Material Point Of View Research Articles

Polymer Brush Made from Ionic Liquid and Its Anti-Biofilm Formation Behaviors By Environmental Biota in a Flow-Type Laboratory Biofilm Reactor

Biofilms are formed on materials surfaces by bacterial activities, which leads to the many kinds of contaminations and causes many industrial problems such as scale inside cooling water pipes, corrosion, hygiene issues at kitchens, dining, toilets, bath tubs, chronic diseases in medical fronts etc. To solve the industrial problems, many countermeasures have been proposed so far. The approach from the viewpoint of materials is one of the good ways to solve the biofilm problems. In this research, we investigated how biofilm behaviors formed in a flow type laboratory biofilm reactor (Fig.1) were affected by polymer brush coating of ionic liquids. As polymer brush, N-diethyl-N-(2-methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl) imide (ρDEMM-TFSI) was used with PMMA polymer brush coating as control. The polymer brush coated glass specimens were immersed in the laboratory biofilm reactor where environmental bacteria were mixed into water to form biofilms in the reactor. The specimens with biofilms were evaluated by Raman spectroscopy and optical microscopic observations. And the results were compared with those for PMMA polymer brush specimens. The results were also compared with those obtained by static immersion tests. As well as the results by static methods, ρDEMM-TFSI polymer coating specimens were sensitive to biofilm formation, being compared with the results for PMMA polymer brush coating specimens. The reason could be attributed to the ionic (anionic )polarization of ρDEMM-TFSI coating’s surfaces. However, those biofilms seemed to be concentrated at the vicinity of surfaces. Therefore, the biofilms restricted to the surface area might be removed easily. Figure 1

Pitch Derived Carbon As Light Weight and High-Power Sodium-Ion Battery Anode

Li-ion batteries (LIBs) are fulfilling the current need of humankind, the high abundance, and accessibility of sodium, making Na-ion batteries (NIBs) a promising LIBs supplement in the large-scale energy storage application.1, 2 However, the commercial success of NIBs demands an appropriate cathode and anode material. From the cathode material viewpoint, the literature reports suggest that O3/P2 type layered oxide can deliver a reasonable capacity with good cycling stability2. Graphite, the state-of-art anode material in LIBs is electrochemically inactive to intercalate Na-ions. Na-ion intercalation into graphite lattice is a thermodynamic driven process, where most Na-rich graphite intercalation compounds (GIC) prepared to date is NaC64 with a1 capacity of only 35 mAh g-1.3 However, Li-ion and K-ion form the stage one Li-GIC and K-GIC having the formula LiC6 and KC8, which makes them electronically active in Li- and K-ion battery, respectively. 4,5 To realize the large scale application of sodium-ion batteries, a stable, cost-effective anode is desired. Carbon-based anode materials are always attractive because of ease of fabrication, cost, and feasibility towards practical application. The pioneering work of Dahn and Stevens on hard carbon anode, reports the sodiation capacity of 300 mAh g-1 at room temperature.6 Later on, the hard carbon derived from different precursors such as a polymer, biomass, resin, etc., and applied as anode for Na-ion battery.7 However, hard carbon materials mostly suffer from poor carbon synthesis yield and high cost.8 Therefore, exploring cost-effective precursors and process is very crucial to realize the large scale application of NIB.Pitch is a potential low-cost precursor to synthesize soft carbon anode for NIBs. However, it does not exhibit decent Na-ion storage. Herein, we report the facile synthesis of pitch derived-binder less-metal free-freestanding anode for storing Na-ions by one-step pyrolysis process between the temperature range 700-1000 oC under nitrogen atmosphere. We replace conventional Cu-current collectors with carbon fiber (CFs). The electrode architecture not only eliminates the metallic current collector, conductive diluents and inactive organic binder but also provides an ideal porous network for sodium-ion and electrolyte diffusion into the bulk of the electrode. The freestanding electrode delivers a reversible capacity of 310 mAh g-1 in compare to 180 mAh g-1 for conventional electrode at the current density of 50 mA g-1. The cycling stability over 500 cycles (at 1 A g-1) and C-rate performance of freestanding anode dictate it as a promising anode for NIBs. The overall charge storage properties of conventional and freestanding-film are quantified into pseudocapacitive and diffusion-control Na+ intercalation. Further, the freestanding film is implemented as anode in order to realize its practical application in sodium-ion full cell. It is believed that the study may open up a new approach to modify the pitch based soft-carbon precursors as anode for low-cost, high-energy NIBs. Acknowledgments SG acknowledges MHRD, VKK acknowledges UGC-NET, Govt. of India, and SKM acknowledges Research Center Imarat (DRDO), Hyderabad under grant no. RCI/CAAT/8151/CARS-358 for financial support.

