Other affiliations: Chalmers University of Technology, Texas A&M University
Bio: Claes-Göran Granqvist is an academic researcher from Uppsala University. The author has contributed to research in topic(s): Electrochromism & Thin film. The author has an hindex of 73, co-authored 535 publication(s) receiving 31523 citation(s). Previous affiliations of Claes-Göran Granqvist include Chalmers University of Technology & Texas A&M University.
Papers published on a yearly basis
01 Dec 1986-Journal of Applied Physics
TL;DR: In this paper, the authors reviewed work on In2O3:Sn films prepared by reactive e−beam evaporation of In2 O3 with up to 9 mol'% SnO2 onto heated glass.
Abstract: We review work on In2O3:Sn films prepared by reactive e‐beam evaporation of In2O3 with up to 9 mol % SnO2 onto heated glass. These films have excellent spectrally selective properties when the deposition rate is ∼0.2 nm/s, the substrate temperature is ≳150 °C, and the oxygen pressure is ∼5×10−4 Torr. Optimized coatings have crystallite dimensions ≳50 nm and a C‐type rare‐earth oxide structure. We cover electromagnetic properties as recorded by spectrophotometry in the 0.2–50‐μm range, by X‐band microwave reflectance, and by dc electrical measurements. Hall‐effect data are included. An increase of the Sn content is shown to have several important effects: the semiconductor band gap is shifted towards the ultraviolet, the luminous transmittance remains high, the infrared reflectance increases to a high value beyond a certain wavelength which shifts towards the visible, phonon‐induced infrared absorption bands vanish, the microwave reflectance goes up, and the dc resisitivity drops to ∼2×10−4 Ω cm. The corre...
01 Jan 1995
TL;DR: In this paper, a case study on tungsten oxide is presented, where the authors discuss the preparation, structure, and composition of sputter-deposited tungstern oxide films.
Abstract: Part 1 Case study on tungsten oxide: bulk crystalline tungsten oxide tungsten oxide films - preparation, structure, and composition of evaporated films tungsten oxide films - preparation, structure, and composition of sputter-deposited films tungsten oxide films - preparation, structure, and composition of electrochemically and chemically prepared films tungsten oxide films - ion intercalation/deintercalation studied by electrochemical techniques tungsten oxide films - ion intercalation/deintercalation studied by physical techniques tungsten oxide films -ultraviolet absorption and semiconductor bandgap tungsten oxide films - optical properties in the luminous and near-infrared range tungsten oxide films - theoretical models for the optical properties tungsten oxide films - electrical properties. Part 2 Electrochromism among the oxides (except tungsten oxide): molybdenum oxide films miscellaneous tungsten- and molybdenum-oxide-containing films iridium oxide films titanium oxide films manganese oxide films vanadium dioxide films vanadium pentoxide films nickel oxide films cobalt oxide films niobium oxide films miscellaneous oxide films systematics for the electrochromism in transition metal oxides inorganic non-oxide electrochromic materials. Part 3 Electrochromic devices: transparent electrical conductors electrolytes and ion conductors ion storage materials - brief overview devices with liquid electrolytes devices with solid inorganic electrolytes and ion conductors devices with polymer electrolytes time-dependent device performance - a unified treatment.
01 May 1976-Journal of Applied Physics
TL;DR: In this paper, a statistical growth model based on the Central Limit Theorem has been formulated for liquid-like coalescence of particles; this theory accounts satisfactorily for all the data, as well as for most size distributions published in the literature.
