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Solid oxide electrolysis cells (SOECs) and solid oxide fuel cells (SOFCs) are the leading high-temperature devices to realize the global “Hydrogen Economy”. These devices are inherently multi-material (ceramic and cermets). They have multi-scale, multilayer configurations (a few microns to hundreds of microns) and different morphology (porosity and densification) requirements for each layer. Adjacent layers should exhibit chemical and thermal compatibility and high-temperature mechanical stability. Added to that is the need to stack many cells to produce reasonable power. The most critical barriers to widespread global adoption of these devices have been their high cost and issues with their reliability and durability. Given their complex structure and stringent requirements, additive manufacturing (AM) has been proposed as a possible technological path to enable the low-cost production of durable devices to achieve economies of scale. However, currently, there is no single AM technology capable of 3D printing these devices at the complete cell level or, even more difficult, at the stack level. This article provides an overview of challenges that must be overcome for AM to be a viable path for the manufacturing of SOECs and SOFCs. A list of recommendations is provided to facilitate such efforts.

The brick-and-mortar structure inspired by nature, such as in nacre, is considered one of the most optimal designs for structural composites. Given the large number of design possibilities, extensive computational work is required to guide their manufacturing. Here, we propose a computational framework that combines statistical analysis and machine learning with finite element analysis to establish structure–property design strategies for brick-and-mortar composites. Approximately 20,000 models with different geometrical designs were categorized into good and bad based on their failure modes, with statistical analysis of the results used to find the importance of each feature. Aspect ratio of the bricks and horizontal mortar thickness were identified as the main influencing features. A decision tree machine learning model was then established to draw the boundaries of good design space. This approach might be used for the design of brick-and-mortar composites with improved mechanical properties.Brick-and-mortar composite structures found in nature are known for their superior mechanical performance. Here, computational approaches are used to understand the key design features that control mechanical behavior, providing guidance for the design of improved composites.

Piezoelectric polymer nanofibers are promising for wearable electronics due to their mechanical compliance and electromechanical responsiveness. Poly(vinylidene fluoride)‐trifluoroethylene (PVDF‐TrFE) is widely used for its ferroelectric β ‐phase and favorable piezoelectric properties, yet its limited elasticity hinders applications in soft bioelectronics. Electrospun PVDF‐TrFE mats can stretch through fiber rearrangement but lack true elastic recovery unless molecular interactions and junctions are modified. Achieving nanofiber networks that are both stretchable and piezoelectrically stable under cyclic strain remains a challenge. Here, we report a strategy combining PVDF‐TrFE with a small fraction of poly(ethylene glycol) bis(amine) (PEG‐diamine) and thermal annealing to form fused nanofibrous mats with enhanced elasticity and stable piezoelectric output. The blended mats doubled the strain‐to‐failure (~30%) compared to pure PVDF‐TrFE (~14%) and showed Mullins‐like elastic recovery up to approximately 9% with reduced hysteresis. Piezoelectric response improved by approximately 25% in peak voltage (~150 mV), with greater signal stability. Structural analyses (Fourier‐transform infrared [FTIR], differential scanning calorimetry [DSC], and X‐ray diffraction [XRD]) confirmed increased β ‐phase content and selective cross‐linking in amorphous domains without compromising ferroelectric order. This work demonstrates a scalable material‐based approach to improve elasticity and durability in electrospun piezoelectric fibers, enabling stretchable and skin‐conformable sensors for smart fabrics, wearable health monitors, and energy harvesting.

Printing functional devices on flexible substrates requires printing of high conductivity metallic patterns. To prevent deformation and damage of the polymeric substrate, the processing (printing) and post-processing (annealing) temperature of the metal patterns must be lower than the glass transition temperature of the substrate. Here, a hybrid process including deposition of a sacrificial blanket thin film, followed by room environment nozzle-based electrodeposition, and subsequent etching of the blanket film is demonstrated to print pure and nanocrystalline metallic (Ni and Cu) patterns on flexible substrates (PI and PET). Microscopy and spectroscopy showed that the printed metal is nanocrystalline, solid with no porosity and with low impurities. Electrical resistivity close to the bulk (~2-time) was obtained without any thermal annealing. Mechanical characterization confirmed excellent cyclic strength of the deposited metal, with limited degradation under high cyclic flexure. Several devices including radio frequency identification (RFID) tag, heater, strain gauge, and temperature sensor are demonstrated.