In Situ Absorption and Fluorescence Microspectroscopy Investigation of the Molecular Incorporation Process into Single Nanoporous Protein Crystals.

Protein crystals exhibit distinct three-dimensional structures, which contain well-ordered nanoporous solvent channels, providing a chemically heterogeneous environment. In this paper, the incorporation of various molecules into the solvent channels of native hen egg-white lysozyme crystals was demonstrated using fluorescent dyes, including acridine yellow G, rhodamine 6G, and eosin Y. The process was evaluated on the basis of absorption and fluorescence microspectroscopy at a single-crystal level. The molecular loading process was clearly visualized as a function of time, and it was determined that the protein crystals could act as nanoporous materials. It was found that the incorporation process is strongly dependent on the molecular charge, leading to heterogeneous molecular aggregation, which suggests host–guest interaction of protein crystals from the viewpoint of nanoporous materials.

From opt-in to obligation? Examining the regulation of globally operating tech companies through alternative regulatory instruments from a material and territorial viewpoint

ABSTRACTModern society’s ever-increasing reliance on technology raises complex legal challenges. In the search for an efficient and effective regulatory response, more and more authorities – in particular the European Union – are relying on alternative regulatory instruments (ARIs) when engaging big tech companies. Materially, this is a natural fit: the tech industry is a complex and rapidly-evolving sector and – unlike the rigid classic legislative process – ARIs allow for meaningful ex ante anticipatory constructions and ex post enforcement due to their unique flexibility. However, from a territorial point of view several complications arise. Although the use of codes of conduct to regulate transnational private actors has a rich history, the way in which such codes are set out under articles 40 and 41 of the EU’s GDPR implies a ‘hardening’ of these soft law instruments that has repercussions for their relationship to the principles of territorial jurisdiction. This contribution serves as a first step for further research into the relationship between codes of conduct, the regulation of the tech industry and the territorial aspects related thereto.

Sociedad moderna, mercado y fraude democrático

Abordamos la consistencia interna del fenómeno moderno derecho para poner de manifiesto las consecuencias posibles y efectivas de la vinculación esencialmente contradictoria entre, por un lado, la sociedad moderna, dado su carácter mercantil y, por ende, su estructura capitalista, y, por otro, su propio proyecto racionalizador (en su doble vertiente: derecho y ciencia). Desde el lado jurídico-político, esas consecuencias aparecen a modo de inevitable fraude democrático sistémico, y no ya desde un punto de vista material, como a menudo se reconoce (la realidad socio-económica impide la aplicación efectiva del derecho, de la forma derecho, en alguna medida –según se cree- realmente instaurada, establecida), sino fraude ante todo precisamente a nivel formal: lo que habría de ser el poder civil es sistemáticamente suplantado por un poder pseudo-civil. Muestra evidente de todo ello: nuestras supuestas leyes, supuestas constituciones, supuesto sistema de separación de poderes, supuestas declaraciones de derechos, supuestas democracias, etc. La perspectiva fenomenológica adoptada, con apoyo en el conjunto del pensamiento moderno, aunque de manera destacada en Kant y en Marx, muestra su rendimiento: deja ver al propio proyecto racionalizador moderno como el verdadero e inflexible patrón (auto-)crítico al que la propia sociedad moderna que le ha dado vida no tiene más remedio que rehuir, si no quiere perecer a manos de la revolución socialista.

Effect of Brownian Diffusion on Squeezing Elastico-Viscous Nanofluid Flow with Cattaneo-Christov Heat Flux Model in a Channel with Double Slip Effect

The present study deals with the analysis of heat transfer of the unsteady Maxwell nanofluid flow in a squeezed rotating channel of a porous extensile surface subject to the velocity and thermal slip effects incorporating the theory of heat flow intensity of Cattaneo-Christov model for the expression of the energy distribution in preference to the classical Fourier’s law. A set of transformations is occupied to renovate the current model in a system of nonlinear ordinary differential equations that are numerically decoded with the help of MATLAB integrated function bvp4c. The effects of various flow control parameters are investigated for the momentum, temperature and diffusion profiles, as well as for the wall shearing stress and the heat and mass transfer. The results are finally described from the material point of view. A comparison of heat flux models of Cattaneo-Christov and Fourier is also performed. An important result from the present work is that the squeezing parameter is strong enough in the middle of the channel to retard the fluid flow.

