaction, but the precise function(s) of the electrocatalysts remains unclear. We directly measure, for the first time, the interface carrier transport properties of a prototypical visible-light-absorbing semiconductor, α-Fe2O3, in contact with one of the fastest known water oxidation catalysts, Ni0.8Fe0.2O x , by directly measuring/controlling the current and/or voltage at the Ni0.8Fe0.2O x catalyst layer using a second working electrode. The measurements demonstrate that the majority of photogenerated holes in α-Fe2O3 directly transfer to the catalyst film over a wide range of conditions and that the Ni0.8Fe0.2O x is oxidized by photoholes to an operating potential sufficient to drive water oxidation at rates that match the photocurrent generated by the α-Fe2O3. The Ni0.8Fe0.2O x therefore acts as both a hole-collecting contact and a catalyst for the photoelectrochemical water oxidation process. Separate measurements show that the illuminated junction photovoltage across the α-Fe2O3|Ni0.8Fe0.2O x interface is significantly decreased by the oxidation of Ni2+ to Ni3+ and the associated increase in the Ni0.8Fe0.2O x electrical conductivity. In sum, the results illustrate the underlying operative charge-transfer and photovoltage generation mechanisms of catalyzed photoelectrodes, thus guiding their continued improvement.
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Affiliation(s)
- Jingjing Qiu
- Department
of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Hamed Hajibabaei
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Michael R. Nellist
- Department
of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Forrest A. L. Laskowski
- Department
of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Thomas W. Hamann
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Shannon W. Boettcher
- Department
of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
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31
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Zhu C, Soldatov A, Mathew AP. Advanced microscopy and spectroscopy reveal the adsorption and clustering of Cu(ii) onto TEMPO-oxidized cellulose nanofibers. NANOSCALE 2017; 9:7419-7428. [PMID: 28530277 DOI: 10.1039/c7nr01566f] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
TEMPO (2,2,6,6-tetramethylpiperidine-1-oxylradical)-mediated oxidation nanofibers (TOCNF), as a biocompatible and bioactive material, have opened up a new application of nanocellulose for the removal of water contaminants. This development demands extremely sensitive and accurate methods to understand the surface interactions between water pollutants and TOCNF. In this report, we investigated the adsorption of metal ions on TOCNF surfaces using experimental techniques atthe nano and molecular scales with Cu(ii) as the target pollutant in both aqueous and dry forms. Imaging with in situ atomic force microscopy (AFM), together with a study of the physiochemical properties of TOCNF caused by adsorption with Cu(ii) in liquid, were conducted using the PeakForce Quantitative NanoMechanics (PF-QNM) mode at the nano scale. The average adhesion force between the tip and the target single TOCNF almost tripled after adsorption with Cu(ii) from 50 pN to 140 pN. The stiffness of the TOCNF was also enhanced because the Cu(ii) bound to the carboxylate groups and hardened the fiber. AFM topography, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) mapping and X-ray photoelectron spectroscopy (XPS) indicated that the TOCNF were covered by copper nanolayers and/or nanoparticles after adsorption. The changes in the molecular structure caused by the adsorption were demonstrated by Raman and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). This methodology will be of great assistance to gain qualitative and quantitative information on the adsorption process and interaction between charged entities in aqueous medium.
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Affiliation(s)
- Chuantao Zhu
- Department of Materials and Environmental Chemistry, Stockholm University, 10691, Stockholm, Sweden.
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32
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Page A, Perry D, Unwin PR. Multifunctional scanning ion conductance microscopy. Proc Math Phys Eng Sci 2017; 473:20160889. [PMID: 28484332 PMCID: PMC5415692 DOI: 10.1098/rspa.2016.0889] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/13/2017] [Indexed: 12/21/2022] Open
Abstract
Scanning ion conductance microscopy (SICM) is a nanopipette-based technique that has traditionally been used to image topography or to deliver species to an interface, particularly in a biological setting. This article highlights the recent blossoming of SICM into a technique with a much greater diversity of applications and capability that can be used either standalone, with advanced control (potential-time) functions, or in tandem with other methods. SICM can be used to elucidate functional information about interfaces, such as surface charge density or electrochemical activity (ion fluxes). Using a multi-barrel probe format, SICM-related techniques can be employed to deposit nanoscale three-dimensional structures and further functionality is realized when SICM is combined with scanning electrochemical microscopy (SECM), with simultaneous measurements from a single probe opening up considerable prospects for multifunctional imaging. SICM studies are greatly enhanced by finite-element method modelling for quantitative treatment of issues such as resolution, surface charge and (tip) geometry effects. SICM is particularly applicable to the study of living systems, notably single cells, although applications extend to materials characterization and to new methods of printing and nanofabrication. A more thorough understanding of the electrochemical principles and properties of SICM provides a foundation for significant applications of SICM in electrochemistry and interfacial science.
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Affiliation(s)
- Ashley Page
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
- MOAC Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, UK
| | - David Perry
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
- MOAC Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, UK
| | - Patrick R. Unwin
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
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