Abstract: In this paper we present a novel and versatile t e c h n i q u e f o r t h e p r o d u c t i o n o f u l t r a f i n e m e t a l p a r t i c l e s by evaporation from a temperature‐regulated oven containing a reduced atmosphere of an inert gas. An extensive investigation of particles of oxidized Al, with diameters of 3 to 6 nm, has been performed. We have also studied ultrafine particles of Mg,Zn, and Sn produced in the same manner. A supplementing investigation has been carried out for particles of Cr, Fe, Co, Ni, Cu, and Ga, as well as larger Al particles, produced by ’’conventional’’ inert‐gas evaporation from a resistive filament. Diameter as a function of evaporation rate, inert‐gas pressure, and the kind of inert gas are reported. Crystalline particles smaller than 20 nm look almost spherical in the electron microscope, while larger ones often display pronounced crystal habit. S i z e d i s t r i b u t i o n s have been investigated in detail, and consistently the logarithm of the particle diameter has a Gaussian distribution to a high precision for the smallest sizes, whereas larger particles deviate from such a simple behavior. A statistical growth model, based on the Central Limit Theorem, has been formulated for liquidlike coalescence of particles; this theory accounts satisfactorily for all our data, as well as for most size distributions published in the literature. Applications of the model to colloids, discontinuous films, and supported catalysts are discussed. By comparing size distributions for particles produced by a variety of techniques we found a number of empirical rules for the width of the distributions, as defined by a (geometric) standard deviation σ. For crystalline inert‐gas‐ evaporated particles we obtained consistently 1.36?σ?1.60; for coalescing islands in discontinuous films we found 1.22?σ?1.34; and similar rules are applicable to colloids, supported catalysts, and to ultrafine droplets.
TL;DR: Transparent conductors (TCs) have a multitude of applications for solar energy utilization and for energy savings, especially in buildings as discussed by the authors, which leads naturally to considerations of spectral selectivity, angular selectivity, and temporal variability of TCs, as covered in three subsequent sections.
Abstract: Transparent conductors (TCs) have a multitude of applications for solar energy utilization and for energy savings, especially in buildings. The largest of these applications, in terms of area, make use of the fact that the TCs have low infrared emittance and hence can be used to improve the thermal properties of modern fenestration. Depending on whether the TCs are reflecting or not in the near infrared pertinent to solar irradiation, the TCs can serve in “solar control” or “low-emittance” windows. Other applications rely on the electrical conductivity of the TCs, which make them useful as current collectors in solar cells and for inserting and extracting electrical charge in electrochromic “smart windows” capable of combining energy efficiency and indoor comfort in buildings. This Review takes a “panoramic” view on TCs and discusses their properties from the perspective of the radiative properties in our ambience. This approach leads naturally to considerations of spectral selectivity , angular selectivity , and temporal variability of TCs, as covered in three subsequent sections. The spectrally selective materials are thin films based on metals (normally gold or titanium nitride) or wide band gap semiconductors with heavy doping (normally based on indium, tin, or zinc). Their applications to energy-efficient windows are covered in detail, experimentally as well as theoretically, and briefer discussions are given applications to solar cells and solar collectors. Photocatalytic properties and super-hydrophilicity are touched upon. Angular selective TCs, for which the angular properties are caused by inclined columnar nanostructures, are then covered. A discussion of TC-like materials with thermochromic and electrochromic properties follows in the final part. Detailed treatments are given for thermochromic materials based on vanadium dioxide and for electrochromic multi-layer structures (incorporating TCs as essential components). The reference list is extensive and aims at giving an easy entrance to the many varied aspects of TCs.
TL;DR: In this article, the progress that has taken place since 1993 with regard to film deposition, characterization by physical and chemical techniques, optical properties, as well as electrochromic device assembly and performance is reviewed.
Abstract: W oxide films are of critical importance for electrochromic device technology, such as for smart windows capable of varying the throughput of visible light and solar energy. This paper reviews the progress that has taken place since 1993 with regard to film deposition, characterization by physical and chemical techniques, optical properties, as well as electrochromic device assembly and performance. The main goal is to provide an easy entrance to the relevant scientific literature.
01 Jan 2015
23 Jun 2007-Chemical Reviews
01 Sep 2010-Nature Photonics
TL;DR: Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability as discussed by the authors, and its true potential lies in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultrawideband tunability.
Abstract: The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential lies in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultrawideband tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light-emitting devices to touch screens, photodetectors and ultrafast lasers. Here we review the state-of-the-art in this emerging field.
