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Full-Text Articles in Engineering

Effects Of Polymer-Nanoparticle Interactions On The Dynamics Of Attractive Polyhedral Oligomeric Silsesquioxane Nanocomposites, Walter W. Young Mar 2024

Effects Of Polymer-Nanoparticle Interactions On The Dynamics Of Attractive Polyhedral Oligomeric Silsesquioxane Nanocomposites, Walter W. Young

Doctoral Dissertations

Polyhedral oligomeric silsesquioxane (POSS) had long been recognized as a critical building block for inorganic-organic hybrid materials with unique and desirable properties and performance. Through synthesis and characterization of polymer/POSS nanocomposites, direct insights into the significant effects of the polymer/POSS interactions on the resulting material properties are obtained. Random copolymers of a hydrogen-bond accepting monomer and a non-interacting monomer are synthesized and loaded with a model amine-functionalized hydrogen bond donating POSS molecule via solution casting, to create a material with well-controlled dynamical heterogeneity. The increase in the glass transition temperature (Tg) of these materials is found to strongly depend on …


Additive Manufacturing Of High-Performance Nanolamellar Eutectic High-Entropy Alloys, Jie Ren Aug 2023

Additive Manufacturing Of High-Performance Nanolamellar Eutectic High-Entropy Alloys, Jie Ren

Doctoral Dissertations

Additive manufacturing, also called three-dimensional (3D) printing, is an emerging technology for printing net-shaped components layer by layer for applications in automotive, aerospace, biomedical and other industries. In addition to the vast design freedom offered by this approach, metal 3D printing via laser powder-bed fusion (L-PBF) involves large temperature gradients and rapid cooling and provides exciting opportunities for producing microstructures and mechanical properties beyond those achievable by conventional processing routes. Although these extreme printing conditions enable microstructural refinement to the nanoscale for achieving high strength. However, high-strength nanostructured alloys by laser additive manufacturing often suffer from limited ductility. Eutectic high-entropy …


Polyesters Derived From Biobased 1,5-Pentanediol For Coatings, Adhesives, And Biodegradable Plastics, Lei Zheng Apr 2023

Polyesters Derived From Biobased 1,5-Pentanediol For Coatings, Adhesives, And Biodegradable Plastics, Lei Zheng

Doctoral Dissertations

Biomass-derived polymers are drawing increased attention from researchers due to unique performance attributes, potential for biodegradability, new low-cost feedstocks, and improved sustainability. Biobased feedstocks are employed in both major applications of polymers thermosets and thermoplastics. For thermoset coatings and adhesives, biobased resins such as biobased alkyds, epoxy resins, benzoxazine resins, starch derivatives, and proteins from plants and animals, are promising candidates to replace petroleum-derived counterparts. Thermoplastics such as polyethylene are mainly produced from fossil resources, generally have poor degradability and are difficult to effectively recycle. Currently, in the United States, less than 10% plastics are recycled, and more than 70% …


Polymer Based Energy Storage And Thermal Management On Textile Devices, Wesley A. Viola Apr 2023

Polymer Based Energy Storage And Thermal Management On Textile Devices, Wesley A. Viola

Doctoral Dissertations

Humans developed textiles to manage thermal energy transfer with the environment and support homeostasis in a wide range of climates. With the anticipation of wearable technologies to transform healthcare via early, pre-symptomatic detection of illness, there is now a demand for electrical energy storage to support such on-body devices. Finding energy materials to merge seamlessly with textiles is basic requirement to ensure widespread adoption of wearable health monitors. Here we use a vapor deposition process to conformally coat ordinary fabrics with the doped conjugated polymer poly(3,4 ethylenedioxythiophene) (PEDOT-Cl), a soft material which possesses electronic and redox capabilities. We demonstrate PEDOT-Cl …


Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil Apr 2023

Controlling Mechanical Properties Of Well-Defined Polymer Networks, Ipek Sacligil

Doctoral Dissertations

Polymer networks are one of the most versatile and highly studied material class that revolutionized many aspects of life. Connecting the final network properties to the molecular parameters of its building blocks remains a major research thrust. Recent advances in network synthesis techniques allowed for accurate predictions of elastic modulus in model networks. Tew Group has developed highly efficient, thiol-norbornene networks with controllable mechanical properties. Chapter 2 focuses on modifying the gel fracture energy predicted by Lake-Thomas theory by accounting for loop defects. This study allowed for a priori estimates of gel fracture energy by combining theory, experiments, and simulations. …