DNA has long been viewed as a promising material for nanoscale electronics, in part due to its well‐ordered arrangement of stacked, pi‐conjugated base pairs. Within this context, a number of studies have investigated how structural changes, backbone modifications, or artificial base substitutions affect the conductivity of DNA. Herein, we present a comparative study of the electrical properties of both well‐matched and perylene‐3,4,9,10‐tetracarboxylic diimide (PTCDI)‐containing DNA molecular wires that bridge nanoscale gold electrodes. By performing current‐voltage measurements for such devices, we find that the incorporation of PTCDI DNA base surrogates within our macromolecular constructs leads to an approximately 6‐fold enhancement in the observed current levels. Together, these findings suggest that PTCDI DNA base surrogates may enable the preparation of designer DNA‐based nanoscale electronic components. Better with bases: The electrical properties of well‐matched DNA molecular wires and perylene‐3,4,9,10‐tetracarboxylic diimide‐containing DNA molecular wires were comparatively evaluated. The incorporation of PTCDI DNA base surrogates substantially enhances the current levels measured for the described constructs. These findings may ultimately facilitate the design of DNA‐based nanoscale electronic components.

In order to understand the tensile fatigue characteristics of single carbon nanotube yarn (CNTY), experiments of fatigue loading and residual strength after different fatigue cycles were conducted. Results show that the tensile fatigue limit of the CNTY is ~ 68% of ultimate tensile strength (UTS). SEM figures show a typical fatigue process including crack initiation, crack propagation, and sudden fracture. Helix angles on the surface of CNTY decreased when the yarn underwent a certain number of tension–tension fatigue loading cycles, and the yarn was increasingly strengthened. Specifically, the strength and modulus of CNTY were increased by 21% and 468%, respectively, when the yarn was subjected to a 10 5 fatigue cycles at 68% UTS. The increase in residual specific strength after cyclic loading was found out to be the reason for the inflection point of the S–N curve. However, there were gaps between the surface layer and inner layer in the yarn. Cracks initiated along the gaps by shear force and friction during cyclic loading. Then, the failure of the inner CNT layers was caused by stress concentration at one of the relatively large cracks. A sudden fracture of the CNTY occurred eventually.

Porous yttriastabilized zirconia (YSZ), in a composite with NiO, is widely used as a cermet electrode in solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs). Given cycles of high temperature in these energy devices, mechanical integrity of the porous YSZ is critical. Pore morphology, as well as properties of the ceramic, ultimately affect the mechanical properties of the cermet electrode. Here, we fabricated porous YSZ sheets via freezing of an aqueous slurry on a cold thermoelectric plate and quantified their flexural properties, both for as-fabricated samples and samples subjected to thermal shock at 200 °C to 500 °C. Results of this work have implications for the hydrogen economy and global decarbonization efforts, in particular for the manufacturing of SOFCs and SOECs.

We report on the synthesis and the mechanical characterization of an alginate-collagen fibril composite hydrogel. Native type I collagen fibrils were used to synthesize the fibrous composite hydrogel. We characterized the mechanical properties of the fabricated fibrous hydrogel using tensile testing; rheometry and atomic force microscope (AFM)-based nanoindentation experiments. The results show that addition of type I collagen fibrils improves the rheological and indentation properties of the hydrogel.

Solid oxide electrolysis cells (SOECs) and solid oxide fuel cells (SOFCs) are the leading high-temperature devices to realize the global “Hydrogen Economy”. These devices are inherently multi-material (ceramic and cermets). They have multi-scale, multilayer configurations (a few microns to hundreds of microns) and different morphology (porosity and densification) requirements for each layer. Adjacent layers should exhibit chemical and thermal compatibility and high-temperature mechanical stability. Added to that is the need to stack many cells to produce reasonable power. The most critical barriers to widespread global adoption of these devices have been their high cost and issues with their reliability and durability. Given their complex structure and stringent requirements, additive manufacturing (AM) has been proposed as a possible technological path to enable the low-cost production of durable devices to achieve economies of scale. However, currently, there is no single AM technology capable of 3D printing these devices at the complete cell level or, even more difficult, at the stack level. This article provides an overview of challenges that must be overcome for AM to be a viable path for the manufacturing of SOECs and SOFCs. A list of recommendations is provided to facilitate such efforts.

Nanomechanics of individual collagen fibrils govern the mechanical behavior of the majority of connective tissues, yet the current models lack significant details. Majority of the current models assume a rod-shape molecule with homogenous mechanical properties. Recent X-ray crystallography revealed significantly different microstructures in the D-period of collagen microfibrils, markedly different from the conventionally assumed rod-shaped molecule. Motivated by this recent microstructure, the nanomechanics of hydrated collagen molecules are investigated through molecular dynamics simulations. The results reveal significant mechanical heterogeneity in individual collagen molecules, which is expected to significantly impact the biomechanics of collagen fibrils in healthy and diseased tissues.