Translational Materials Research

Within the last decade, novel materials concepts and nanotechnology have resulted in a great increase of the conversion efficiency of thermoelectric materials. Despite this, a mass market for thermoelectric heat-to-electricity conversion is yet to be opened up. One reason for this is that the transfer of the lab records into fabrication techniques which enable thermoelectric generator modules is very challenging. By closing the gap between record lab values and modules, broad industrial applications may become feasible.

In this review, we compare three classes of materials, all designed for medium-high to high temperature applications in the field of waste heat recovery: skutterudites, half-Heusler compounds, and silicon-based materials. Common to all three classes of thermoelectric materials is that they are built from elements which are neither scarce (e.g. tellurium) nor toxic (e.g. lead) and therefore may be the foundation of a sustainable technology. Further, these materials can provide both, n-type and p-type materials with similar performance and thermomechanical properties, such that the fabrication of thermoelectric generator modules has already been successfully demonstrated. The fabrication processes of the presented materials are scalable or have already been scaled up.

The availability of thermoelectric materials is only one important aspect for the development of thermoelectric generator modules and heat conversion systems based on this technology. The design and configuration of the thermoelectric generator modules is similarly important. Hence, basic considerations of module configuration and different fundamental layouts of the thermoelectric heat-to-electricity conversion system are discussed within an additional chapter of this review.

Transparent paper made of cellulose for next generation 'green' electronic devices is a completely new concept that has attracted great attention over the past decade due to a variety of prominent properties of cellulose such as its natural origin, environmental safety and renewability. Various proof-of-concept transparent paper-based electronics have been demonstrated by scientists from all over the world. In this article, we first discuss the natural cellulose-based materials for transparent paper. We then summarize recent advances in the fabrication of transparent paper, including filtration, casting, extrusion and impregnation. The latest developments in transparent and flexible paper electronic devices are also demonstrated, such as photovoltaic devices, transistors, organic light emitting diodes and displays. Finally, we discuss the economically efficient routes for the mass production of transparent paper.

An efficient strategy for the up-scaling of processing technology for inkjet printing of silver nanoparticle inks towards industrially relevant manufacturing volumes is described. This has been demonstrated by the roll-to-roll production of fine conductive patterns on polymer foils. Starting with small-scale benchmarking to identify the most suitable ink–substrate combination from a range of commercial products, the processing conditions for inkjet printing and sintering were continuously optimized during three consecutive stages. During each iteration, the scale of the experiments in terms of complexity, time requirement and materials usage was increased, thereby more closely resembling the final industrial-scale production conditions. This increased effort was, however, counterbalanced by limiting the number of necessary experiments by purposeful selection based on the results obtained at the lower levels. In addition, the outcome of each previous iteration round served as a starting point for the optimization during the next higher stage. In this way, it was possible to strongly restrict the number of experiments to obtain valuable information about the most ideal conditions at the final stage, which was a roll-to-roll pilot production line. Following this approach, large-area functional conductive structures on plastic foils could be prepared in a continuous manner at process speeds of up to 10 m min^–1. These samples showed promising properties for application in printed electronic devices.

There is a growing consensus that future specific energy improvements in Li–ion batteries may not ever be sufficient to allow mass market adoption of electric vehicles, as we approach the physical limits of storage capacity of current Li–ion batteries. Several 'beyond li-ion' (BLI) chemistries are being explored as possible high-energy-density alternatives to Li–ion batteries. In this article, we focus on analyzing three BLI battery systems: Li–air, Li–sulphur and Na–air. We present a comprehensive discussion of the fundamental material challenges associated with these chemistries and document the progress being made in translating next-generation battery systems from the lab to the market. We also carry out a critical examination of the hype surrounding emerging battery technologies. We report, for the first time, a hype chart for batteries akin to those popularized by Gartner, Inc. for emerging technologies. We expect this hype chart to give us better insights on the respective standings of the current BLI technologies.

The application potential of silver (Ag) nanoparticles as low-emissivity (low-e) coating materials has been discussed. Ag nanoparticles with an average diameter of about 50 nm were prepared via a wet-chemical method and applied on the surface of glass by spin coating. The as-prepared Ag nanoparticle films showed a typical surface emissivity of about 0.793, compared to about 0.837 of the plain glass substrate. After a mild heat treatment at 200 °C, the annealed Ag nanoparticle films showed a substantially reduced surface emissivity value as low as 0.015. The corresponding structural evolution of Ag nanoparticle films during the heat treatment and its effect on the surface emissivity were discussed by means of scanning electron microscopy. The results indicated that forming an interconnected, porous network of Ag nanoparticles is essential for achieving the low-e effect for this material. By applying such low-e coatings, the heat loss through a double-glazed window can be reduced by about 35% (U-value reduction from 2.75 to 1.78 W (m²K)⁻¹). This work may inspire further efforts to address the energy efficiency issues in the building sector by taking the advantage of nanomaterials and nanotechnology.