The experimental investigation of behaviour of expanded polystyrene (EPS)

Low-strength substrates and anthropogenic soils are always an issue in civil engineering. Based on the soil layer types, several methods could be used to improve the basic/foundation layer however it would be difficult to make sure if the specified requirements are achieved. Nowadays, Expandable Polystyrene (EPS) as a lightweight material found as a substitution for traditional methods like soil replacement, soil mixing, using piles driving and other treatment techniques. This paper will demonstrate the static properties of EPS foams in a view point of construction material which will be a key for the future study of these materials. A series of compression tests were carried out on different types of EPS foam to study the effect of EPS geofoam density on the mechanical behaviour of these materials.

Progress in supercapacitors: roles of two dimensional nanotubular materials.

Overcoming the global energy crisis due to vast economic expansion with the advent of human reliance on energy-consuming labor-saving devices necessitates the demand for next-generation technologies in the form of cleaner energy storage devices. The technology accelerates with the pace of developing energy storage devices to meet the requirements wherever an unanticipated burst of power is indeed needed in a very short time. Supercapacitors are predicted to be future power vehicles because they promise faster charging times and do not rely on rare elements such as lithium. At the same time, they are key nanoscale device elements for high-frequency noise filtering with the capability of storing and releasing energy by electrostatic interactions between the ions in the electrolyte and the charge accumulated at the active electrode during the charge/discharge process. There have been several developments to increase the functionality of electrodes or finding a new electrolyte for higher energy density, but this field is still open to witness the developments in reliable materials-based energy technologies. Nanoscale materials have emerged as promising candidates for the electrode choice, especially in 2D sheet and folded tubular network forms. Due to their unique hierarchical architecture, excellent electrical and mechanical properties, and high specific surface area, nanotubular networks have been widely investigated as efficient electrode materials in supercapacitors, while maintaining their inherent characteristics of high power and long cycling life. In this review, we briefly present the evolution, classification, functionality, and application of supercapacitors from the viewpoint of nanostructured materials to apprehend the mechanism and construction of advanced supercapacitors for next-generation storage devices.

State of the art on salt hydrate thermochemical energy storage systems for use in building applications

Abstract Thermal energy storage (TES) for storing low-grade energy is a promising approach to achieving higher energy security and minimizing greenhouse gas emissions. TES is shifting towards using thermochemical materials (TCM) since there are several advantages when compared to sensible or phase change materials. However, thermochemical energy storage (TCES) is more complex and thus has not yet been developed commercially. To further develop this technology and bring it closer to commercialization, there needs to be a merging of research from both material and system design viewpoints. At a material level, salt hydrates are considered the most suitable materials for residential applications due to their high energy density (400-870 kWh m−3) and low turning temperature (

Strategies for Designing Nanoparticles for Electro- and Photocatalytic CO2 Reduction.

Conversion of carbon dioxide (CO2 ) into value-added chemicals has attracted much attention because it can not only resolve global warming issues by reducing CO2 accumulation in the atmosphere, but also produce renewable hydrocarbon fuels that are important feedstocks for the chemical industry. Among the diverse approaches reported, CO2 reduction via electro- and photocatalytic methods is at the center of topics due to potential engineering of reaction performance through rational design of catalyst features. In this Minireview, we highlight recent strategies for designing nanoparticles to maximize the reaction efficiency and selectivity; from a materials viewpoint, these strategies can provide critical information to guide future research directions.

From LC‐polymers to Nanomedicines: Different Aspects of Polymer Science from a Materials Viewpoint

AbstractThis essay compiles the work of the author on i) liquid crystalline (LC)‐polymers (including LC‐elastomers, ferroelectric LCs and LC‐particles), on ii) switchable helical polymers, on iii) polymer based opals, on iv) organic – inorganic hybrids for the improvement of quantum dot light emitting diodes or for battery applications as well as on v) polymeric carriers for biomedical applications (e.g. nanomedicine for tumor‐immune‐therapy). From the chemical side this work is based the use of various polymerization techniques including—as more special techniques—a) “surfactant‐free emulsion polymerization” to prepare extremely monodisperse polymer colloids, b) controlled radical polymerization (RAFT) to prepare functional block‐copolymers and c) photoinitiated polymerization, to start polymerization and/or crosslinking at a defined space and time during processing.