04 Apr 2005
Abstract: Preface. Preface to the First Edition. Contributors. Contributors to the First Edition. Chapter 1. Fundamentals of Impedance Spectroscopy (J.Ross Macdonald and William B. Johnson). 1.1. Background, Basic Definitions, and History. 1.1.1 The Importance of Interfaces. 1.1.2 The Basic Impedance Spectroscopy Experiment. 1.1.3 Response to a Small-Signal Stimulus in the Frequency Domain. 1.1.4 Impedance-Related Functions. 1.1.5 Early History. 1.2. Advantages and Limitations. 1.2.1 Differences Between Solid State and Aqueous Electrochemistry. 1.3. Elementary Analysis of Impedance Spectra. 1.3.1 Physical Models for Equivalent Circuit Elements. 1.3.2 Simple RC Circuits. 1.3.3 Analysis of Single Impedance Arcs. 1.4. Selected Applications of IS. Chapter 2. Theory (Ian D. Raistrick, Donald R. Franceschetti, and J. Ross Macdonald). 2.1. The Electrical Analogs of Physical and Chemical Processes. 2.1.1 Introduction. 2.1.2 The Electrical Properties of Bulk Homogeneous Phases. 220.127.116.11 Introduction. 18.104.22.168 Dielectric Relaxation in Materials with a Single Time Constant. 22.214.171.124 Distributions of Relaxation Times. 126.96.36.199 Conductivity and Diffusion in Electrolytes. 188.8.131.52 Conductivity and Diffusion-a Statistical Description. 184.108.40.206 Migration in the Absence of Concentration Gradients. 220.127.116.11 Transport in Disordered Media. 2.1.3 Mass and Charge Transport in the Presence of Concentration Gradients. 18.104.22.168 Diffusion. 22.214.171.124 Mixed Electronic-Ionic Conductors. 126.96.36.199 Concentration Polarization. 2.1.4 Interfaces and Boundary Conditions. 188.8.131.52 Reversible and Irreversible Interfaces. 184.108.40.206 Polarizable Electrodes. 220.127.116.11 Adsorption at the Electrode-Electrolyte Interface. 18.104.22.168 Charge Transfer at the Electrode-Electrolyte Interface. 2.1.5 Grain Boundary Effects. 2.1.6 Current Distribution, Porous and Rough Electrodes- the Effect of Geometry. 22.214.171.124 Current Distribution Problems. 126.96.36.199 Rough and Porous Electrodes. 2.2. Physical and Electrochemical Models. 2.2.1 The Modeling of Electrochemical Systems. 2.2.2 Equivalent Circuits. 188.8.131.52 Unification of Immitance Responses. 184.108.40.206 Distributed Circuit Elements. 220.127.116.11 Ambiguous Circuits. 2.2.3 Modeling Results. 18.104.22.168 Introduction. 22.214.171.124 Supported Situations. 126.96.36.199 Unsupported Situations: Theoretical Models. 188.8.131.52 Unsupported Situations: Equivalent Network Models. 184.108.40.206 Unsupported Situations: Empirical and Semiempirical Models. Chapter 3. Measuring Techniques and Data Analysis. 3.1. Impedance Measurement Techniques (Michael C. H. McKubre and Digby D. Macdonald). 3.1.1 Introduction. 3.1.2 Frequency Domain Methods. 220.127.116.11 Audio Frequency Bridges. 18.104.22.168 Transformer Ratio Arm Bridges. 22.214.171.124 Berberian-Cole Bridge. 126.96.36.199 Considerations of Potentiostatic Control. 188.8.131.52 Oscilloscopic Methods for Direct Measurement. 184.108.40.206 Phase-Sensitive Detection for Direct Measurement. 220.127.116.11 Automated Frequency Response Analysis. 18.104.22.168 Automated Impedance Analyzers. 22.214.171.124 The Use of Kramers-Kronig Transforms. 126.96.36.199 Spectrum Analyzers. 3.1.3 Time Domain Methods. 188.8.131.52 Introduction. 184.108.40.206 Analog-to-Digital (A/D) Conversion. 220.127.116.11 Computer Interfacing. 