Bottom-Up Morphological Control Of Biphasic Polymer Particles Via Heterogeneous Polymerization, Heather S.C. Hamilton Apr 2023

Bottom-Up Morphological Control Of Biphasic Polymer Particles Via Heterogeneous Polymerization, Heather S.C. Hamilton

Doctoral Dissertations

Heterogeneous polymerization techniques are industrially relevant, scalable methods to synthesize polymer colloids and they have emerged in recent decades as viable methods to produce biphasic and morphologically complex polymer particles. The overarching goal of this thesis is to understand how heterogeneous polymerization techniques can be modified and optimized to control particle morphology through the systematic study of process parameters. Chapter 1 introduces relevant nomenclature and provides a brief historical perspective on the development of heterogeneous polymerization. This chapter also reviews the state-of-the-art techniques used to prepare morphologically complex polymer particles, with an emphasis on the heterogeneous polymerization processes studied in …


Effect Of Chemical Identity And Morphology On Amphiphilic-Zwitterionic Block Copolymer Membranes, Ria Ghosh Apr 2023

Effect Of Chemical Identity And Morphology On Amphiphilic-Zwitterionic Block Copolymer Membranes, Ria Ghosh

Doctoral Dissertations

Amphiphilic block copolymers have gained a broad research interest attributed to their self-assembly properties over a range of pH, temperature, and ionic strength. Polyzwitterions have attracted special attention due to their hydrophilicity, charge sensitivity and coulombic attraction of the opposite charges over a range of environments making them a popular material of study in the field of stimuli responsive systems, for example in self-healing hydrogels, and water transport membranes. Combining the stimuli responsiveness and higher hydrophilicity of zwitterionic polymers with self-assembly behavior of amphiphilic block copolymers created an interest to study the effect of composition and identity of the zwitterionic …


Structure-Function Relationships Of Bighorn Sheep Horncore Bone And Horn-Horncore Interface Materials For Energy Absorption Applications, Luca H. Fuller Apr 2023

Structure-Function Relationships Of Bighorn Sheep Horncore Bone And Horn-Horncore Interface Materials For Energy Absorption Applications, Luca H. Fuller

Doctoral Dissertations

Bighorn sheep rams do not show overt signs of traumatic brain injury from head impacts experienced during intraspecific combat. Rams’ cranial appendages bear the brunt of ramming impacts and are composed of a keratin-rich horn anchored to a bony horncore via a soft connective tissue interface. The horncore is filled with velar bone which has a unique porous architecture with a comparable bone volume fraction, but larger strut thickness and separation than typical mammalian trabecular bone. Velar bone absorbs more energy than the horn and substantially reduces post-impact brain cavity accelerations in computational models of bighorn sheep ramming. These findings …


Vapor Deposition Of Self-Wrinkling Polymer Films, Robert N. Enright Apr 2023

Vapor Deposition Of Self-Wrinkling Polymer Films, Robert N. Enright

Doctoral Dissertations

Initiated chemical vapor deposition is used to grow polymer films on substrates of various three-dimensional shapes which exhibit wrinkling during film growth, termed self-wrinkling. Self-wrinkling avoids separate film growth and compression steps and more-closely mimics processes observed in nature. The self-wrinkling process is elucidated on flat elastic substrates, revealing control over the amount of compressive stress by changing deposition conditions. Next, a study of films grown on liquid substrates with interface profiles that either resemble cylinders or contain repeating concave cones, saddles, and bowls affirms the principle that the wrinkle roundness increases with interface curvature. The selection of high versus …


Correlation Between Laboratory Testing Results And In-Situ Sidewalk Scaling, Brian R. Shea Apr 2023

Correlation Between Laboratory Testing Results And In-Situ Sidewalk Scaling, Brian R. Shea

Masters Theses

Scaling tests aim to induce scaling behavior in concrete specimens similar to environmental conditions. The efficacy of laboratory tests’ ability to match environmental conditions is important to be able to evaluate the durability of concrete exposed to freeze-thaw cycles and de-icers. This study attempts to correlate results between two existing scaling test standards, ASTM C672 and the BNQ NQ 2621-900. The correlation is done via scaling evaluation including computer-based photogrammetric analysis, visual ratings, and cumulative mass loss measurements. Then a correlation between the laboratory testing and in-situ sidewalk panel specimens is made via visual ratings.