Perspectives of Powder Metallurgy in the 2020s

In the automotive industry there is a clear trend towards alternative drivetrain systems, away from the classical internal combustion – gasoline or diesel - engines. This poses a challenge to the traditional markets of powder metallurgy, the ferrous precision parts for automotive engines and transmissions which form the major tonnage of today’s powder metallurgy [1, 2], but also the hardmetal tools for machining automotive components from stock material or for finishing [3]. To counter these trends, powder metallurgy can rely on its high flexibility regarding materials, geometries, processing and properties and finally applications, which enables PM to adapt itself to changing requirements in a changing industrial environment [4]. In the present article, examples are given both for PM precision parts and hardmetals but also functional materials such as soft magnetic composites. It is shown that the potential of ferrous PM parts regarding mechanical performance is still higher than currently used, high and graded density being attractive ways [5]. Also the use of advanced alloying systems offers economical and technical advantages and should enable PM to enter non-automotive markets for precision parts. In the hardmetal branch, non-automotive applications, e.g. in construction and mining, should be considered while from the material viewpoint replacing tungsten and in particular Co as binder metal are intensely studied. PM functional materials such as Fe-Ni, Fe-Co and in particular soft magnetic composites will find markets in electrical drive systems [6], enabling new designs for electric motors. On the other end of the spectrum, superhard rare earth magnets are regularly produced by the powder route. Finally, the multitude of additive manufacturing techniques offers chances for powder metallurgy since most of these processes start from metal powders [7]. In addition to the well known laser and electron beam based “direct” AM systems, also indirect, binder-based, variants are attractive, avoiding many problems encountered with the direct systems and enabling transfer of knowhow accumulated in metal injection moulding. In general, future will show how many other technologies and products has to offer in addition to the classical press-and-sinter routes which however will remain for their specific product groups. when designing your figures and tables, etc

Wielopostaciowość administracji publicznej w zakresie zarządzania kryzysowego

The paper presents the multiformity of public administration in crisis management from the subjective and material points of view. The provisions contained in the Act of 26 April 2007 on crisis management were analyzed. The act implies that the authorities of the general government and the local government at the level of the municipality and the district also are the crisis management authorities, and together with the subsidiary bodies create a specific system of public administration in this area. At the same time, it was pointed out that the statutory system of organs was incomplete, because in the crisis situations, specialist services (Police, State F ire Brigade, Army) and non-governmental organizations play a vital role. This multidimensionality allows distinguishing two groups of entities in crisis management: crisis management bodies and entities that perform tasks in crisis situations. In addition, the multiform nature of public administration in crisis management is evident in the presentation of this management in a material way: action preparation, civilian planning, risk prevention, fighting, reintegration.

Ferroelectric materials for neuromorphic computing

Ferroelectric materials are promising candidates for synaptic weight elements in neural network hardware because of their nonvolatile multilevel memory effect. This feature is crucial for their use in mobile applications such as inference when vector matrix multiplication is performed during portable artificial intelligence service. In addition, the adaptive learning effect in ferroelectric polarization has gained considerable research attention for reducing the CMOS circuit overhead of an integrator and amplifier with an activation function. In spite of their potential for a weight and a neuron, material issues have been pointed out for commercialization in conjunction with CMOS processing and device structures. Herein, we review ferroelectric synaptic weights and neurons from the viewpoint of materials in relation to device operation, along with discussions and suggestions for improvement. Moreover, we discuss the reliability of HfO2 as an emerging material and suggest methods to overcome the scaling issue of ferroelectrics.