Redox-active organic molecules (ROMs) are an attractive alternative to the inorganic, charge-storing compounds typically used in modern batteries as they exhibit potentially superior electrochemical properties, a wide materials design space, and an abundance of raw constituent materials, which, in turn, may open pathways to inexpensive energy storage. However, as most of these molecules are not produced on a commercial scale, assessing the cost proposition of new ROMs is a challenging but critical task for projecting the economic viability of incipient battery technologies. Here, we evaluate different cost estimation methods, explain their application, and determine their practicality for newly developed materials. For this purpose, we use anthraquinone disulfonic acid as a benchmark material, as this compound has been proposed for redox flow batteries and is already produced on an industrial scale. Our results show that simple cost estimation methods are easy to apply but ultimately fail to provide reliable cost information due to their limited accuracy. In contrast, more advanced methods offer more consistent and precise cost estimates but depend on detailed process knowledge rarely obtainable for new organic molecules. Furthermore, our cost analysis proves the feasibility of ROMs at the costs necessary to enable grid storage technologies that meet established cost targets.

Bioactive glasses are able to chemically bond to hard and soft tissues and have been proposed and used for tissue regeneration in several dentistry and medical applications. However, the majority of bioactive glass compositions do not support prolonged or repeated heat treatments, since these procedures often result in uncontrolled crystallization, which usually degrade their mechanical properties and, in most instances, substantially diminish their bioactivity. Therefore, the manufacturing of 3D devices, fibers or scaffolds, which aim to expand the usage of these materials, is a challenging task. To overcome this phenomenon, a new bioactive glass composition was recently developed at the Vitreous Materials Laboratory (LaMaV—UFSCar, Brazil) and licensed to the start-up company VETRA. This new bioactive glass composition shows high stability against crystallization coupled with high bioactivity, which allows the development of bioactive fibers, meshes and other complex 3D shapes. In addition, this bioactive glass has an elevated bioactivity, is bioresorbable and flexible (in fiber form), which makes this glass a potential alternative for soft and hard tissue regeneration. In this article, we discuss this recent development and summarize the latest advances in testing the effectiveness of this new material in in vitro and in vivo tests. To date, the results indicate that this new glass composition presents a larger workability window, which allows the development of numerous medical devices. This feature combined with the high bioactivity of this new glass delivers a promising broad spectrum of applications as a material for tissue engineering.

Materials-based ventures face a high degree of technology uncertainty and market uncertainty when engaging in the technology entrepreneurial process. Recently, the lean startup methodology (LSM) has been introduced to practice and education as an integrated approach on how entrepreneurs can resolve these uncertainties when starting up a business. While the literature provides examples of LSM's successful application in a range of application areas, its focus application tends to be on consumer software. The purpose of this article is to discuss the degree to which LSM can be applied to the context of technology entrepreneurship. We find that LSM has strengths in addressing market uncertainty, but is largely silent on addressing technology uncertainty. In situations of a low degree of technology readiness, strongly intertwined process and product innovation processes such as those common in materials translation, and of addressing business markets, LSM may not suffice. We discuss the case of competence leveraging as one where technology uncertainty is lower for materials companies and illustrate the benefits on LSM in this context.

Innovations in the physical sciences face unique challenges and barriers as they transition from concept to product, and finally to profitable business. Specifically, time horizons are much longer and early-stage capital needs are much higher than for alternative investments in, for example, information technology or consumer electronics. Universities with significant research programs in the physical sciences are most significantly affected as early-stage investors who are willing to accept high risk and the associated liquidity penalty become scarce. A potential solution to this dilemma is the implementation of a lab-to-market roadmap within the university infrastructure to align process, metrics and funding, with the goal of guiding technology translation in a disciplined fashion, while generating meaningful returns at low risk to the institution. Such a roadmap for early-stage technology entrepreneurship is described here, with start-up activity integrated into the universities' research activity and with a focus on three critical success factors: (1) a robust process for start-up activity; (2) an educational program that teaches the process and helps participants to implement it; and (3) an infrastructure that creates the appropriate environment for academic organizations to effectively develop innovations into products that are positioned to become great companies. For examples of the methodology, a case study for the start-up process (Cronos Integrated Microsystems) is reviewed and a successful lab-to-market case study at Duke University is also provided.

It is shown that water proton NMR can detect uncontrolled clustering of inert nanoparticles (NPs) formulated as aqueous suspensions. The clustering of NPs causes the compartmentalization of water molecules, leading to accelerated proton spin de-coherence, and hence, much faster water transverse relaxation rates. The results suggest that water proton NMR can be used to noninvasively inspect NP products by commercial end users and researchers.