Synthesis Of Zeolites With Controlled Defects By Understanding The Role Of Charge Balance In Zeolite Crystallization, Song Luo Feb 2023

Synthesis Of Zeolites With Controlled Defects By Understanding The Role Of Charge Balance In Zeolite Crystallization, Song Luo

Doctoral Dissertations

Zeolites are well-defined and ordered microporous crystalline materials constructed by the continuous linkage of corner sharing TO4 tetrahedra (taking T atoms (e.g., Si or Al) as the tetrahedral center). Due to the structural and compositional diversities and superior hydrothermal stability, zeolites have been broadly utilized to many industrial fields, including gas separation and catalysis heterogeneous catalysis. However, understanding zeolite crystallization mechanisms remains a tantalizing challenge, which causes challenges in tailoring this material for advanced applications. Raman spectroscopy has emerged as a powerful tool for probing medium-range (0.35 - 1 nm) structures. Since this scale is consistent with the micropore size …


Synthesis And Assembly Of Polymer Materials At Interfaces, Xiaoshuang Wei Oct 2022

Synthesis And Assembly Of Polymer Materials At Interfaces, Xiaoshuang Wei

Doctoral Dissertations

The overarching goal of the thesis is to understand growth and assembly of polymer materials at interfaces. Chapter 2 and Chapter 3 study simultaneous polymer growth and assembly at fluid interfaces, where in-situ photopolymerization and vapor phase deposition were utilized to grow polymers, respectively. Chapter 4 leverages capillary condensation to pattern polymer growth at solid substrates. Chapter 1 provides background information on polymer materials at interfaces, and vapor phase deposition method (initiated chemical vapor deposition, iCVD) to grow polymers. This chapter also reviews polymer thin film wetting, and colloidal assemblies at interfaces. In Chapter 2, we demonstrate the preparation …


Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian Oct 2022

Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian

Doctoral Dissertations

The self-assembly of charged macromolecules forms the basis of all life on earth. From the synthesis and replication of nucleic acids, to the association of DNA to chromatin, to the targeting of RNA to various cellular compartments, to the astonishingly consistent folding of proteins, all life depends on the physics of the organization and dynamics of charged polymers. In this dissertation, I address several of the newest challenges in the assembly of these types of materials. First, I describe the exciting new physics of the complexation between polyzwitterions and polyelectrolytes. These materials open new questions and possibilities within the context …


Quantifying Elasto-Adhesion And Fluid-Elastic Dynamics For Ultra-Soft Hydrogel Interfaces, Hongbo Fu Oct 2022

Quantifying Elasto-Adhesion And Fluid-Elastic Dynamics For Ultra-Soft Hydrogel Interfaces, Hongbo Fu

Doctoral Dissertations

Hydrogels are constructed with polymer networks swollen with water, which are soft and with much smaller shear moduli than bulk moduli. Due to the similar moduli to biological tissues, synthetic hydrogels have been used for biological applications. While interfacial properties are important for many of the applications of soft materials, quantifying these properties is challenging for ultra-soft materials. Ultra-softness causes difficulties in measuring interfacial properties with conventional force-based methods. For example, soft specimens deform largely under gravity and external forces, and thus the assumptions of the established methods are invalid. Additionally, many of the applications for hydrogels require them to …


Enabling Nanoimprint Lithography Techniques Across Multiple Manufacturing Processes, Vincent Einck Sep 2022

Enabling Nanoimprint Lithography Techniques Across Multiple Manufacturing Processes, Vincent Einck

Doctoral Dissertations

Advanced nanooptics in the areas of flat lenses, diffractive elements, and tunable emissivity require a route to high throughput manufacturing. Nanooptics are often demanding of high refractive index materials, nanometer precision and ease of fabrication. Nanoimprint lithography (NIL) is a low-cost, high throughput manufacturing technique beginning to be realized in commercial industry.1,2 The NIL process is an ideal manufacturing candidate due to its ability to have a fast process time, efficient use of materials, repeatability and high precision while also having wide diversity of potential structures and material choices. Appling NIL techniques to other facets of manufacturing enable the …