18.104.22.168 Digital Signal Processing. 3.1.4 Conclusions. 3.2. Commercially Available Impedance Measurement Systems (Brian Sayers). 3.2.1 Electrochemical Impedance Measurement Systems. 22.214.171.124 System Configuration. 126.96.36.199 Why Use a Potentiostat? 188.8.131.52 Measurements Using 2, 3 or 4-Terminal Techniques. 184.108.40.206 Measurement Resolution and Accuracy. 220.127.116.11 Single Sine and FFT Measurement Techniques. 18.104.22.168 Multielectrode Techniques. 22.214.171.124 Effects of Connections and Input Impedance. 126.96.36.199 Verification of Measurement Performance. 188.8.131.52 Floating Measurement Techniques. 184.108.40.206 Multichannel Techniques. 3.2.2 Materials Impedance Measurement Systems. 220.127.116.11 System Configuration. 18.104.22.168 Measurement of Low Impedance Materials. 22.214.171.124 Measurement of High Impedance Materials. 126.96.36.199 Reference Techniques. 188.8.131.52 Normalization Techniques. 184.108.40.206 High Voltage Measurement Techniques. 220.127.116.11 Temperature Control. 18.104.22.168 Sample Holder Considerations. 3.3. Data Analysis (J. Ross Macdonald). 3.3.1 Data Presentation and Adjustment. 22.214.171.124 Previous Approaches. 126.96.36.199 Three-Dimensional Perspective Plotting. 188.8.131.52 Treatment of Anomalies. 3.3.2 Data Analysis Methods. 184.108.40.206 Simple Methods. 220.127.116.11 Complex Nonlinear Least Squares. 18.104.22.168 Weighting. 22.214.171.124 Which Impedance-Related Function to Fit? 126.96.36.199 The Question of "What to Fit" Revisited. 188.8.131.52 Deconvolution Approaches. 184.108.40.206 Examples of CNLS Fitting. 220.127.116.11 Summary and Simple Characterization Example. Chapter 4. Applications of Impedance Spectroscopy. 4.1. Characterization of Materials (N. Bonanos, B. C. H. Steele, and E. P. Butler). 4.1.1 Microstructural Models for Impedance Spectra of Materials. 18.104.22.168 Introduction. 22.214.171.124 Layer Models. 126.96.36.199 Effective Medium Models. 188.8.131.52 Modeling of Composite Electrodes. 4.1.2 Experimental Techniques. 184.108.40.206 Introduction. 220.127.116.11 Measurement Systems. 18.104.22.168 Sample Preparation-Electrodes. 22.214.171.124 Problems Associated With the Measurement of Electrode Properties. 4.1.3 Interpretation of the Impedance Spectra of Ionic Conductors and Interfaces. 126.96.36.199 Introduction. 188.8.131.52 Characterization of Grain Boundaries by IS. 184.108.40.206 Characterization of Two-Phase Dispersions by IS. 220.127.116.11 Impedance Spectra of Unusual Two-phase Systems. 18.104.22.168 Impedance Spectra of Composite Electrodes. 22.214.171.124 Closing Remarks. 4.2. Characterization of the Electrical Response of High Resistivity Ionic and Dielectric Solid Materials by Immittance Spectroscopy (J. Ross Macdonald). 4.2.1 Introduction. 4.2.2 Types of Dispersive Response Models: Strengths and Weaknesses. 126.96.36.199 Overview. 188.8.131.52 Variable-slope Models. 184.108.40.206 Composite Models. 4.2.3 Illustration of Typical Data Fitting Results for an Ionic Conductor. 4.3. Solid State Devices (William B. Johnson and Wayne L. Worrell). 4.3.1 Electrolyte-Insulator-Semiconductor (EIS) Sensors. 4.3.2 Solid Electrolyte Chemical Sensors. 4.3.3 Photoelectrochemical Solar Cells. 4.3.4 Impedance Response of Electrochromic Materials and Devices (Gunnar A. Niklasson, Anna Karin Johsson, and Maria Stromme). 220.127.116.11 Introduction. 