The Joint Center for Energy Storage Research (JCESR) attempts to fuse together basic research, battery design, and pathways to market, bypassing the high-risks, high-costs, and market entry-challenges of sustainable energy technology. Focusing on JCESR's publications record, this paper highlights qualities of the Triple Helix model of government-university-firm interactions, particularly the nearly ten thousand instances of research collaboration, the nearly three thousand collaborative instances among JCESR's affiliated institutions and beyond, and the expanding disciplinary focus. These findings are confirmed with the first-ever survey of lithium-ion battery researchers. Despite intentions to commercialize battery technology in line with the tenets of the Triple Helix paradigm, battery storage research under JCESR remains primarily basic in orientation, thus diminishing opportunities for public-private research collaboration and commercialization. Nonetheless, JCESR provides a foundation for continued efforts to leverage synergies across the Triple Helix of battery storage research.

Detecting dynamic multi-scale human motion requires the stretchable strain sensor to possess outstanding properties in every aspect. Unlike conventional strain sensors which focus on changing conductive materials and preparing methods, we introduce a novel mechanical structure design to control the performance of the strain sensor. The performance of the device can be simply controlled by the structural design rather than complex materials adjustments. So the complexity of the material preparation will be greatly reduced, thus promotes the materials translation and production. By designing an asymmetric structure of elastomer substrate and protect layer with different adjustable parameters, the strain distribution in elastomer can be controlled, which finally change the performance of strain sensors. The experiment results illustrated our works on changing the stretchablity and sensitivity of the strain sensors. Application tests on human body including subtle-scale strain like pulse and large-scale strain like elbow bending are conducted to prove our capability for multi-scale motion detecting.

Redox-active organic molecules (ROMs) are an attractive alternative to the inorganic, charge-storing compounds typically used in modern batteries as they exhibit potentially superior electrochemical properties, a wide materials design space, and an abundance of raw constituent materials, which, in turn, may open pathways to inexpensive energy storage. However, as most of these molecules are not produced on a commercial scale, assessing the cost proposition of new ROMs is a challenging but critical task for projecting the economic viability of incipient battery technologies. Here, we evaluate different cost estimation methods, explain their application, and determine their practicality for newly developed materials. For this purpose, we use anthraquinone disulfonic acid as a benchmark material, as this compound has been proposed for redox flow batteries and is already produced on an industrial scale. Our results show that simple cost estimation methods are easy to apply but ultimately fail to provide reliable cost information due to their limited accuracy. In contrast, more advanced methods offer more consistent and precise cost estimates but depend on detailed process knowledge rarely obtainable for new organic molecules. Furthermore, our cost analysis proves the feasibility of ROMs at the costs necessary to enable grid storage technologies that meet established cost targets.

Additive manufacturing (AM), commonly referred to as 3D printing, is an innovative manufacturing technology that has the potential of disrupting the manufacturing industry on a scale not seen since the industrial revolution. It has the potential to move the current manufacturing paradigm of mass production of a single product to mass customization of products to meet individual customer needs. The rapid growth of interest in the additive manufacturing technologies is prompting the question of how to finance such unprecedented potential growth and use of the AM technology especially at the consumer, entrepreneurial and small and medium (SME) sized business level. In this paper, the authors propose a financing alternative that matches the democratizing of manufacturing process by additive manufacturing technologies. It focuses on the heavy consumer, entrepreneurial and SME involvement in the co-creation process of manufacturing using AM technologies. We emphasize crowdfunding as a viable funding vehicle for AM due to its similarity in character to AM. We show how AM innovators are utilizing crowdfunding that is fast democratizing the financing of innovation and allows consumers to become financiers and provide input to development of a product or service. Innovative crowdfunding matches well with the needs and the mass customization nature of characteristics of additive manufacturing technologies.

Additive manufacturing (AM) is an umbrella term for various layer-based manufacturing processes which are often portrayed as a new technological revolution. Despite impressive AM process developments the revenue of the AM industry is still a fraction of that of other manufacturing processes. This AM based revenue discrepancy raises many questions. They include: (1) What makes AM so special? and (2) How could the disruptive potential of AM be unlocked? We seek to add to the literature by providing an answer to elements of these questions through the development of a framework we call the 'Magic Cube'. We utilize the concept of vertical and horizontal innovation theory as one basis for this framework. Further we adopt a tension perspective on automation and individualisation drawn from operations research to develop a theoretical framework. The result is the 'Magic Cube', a tool that is designed to support researchers and practitioners in demonstrating the unique strengths of AM and its potential areas of application.