Experimental and numerical study of the effect of using polyurethane instead of Teflon strip to simulate debonding defect in composite patch repairs aluminum plate under thermography inspection

In order to evaluate the capabilities of a non-destructive testing (NDT) technique for detecting the potential defects, the simulation conditions of manufactured defects must be correspond to real defects from shape and material point of view. Debonding defects are one of the most dangerous types of damage in composite patches for repairing cracks and defects in aircraft structures. In the case of real debonding defect, a thin air layer is embedded between the aluminum and the epoxy resin adhesive. In general, an artificial debonding is simulated by inserting Teflon (Polytetrafluoroethylene) tapes within the joint. This paper proposes the application of polyurethane (PU) instead of polytetrafluoroethylene (PTFE) strip to simulate debonding in composite when the specimen is inspected by thermography technique. The effect of the simulation of debonding defect at the edge of composite patch using polyurethane, Teflon tapes, and air gaps under thermography inspection is studied. Finite element modeling (FEM) and experimental verification of debonding at the edge of composite patch show a different efficiency of thermography inspection due to different thermal properties of Teflon, polyurethane, and air gap (real debonding). Comparing the performance of thermography inspection of composite patch with debonding simulated by PU, PTFE and air reveal the importance of simulating defects with realistic industrial configurations. Finite element analysis and experimental results show that using the proposed polyurethane sheet instead of Teflon sheet can provide much more realistic simulation of debonding defect in composite patch subjected to thermography inspection.

The rejuvenation on historical ruined vaults using lab analyses and numerical simulation

The exposure of historical masonry structures to climatic conditions and to user interventions, as well as the loss of their functionality over time, leads to the divergence of these structures from their original form and their dilapidation into ruin. With the aim of preserving such structures as cultural assets, the material characteristics of the original members are determined in a laboratory and their seismic capacity is determined by means of numerical analyses. The present study covers the works carried out to return to its original form a ruined vault in a historical castle that was built as a defensive structure in early 1800s, but which has in time lost its structural integrity. The study consisted of four stages: field work, laboratory analysis, preservation applications and a numerical simulation of the examined structure. The field study involves a visual inspection of structural deterioration and the gathering of representative samples from various points of the structure. The laboratory study includes mechanical, chemical and mineralogical analyses of the samples taken from the structure. Applications for the restoration of the structure to its original form are presented in the third stage, while the seismic performance level of the structure against seismic effects is defined. The study is important in its presentation of the process of reverting a vault structure that has suffered a deterioration of structural integrity over time into its original form from a geometric and material point of view. Such vaults are of particular importance as elements of castle structures that were used for defensive purposes at the time. The findings obtained from the research have been foreseen to contribute the understanding of structural behavior and intervention decisions in the restoration process of load-carrying brick vault systems in historical structures.

Covalent and Noncovalent Approaches to Rigid Coplanar π-Conjugated Molecules and Macromolecules.

Molecular conformation and rigidity are essential factors in determining the properties of individual molecules, the associated supramolecular assemblies, and bulk materials. This correlation is particularly important for π-conjugated molecular and macromolecular systems. Within such anindividual molecule, a coplanar conformation facilitates the delocalization of not only molecular orbitals but also charges, excitons, and spins, leading to synergistically ensembled properties of the entire conjugated system. A rigid backbone, meanwhile, imposes a high energy cost to disrupt such a favorable conformation, ensuring the robustness and persistence of coplanarity. From a supramolecular and material point of view, coplanarity and rigidity often promote strong intermolecular electronic coupling and reduce the energy barrier for the intermolecular transport of charges, excitons, and phonons, affording advanced materials properties in bulk. In this context, pursuing a rigid and coplanar molecular conformation often represents one of the primary objectives when designing and synthesizing conjugated molecules for electronic and optical applications. Two general bottom-up strategies-covalent annulation and noncovalent conformational control-are often employed to construct rigid coplanar π systems. These strategies have afforded various classes of such molecules and macromolecules, including so-called conjugated ladder polymers, graphene nanoribbons, polyacenes, and conformationally locked organic semiconductors. While pursuing these targets, however, one often confronts challenges associated with precise synthesis and limited solubility of the rigid coplanar systems, which could further impede their large-scale preparation, characterization, processing, and application. To address these issues, we developed and utilized a number of synthetic methods and molecular engineering approaches to construct and to process rigid coplanar conjugated molecules and macromolecules. Structure-property correlations of this unique class of organic materials were established, providing important chemical principles for molecular design and materials applications. In this Account, we first describe our efforts to synthesize rigid coplanar π systems fused by various types of bonds, including kinetically formed covalent bonds, thermodynamically formed covalent bonds, N→B coordinate bonds, and hydrogen bonds, in order of increasing dynamic character. The subsequent section discusses the characteristic properties of selected examples of these rigid coplanar π systems in comparison with control compounds that are not rigid and coplanar, particularly focusing on the optical, electronic, and electrochemical properties. For systems bridged with noncovalent interactions, active manipulation of the dynamic bonds can tune variable properties at the molecular or collective level. Intermolecular interactions, solid-state packing, and processing of several cases are then discussed to lay the foundation for future materials applications of rigid coplanar π conjugated compounds.