18.104.22.168 Materials. 22.214.171.124 Experimental Techniques. 126.96.36.199 Experimental Results on Single Materials. 188.8.131.52 Experimental Results on Electrochromic Devices. 184.108.40.206 Conclusions and Outlook. 4.3.5 Time-Resolved Photocurrent Generation (Albert Goossens). 220.127.116.11 Introduction-Semiconductors. 18.104.22.168 Steady-State Photocurrents. 22.214.171.124 Time-of-Flight. 126.96.36.199 Intensity-Modulated Photocurrent Spectroscopy. 188.8.131.52 Final Remarks. 4.4. Corrosion of Materials (Digby D. Macdonald and Michael C. H. McKubre). 4.4.1 Introduction. 4.4.2 Fundamentals. 4.4.3 Measurement of Corrosion Rate. 4.4.4 Harmonic Analysis. 4.4.5 Kramer-Kronig Transforms. 4.4.6 Corrosion Mechanisms. 184.108.40.206 Active Dissolution. 220.127.116.11 Active-Passive Transition. 18.104.22.168 The Passive State. 4.4.7 Point Defect Model of the Passive State (Digby D. Macdonald). 22.214.171.124 Introduction. 126.96.36.199 Point Defect Model. 188.8.131.52 Electrochemical Impedance Spectroscopy. 184.108.40.206 Bilayer Passive Films. 4.4.8 Equivalent Circuit Analysis (Digby D. Macdonald and Michael C. H. McKubre). 220.127.116.11 Coatings. 4.4.9 Other Impedance Techniques. 18.104.22.168 Electrochemical Hydrodynamic Impedance (EHI). 22.214.171.124 Fracture Transfer Function (FTF). 126.96.36.199 Electrochemical Mechanical Impedance. 4.5. Electrochemical Power Sources. 4.5.1 Special Aspects of Impedance Modeling of Power Sources (Evgenij Barsoukov). 188.8.131.52 Intrinsic Relation Between Impedance Properties and Power Sources Performance. 184.108.40.206 Linear Time-Domain Modeling Based on Impedance Models, Laplace Transform. 220.127.116.11 Expressing Model Parameters in Electrical Terms, Limiting Resistances and Capacitances of Distributed Elements. 18.104.22.168 Discretization of Distributed Elements, Augmenting Equivalent Circuits. 22.214.171.124 Nonlinear Time-Domain Modeling of Power Sources Based on Impedance Models. 126.96.36.199 Special Kinds of Impedance Measurement Possible with Power Sources-Passive Load Excitation and Load Interrupt. 4.5.2 Batteries (Evgenij Barsoukov). 188.8.131.52 Generic Approach to Battery Impedance Modeling. 184.108.40.206 Lead Acid Batteries. 220.127.116.11 Nickel Cadmium Batteries. 18.104.22.168 Nickel Metal-hydride Batteries. 22.214.171.124 Li-ion Batteries. 4.5.3 Impedance Behavior of Electrochemical Supercapacitors and Porous Electrodes (Brian E. Conway). 126.96.36.199 Introduction. 188.8.131.52 The Time Factor in Capacitance Charge or Discharge. 184.108.40.206 Nyquist (or Argand) Complex-Plane Plots for Representation of Impedance Behavior. 220.127.116.11 Bode Plots of Impedance Parameters for Capacitors. 18.104.22.168 Hierarchy of Equivalent Circuits and Representation of Electrochemical Capacitor Behavior. 22.214.171.124 Impedance and Voltammetry Behavior of Brush Electrode Models of Porous Electrodes. 126.96.36.199 Impedance Behavior of Supercapacitors Based on Pseudocapacitance. 188.8.131.52 Deviations of Double-layer Capacitance from Ideal Behavior: Representation by a Constant-phase Element (CPE). 4.5.4 Fuel Cells (Norbert Wagner). 184.108.40.206 Introduction. 220.127.116.11 Alkaline Fuel Cells (AFC). 18.104.22.168 Polymer Electrolyte Fuel Cells (PEFC). 22.214.171.124 Solid Oxide Fuel Cells (SOFC). Appendix. Abbreviations and Definitions of Models. References. Index.