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What is the primary focus of the course Functional Materials I?
What is the primary focus of the course Functional Materials I?
What kind of materials will be primarily discussed in the section on electroceramics?
What kind of materials will be primarily discussed in the section on electroceramics?
Which of the following devices is included in the Functional Materials course content?
Which of the following devices is included in the Functional Materials course content?
What is the recommended method to ask questions during lectures?
What is the recommended method to ask questions during lectures?
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What is a potential topic in the lecture series on Energy Materials?
What is a potential topic in the lecture series on Energy Materials?
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What type of exam is mentioned for the course Functional Materials?
What type of exam is mentioned for the course Functional Materials?
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Which topic is NOT mentioned as part of the Functional Materials lecture series?
Which topic is NOT mentioned as part of the Functional Materials lecture series?
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Where will the lectures for Functional Materials I take place?
Where will the lectures for Functional Materials I take place?
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What physical effect is associated with NTC thermistors?
What physical effect is associated with NTC thermistors?
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Which type of thermistor is primarily used for overcurrent protection?
Which type of thermistor is primarily used for overcurrent protection?
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What phenomenon does the varistor utilize for overvoltage protection?
What phenomenon does the varistor utilize for overvoltage protection?
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Which of these materials exhibits a metallic to semiconducting phase transition?
Which of these materials exhibits a metallic to semiconducting phase transition?
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What is a key characteristic of ZnO used in varistors?
What is a key characteristic of ZnO used in varistors?
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In which of the following applications would you likely find RuO2/glass composites?
In which of the following applications would you likely find RuO2/glass composites?
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What type of resistor is classified as a voltage dependent resistor?
What type of resistor is classified as a voltage dependent resistor?
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Which of the following is least likely to be associated with electroceramics?
Which of the following is least likely to be associated with electroceramics?
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What kind of structure do ferroelectrics have that leads to spontaneous electric polarization?
What kind of structure do ferroelectrics have that leads to spontaneous electric polarization?
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Which phase of BaTiO3 is paraelectric and has an inversion center?
Which phase of BaTiO3 is paraelectric and has an inversion center?
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What causes the tetragonal distorted phase of BaTiO3 to lose its inversion center?
What causes the tetragonal distorted phase of BaTiO3 to lose its inversion center?
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Which material is an important example of a ferroelectric used in various applications?
Which material is an important example of a ferroelectric used in various applications?
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What property of BaTiO3 is leveraged around its ferroelectric-paraelectric phase transition?
What property of BaTiO3 is leveraged around its ferroelectric-paraelectric phase transition?
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What phenomenon occurs in semiconductors like BaTiO3 when exposed to voltage limits?
What phenomenon occurs in semiconductors like BaTiO3 when exposed to voltage limits?
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Which group of materials includes ZnO and is used as varistors for overvoltage protection?
Which group of materials includes ZnO and is used as varistors for overvoltage protection?
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In the context of electroceramics, varistors serve to protect against which of the following?
In the context of electroceramics, varistors serve to protect against which of the following?
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What is a primary application of dielectric ceramics?
What is a primary application of dielectric ceramics?
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Which effect in piezoelectric ceramics generates mechanical stress leading to polarization?
Which effect in piezoelectric ceramics generates mechanical stress leading to polarization?
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Which of the following materials is an important example of pyroelectric ceramics?
Which of the following materials is an important example of pyroelectric ceramics?
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In the context of ion-conducting ceramics, what role does Y3+ play in Y2O3-doped ZrO2?
In the context of ion-conducting ceramics, what role does Y3+ play in Y2O3-doped ZrO2?
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What is a key application of the inverse piezoelectric effect?
What is a key application of the inverse piezoelectric effect?
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Which of the following describes the primary function of pyroelectric ceramics in fire alarm systems?
Which of the following describes the primary function of pyroelectric ceramics in fire alarm systems?
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What type of structure does lead-zirconate-titanate (PZT) crystallize in?
What type of structure does lead-zirconate-titanate (PZT) crystallize in?
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What application is facilitated by the use of Li-ion conductors in ceramics?
What application is facilitated by the use of Li-ion conductors in ceramics?
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What is the primary component of most ceramic materials?
What is the primary component of most ceramic materials?
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Which of the following structures does a ceramic material typically create?
Which of the following structures does a ceramic material typically create?
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In ionic compounds, where do cations typically occupy in a crystal structure?
In ionic compounds, where do cations typically occupy in a crystal structure?
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What is the coordination number dependent on in ionic compounds?
What is the coordination number dependent on in ionic compounds?
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What is the crystal structure of NaCl classified as?
What is the crystal structure of NaCl classified as?
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Which ions occupy tetrahedral interstitial sites in the fluorite structure (CaF2)?
Which ions occupy tetrahedral interstitial sites in the fluorite structure (CaF2)?
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What is particularly noteworthy about the ionic radius of cations compared to anions in ceramic materials?
What is particularly noteworthy about the ionic radius of cations compared to anions in ceramic materials?