Additive Manufacturing Of Sub-Micron Features And Mechanical Linkages, David K. Limberg Jun 2022

Additive Manufacturing Of Sub-Micron Features And Mechanical Linkages, David K. Limberg

Doctoral Dissertations

In recent years material constraints have become the limiting factor in several fields, including batteries, robotics, and medicine, and these needs have prompted the development of materials with programmable properties. To this end, much effort has been dedicated to designing metamaterials that have unprecedented optical, mechanical, and thermal properties, along with systems for additive manufacturing to build their complex structures with high precision and throughput. The field of additive manufacturing has proved to be a platform for innovation across many industries yet is still limited with regards to feature sizes, print rates, and diversity of materials. Mechanical devices like linkages …


Phase Behavior Of Oppositely Charged Polymerized Ionic Liquids In Solution, Bulk, And Crosslinked Network States, Minjung Lee Jun 2022

Phase Behavior Of Oppositely Charged Polymerized Ionic Liquids In Solution, Bulk, And Crosslinked Network States, Minjung Lee

Doctoral Dissertations

Polymerized ionic liquids (PILs), a class of polyelectrolytes, are fascinating materials for various applications utilizing ion transport, especially due to their advantageous properties including negligible vapor pressure, low flammability, thermal stability, high conductivity, and wide electrochemical stability windows. Furthermore, PILs are tunable in their properties such as ionic conductivity, glass transition temperature (Tg), solubility, and (electro-)chemical stability. In this thesis, we focus on fundamental studies of phase behaviors of PILs in the solution and bulk states in chapters 2 and 3, respectively. Specifically, non-aqueous systems are used to study the effect of solvent quality in the regime …


Euplectella Aspergillum’S Natural Lattice Structure For Structural Design & Stability Landscape Of Thin Cylindrical Shells With Dimple Imperfections, Zoe Y. Sloane Mar 2022

Euplectella Aspergillum’S Natural Lattice Structure For Structural Design & Stability Landscape Of Thin Cylindrical Shells With Dimple Imperfections, Zoe Y. Sloane

Masters Theses

The first portion of this thesis assesses the structural application of a bracing design inspired by the deep-sea sponge, Euplectella Aspergillum. Many studies have investigated the natural strength found in the unique skeletal structure of this species. The braced design inspired by the sponge features square frames with two sets of cross-braces that are offset from the corners of each frame, creating a pattern of open and closed cells. This study reports the results of multiple Finite Element Analysis (FEA) computations that compare the described bracing pattern to a more common bracing design used in structural design. The designs …


New Isomeric Silicones: Synthesis, Compositions And Surface Properties, Yan Cong Mar 2022

New Isomeric Silicones: Synthesis, Compositions And Surface Properties, Yan Cong

Doctoral Dissertations

This dissertation presents research performed in the field of silicone polymer science, which refers to polymers with alternating silicon-oxygen backbones. Three research topics will be explored. The first topic involves the synthesis of trimethylsiloxysilsesquioxane (MT) copolymers with vinyl and hydride functionalities as reactive liquid silicone precursors. The second topic describes titration of dimethylsiloxy (D) composition into trimethylsiloxysilsesquioxane (MT) copolymers for the purpose of controlling the mechanical properties and thermal stabilities of the material. The last topic explores the modification of hydrophobic silicone surfaces with oxygen plasma to form silica-like, hydrophilic surfaces and the behaviors of hydrophobic recovery. The first chapter …


Solidification Experiments And Magnetohydrodynamic Models In Electromagnetic Levitation, Gwendolyn Bracker Mar 2022

Solidification Experiments And Magnetohydrodynamic Models In Electromagnetic Levitation, Gwendolyn Bracker

Doctoral Dissertations

Electromagnetic levitation (EML) is a technique for containerless processing. The unique environment of containerless processing allows for the study of highly reactive melts at elevated temperatures. In containerless processing, the interface between a melt and its container is removed, reducing chemical contamination. In addition, levitation techniques reduce the available heterogeneous nucleation sites, providing greater access to the undercooled region for solidification studies. Levitation techniques provide the environment to study the fundamental behavior and thermophysical properties of liquid metals. During electromagnetic levitation experiments, magnetohydrodynamic flow is driven in the sample by the electromagnetic force field. This flow can have various effects …