Social avoidance in depression: A study using a social decision-making task.

Depression significantly affects interpersonal functioning. Social avoidance may play an important role in depression, limiting opportunities and social skills acquisition, contributing to the maintenance of social difficulties. In the last few years, the need for studying social interactions using interactive tasks has been highlighted. This study investigated social avoidance in unmedicated depressed (n = 26) and matched healthy control (n = 26) participants, using a novel computerized social decision-making task (the TEAM task). In this task, participants choose between a social option (playing in a team with a coplayer) and an individual option (playing alone). Although the social option is more profitable from a material point of view, it can also be challenging because of social comparison and guilt feelings for failing the team. It was found that the higher the rank of the coplayer, the stronger the negative emotions (shame, guilt) reported by participants and the more they opted for the individual option. Depressed participants reported significantly less positive (happiness) and more negative (shame, guilt, disappointment) feelings regarding the task. Importantly, depressed participants chose the individual option significantly more often than controls, which led to lower gains in this group. Furthermore, as the task progressed, controls selected the individual option less often, whereas depressed participants selected the individual option more often. Our findings illustrate the importance of social avoidance in depression and how this behavior can lead to negative consequences. They also highlight the role of social comparison and guilt-related processes in underlying social avoidance in depression. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Experimental characterisation and computational modelling of cyclic viscoplastic behaviour of turbine steel

Fully reversed strain controlled low cycle fatigue and creep-fatigue interaction tests have been performed at ±0.7% strain amplitude and at three different temperatures (400 °C, 500 °C and 600 °C) to investigate the cyclic behaviour of a FV566 martensitic turbine steel. From a material point of view, the hysteresis mechanical responses have demonstrated cyclic hardening at the running-in stage and subsequent, hysteresis cyclic softening during the rest of the material life. The relaxation and energy behaviours have shown a rapid decrease at the very beginning of loading followed by quasi-stabilisation throughout the test. A unified, temperature- and rate-dependent viscoplastic model was then developed and implemented into the Abaqus finite element (FE) code through a user defined subroutine (UMAT). The material parameters in the model were determined via an optimisation procedure based on a genetic solver. The multi-axial form of the constitutive model developed was demonstrated by analysing the thermo-mechanical responses of an industrial gas turbine rotor subjected to in-service conditions. A sub-modelling technique was used to optimise the FEA. A 2D global model of the rotor with a 3D sub-model of the second stage of the low pressure turbine were then analysed in turn. The complex transient stress and accumulated plastic strain fields were investigated under realistic thermo-mechanical fatigue loading (start-up and shut-down power plant loads). The sub-model was then used for local analysis leading to identification of potential crack initiation sites for the presented types of blade roots.

Nanostructured colloidal quantum dots for efficient electroluminescence devices

The exceptional quality of light generated from colloidal quantum dots has attracted continued interest from the display and lighting industry, leading to the development of commercial quantum dot displays based on the photoluminescence down-conversion process. Beyond this technical level, quantum dots are being introduced as emissive materials in electroluminescence devices (or quantum dot-based light-emitting diodes), which boast high internal quantum efficiency of up to 100%, energy efficiency, thinness, and flexibility. In this review, we revisit various milestone studies regarding the core/shell heterostructures of colloidal quantum dots from the viewpoint of electroluminescence materials. Development of nanostructured colloidal quantum dots advanced from core/shell heterostructure, core/thick shell formulation, and delicate control of confinement potential shape has demonstrated close correlation of the photophysical properties of quantum dots with the performance of electroluminescence device, which provided useful guidelines on the heterostructured quantum dots for mitigating or eliminating efficiency limiting phenomena in quantum dot light emitting diodes. To enable practical and high performance quantum dot-based electroluminescence devices in the future, integration of design concepts on the heterostructures with environmentally benign systems will be crucial.