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What ensures the efficient packing of ions in crystal structures of ceramics?
What ensures the efficient packing of ions in crystal structures of ceramics?
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What does the coordination number for A cations in a perovskite structure indicate?
What does the coordination number for A cations in a perovskite structure indicate?
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What is the significance of the tolerance factor t in perovskite structures?
What is the significance of the tolerance factor t in perovskite structures?
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What structure do the O2- anions occupy in the perovskite structure CaTiO3?
What structure do the O2- anions occupy in the perovskite structure CaTiO3?
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Which of the following best describes the distortion in perovskite structures?
Which of the following best describes the distortion in perovskite structures?
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At what critical temperature does BaTiO3 display an ideal cubic perovskite structure?
At what critical temperature does BaTiO3 display an ideal cubic perovskite structure?
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What type of structure does CaTiO3 form due to the difference in cation sizes?
What type of structure does CaTiO3 form due to the difference in cation sizes?
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In the context of perovskite structures, when does spontaneous electric polarization occur?
In the context of perovskite structures, when does spontaneous electric polarization occur?
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Which cation carries a higher charge in a distorted perovskite structure?
Which cation carries a higher charge in a distorted perovskite structure?
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What is the primary characteristic of the rutile structure?
What is the primary characteristic of the rutile structure?
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Which of the following shapes is associated with the coordination number of 12 in the perovskite structure?
Which of the following shapes is associated with the coordination number of 12 in the perovskite structure?
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Study Notes
Functional Materials Overview
- Course name: Functional Materials – PHT.708UF (Masters Program Technical Physics) and Functional Materials I - MAS.220UF (Masters Program Advanced Materials Science)
- Instructor: Dr. Stefan Topolovec
- Institute: Institute of Materials Physics
- Date: 07.10.2024
Course Structure and Organisation
- Lecture Dates: Mondays, 11:15-12:45, TDK Seminarraum. Exception: Different room (HS 3.1, Petersgasse 10-12) on 16.12
- TeachCenter Resources: Lecture slides available online before each session; links to references for further studies
- Oral Exam: Appointment dates announced at the end of the semester via TeachCenter; individual appointments can be arranged by contacting the instructor via email.
- Consultation: Contact Dr. Stefan Topolovec ([email protected]) for consultation hours or questions.
- Interactive Learning: Opportunities to ask questions during lectures encouraged
Lecture Overview
- 1. Electroceramics: An introduction to electroceramics, with an overview of their properties and applications. Covers atomic structures, electronic properties and devices.
- 2. Energy Materials: A brief overview of electrochemical principles, including Li-ion batteries and subsequent battery technologies.
- 3. Superconducting Materials: Introduction to superconductivity, covering Type-II superconductors and high-temperature superconductors.
- 4. Other Functional Materials: This section covers redox-flow batteries, electrochemical capacitors/supercapacitors, fuel cells, oxygen sensors and hydrogen storage.
Specific Topics (1. Electroceramics)
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Resistors: Linear and Non-linear resistors based on electroceramics. Focus on oxide ceramics' wide conductivity range and how non-linear materials (varistors and thermistors) change resistance with voltage or temperature. Includes specific types like NTC (negative temperature coefficient) and PTC (positive temperature coefficient) thermistors and their material examples (e.g., Spinels, (Ni,Mn)₃O₄ ). Details of physical effects of these materials (like hopping conduction or grain boundary phenomena) are included, along with application examples like overcurrent protection.
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Dielectric Ceramics: High-specific-resistance ceramic materials with applications in insulators, ceramic capacitors, and microwave components (resonators, filters, antennas). Examples of materials used include Al₂O₃, Si₃N₄, BaTiO₃, Ba(Zn, Ta)O₃.
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Piezoelectric Ceramics: Materials that couple mechanical and electrical properties. Details of direct and inverse piezoelectric effects included, along with applications in actuators (positioning, switching) and sensors (acceleration, microphones). Lead-zirconate-titanate (PZT) is highlighted as an important example.
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Pyroelectric Ceramics: Materials where the temperature dependence of spontaneous polarization causes charge flow. Applications include infrared detectors for fire alarm and thermal imaging systems. PbTiO₃ is provided as a key example.
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Ion-conducting Ceramics: Materials used as solid electrolytes that enable fast ion diffusion. Focus on oxygen-ion conductors, specifically Y₂O₃-doped ZrO₂, highlighting its application in high-temperature fuel cells.
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1.2 Atomic structure of ceramic materials: Crystal structures along with point defects of ceramics are discussed. Examples shown include NaCl, fluorite, and rutile.
Learning Objectives
Students will understand the physical principles of functional materials and their practical applications in electrical engineering, electronics, and energy storage.
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Description
Test your knowledge on the key concepts and topics covered in the Functional Materials I course. This quiz explores the various types of materials, devices, and applications discussed, particularly focusing on electroceramics and energy materials. Challenge yourself with questions related to specific properties and characteristics of functional materials.