Synthesis, Fabrication, And Assembly Of Mesoscale Polymer Filaments, Dylan M. Barber Mar 2022

Synthesis, Fabrication, And Assembly Of Mesoscale Polymer Filaments, Dylan M. Barber

Doctoral Dissertations

Mesoscale materials, with feature sizes in the range of one hundred nanometers to tens of micrometers, are ubiquitous in Nature. In organisms, mesoscale building blocks connect the properties of underlying molecular and nanoscructures to those of macroscale, organism-scale materials through hierarchical assemblies of recurring structural motifs. The collective action of large numbers of mesoscale features can afford stunning features like the structural color of the morpho butterfly wing, calcium ion-mediated movement in muscle, and wood structures like xylem that can support enormous external compressive loads and negative internal pressure to transport nutrients throughout an organism. In synthetic systems, the design, …


Tailoring Interfaces And Composition For Stable And Efficient Perovskite Solar Cells, Hamza Javaid Feb 2022

Tailoring Interfaces And Composition For Stable And Efficient Perovskite Solar Cells, Hamza Javaid

Doctoral Dissertations

Metal halide perovskite solar cells (PSCs) have revolutionized the field of thin film photovoltaics. Within a decade, the power conversion efficiencies (PCEs) have increased at a phenomenal rate, rising from 3.8% to more than 25% in single-junction devices, moving them ahead of the current silicon-based technology. The high efficiencies of perovskite solar cells (PSCs) and their other unique properties arise from a combination of organic and inorganic components and electronic-ionic conduction, making them excellent candidates for a plethora of applications. However, PSCs face a significant—and ironic—roadblock to commercialization: these light-harvesting materials degrade under sunlight—the very condition they would need …


Development Of Crosslinking Technologies For Waterborne & Powder Coatings, Mengfei Huang Feb 2022

Development Of Crosslinking Technologies For Waterborne & Powder Coatings, Mengfei Huang

Doctoral Dissertations

Waterborne coatings and powder coatings are fast-growing sectors of the world coating market due to their environmentally friendliness as they have low or zero volatile organic compounds (VOCs) emission. However, compared with solventborne coatings, significant limitations need to be overcome to enable their broad applications. My dissertation will discuss several novel crosslinking strategies for waterborne and powder coating that could enable curing on-demand at ambient conditions, with facile polymerization and easy processing, and ultimately, exhibit a high degree of crosslinking and excellent performance that is comparable to solventborne coatings. We introduced and demonstrated the anionic polymerization mechanism and the high …


Designing Nonflammable Polymers And Blends Containing Deoxybenzoin Derivatives, Elizabeth Stubbs Feb 2022

Designing Nonflammable Polymers And Blends Containing Deoxybenzoin Derivatives, Elizabeth Stubbs

Doctoral Dissertations

The importance of synthetic polymers in everyday life continues to grow, owing to their societal importance for improving our standard-of-living and enabling advances spanning medicine, electronics, construction materials, transportation. While niche applications occupy a small fraction of the overall volume of polymers produced, large scale applications tend to employ lower cost materials, such as polyethylene, polypropylene, and polystyrene. In addition to environmental considerations connected to these polymerized hydrocarbons, produced in excess of 380 million tons per year worldwide, their inherent flammability creates additional requirements associated with their manufacturing and use. Societal benefits of such polymers are extensive, and thus, there …


Towards Higher Power Factor In Semiconductor Thermoelectrics: Bandstructure Engineering And Potential Barriers, Adithya Kommini Oct 2021

Towards Higher Power Factor In Semiconductor Thermoelectrics: Bandstructure Engineering And Potential Barriers, Adithya Kommini

Doctoral Dissertations

To keep up with the current energy demand and to sustain the growth requires efficient use of existing resources. One of the ways to improve efficiency is by converting waste heat to electricity using thermoelectrics. Thermoelectric devices work on the principle of Seebeck effect, where an applied temperature difference across the material results in a potential difference in the material. The possibility of drastic improvements in the efficiency of thermoelectric (TE) devices using semiconductor nanostructured materials renewed interest in thermoelectrics over the last three decades. Introducing confinement, interfaces, and quantum effects using nanostructures for additional control of charge and phonon …


Advanced Materials Design Using Application-Based Processing Techniques, Daniel S. Camarda Oct 2021

Advanced Materials Design Using Application-Based Processing Techniques, Daniel S. Camarda

Doctoral Dissertations

This dissertation pertains to generating advanced materials using application-based processing techniques. First, billets consisting of PTFE sintering powders are evaluated using Thermomechancal Analysis. It was found that both shape change and volume change are associated with enthalpic and entropic recoil, respectively. These phenomena, due to melting and stored energy during the powder compaction process, were found to be molecular weight dependent. Additionally, kinetics of the recovery and sintering process were found to be slower in blended specimens than pure samples. Next, the creation of graft copolymers by selectively grafting a second polymer to the amorphous fraction of a semi-crystalline polymer …


Extracellular Polymeric Substances In Oxygenic Photogranules: Investigation Of Their Role In Photogranulation In A Hydrostatic Environment, Wenye Camilla Kuo-Dahab Sep 2021

Extracellular Polymeric Substances In Oxygenic Photogranules: Investigation Of Their Role In Photogranulation In A Hydrostatic Environment, Wenye Camilla Kuo-Dahab

Doctoral Dissertations

The purpose of this dissertation was to assess the critical role of extracellular polymeric substances (EPS) in the photogranulation of activated sludge, in a hydrostatic environment. The first section evaluates the fate and dynamics of different fractions of EPS in sludge-based photogranulation under hydrostatic conditions. The study shows that during the transformation of activated sludge into a photogranular biomass, sludge’s base-extractable proteins selectively degrade. Strong correlations between base-extracted proteins and the growth of chlorophyll a and chlorophyll a/b ratio suggest that the bioavailability of this organic nitrogen is linked with selection and enrichment of filamentous cyanobacteria under hydrostatic conditions. The …


Tall Timber In Denver: An Exploration Of New Forms In Large Scale Timber Architecture, Andrew P. Weuling Jul 2021

Tall Timber In Denver: An Exploration Of New Forms In Large Scale Timber Architecture, Andrew P. Weuling

Masters Theses

Wood has been utilized by humans for thousands of years in the construction of our built environment. More recently, our expanded understanding of the material and the advancement of engineered wood have allowed us to use wood like never before. Concrete and steel, however, have emerged as the main materials used in large scale construction in the late 19th and 20th Centuries. As we are battling and searching for solutions to climate change, the importance of wood in large scale construction has increased as not only is its carbon intensity is lower than steel and concrete, but its …


Designing Stimuli-Responsive Nanocomposites To Investigate Interface Dynamics, Huyen Vu Jul 2021

Designing Stimuli-Responsive Nanocomposites To Investigate Interface Dynamics, Huyen Vu

Doctoral Dissertations

Inspired by nature, this research focuses on designing multifunctional renewable nanocomposites with high toughness and stimuli-responsiveness. In recent years, cellulose nanocrystals (CNCs) have been explored due to their abundance, renewable resource, and unique mechanical strength and structural coloration. CNCs naturally self-assemble into the helicoidal (Bouligand) structure that effectively endure high impacts but is brittle without an attendant soft phase. A thermoresponsive polymer, poly(diethylene glycol methyl ether methacrylate) (PMEO2MA), was incorporated into CNCs via evaporation-induced self-assembly to improve toughness of the resulting nanocomposites and to study responses in polymer dynamics under varying temperature and humidity conditions. To study microscopic …


Thermoelectric Transport In Disordered Organic And Inorganic Semiconductors, Meenakshi Upadhyaya Jul 2021

Thermoelectric Transport In Disordered Organic And Inorganic Semiconductors, Meenakshi Upadhyaya

Doctoral Dissertations

The need for alternative energy sources has led to extensive research on optimizing the conversion efficiency of thermoelectric (TE) materials. TE efficiency is governed by figure-of-merit (ZT) and it has been an enormously challenging task to increase ZT > 1 despite decades of research due to the interdependence of material properties. Most doped inorganic semiconductors have a high electrical conductivity and moderate Seebeck coefficient, but ZT is still limited by their high lattice thermal conductivity. One approach to address this problem is to decrease thermal conductivity by means of alloying and nanostructuring, another is to consider materials with an inherently low …