Transfer printing represents a set of techniques for deterministic assembly of micro‐and nanomaterials into spatially organized, functional arrangements with two and three‐dimensional layouts. Such ...processes provide versatile routes not only to test structures and vehicles for scientific studies but also to high‐performance, heterogeneously integrated functional systems, including those in flexible electronics, three‐dimensional and/or curvilinear optoelectronics, and bio‐integrated sensing and therapeutic devices. This article summarizes recent advances in a variety of transfer printing techniques, ranging from the mechanics and materials aspects that govern their operation to engineering features of their use in systems with varying levels of complexity. A concluding section presents perspectives on opportunities for basic and applied research, and on emerging use of these methods in high throughput, industrial‐scale manufacturing.
Transfer printing represents a set of techniques for deterministic assembly of micro‐ and nanomaterials into spatially organized, functional arrangements. The results provide not only test structures for scientific study, but also routes to high‐performance, heterogeneously integrated systems. This article summarizes recent advances in a variety of transfer printing techniques, from mechanics and materials aspects governing the operation, to engineering use in complex systems, to perspectives on high throughput, industrial‐scale manufacturing.
Quasi-binary thiophosphate-based solid electrolytes (SEs) are attracting substantial interest for lithium batteries due to their outstanding room temperature ionic conductivities. This work describes ...reactions occurring at the solid electrolyte (SE)/Au interface during Li deposition and stripping for two exemplary SE materials: β-Li3PS4 (β-LPS) and Li10GeP2S12 (LGPS). We used in situ Raman spectroscopy, along with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to evaluate potential-dependent changes in the chemistry of these materials at active electrode interfaces. For β-LPS, a partially reversible conversion of PS4 3– to P2S6 4– was found along with the formation of Li2S during Li deposition and stripping. In contrast, LGPS exhibited only irreversible changes at potentials below 0.7 V vs Li+/Li. The different behaviors likely relate to differences in the structures of the two SE materials and the availability of easily bridged anion components in close proximity. The work shows that SE integrity at interfaces can be altered by applied potential and illustrates important speciations for the interfacial structures that mediate their electrochemical activities.
Oxide-supported noble metal catalysts have been extensively studied for decades for the water gas shift (WGS) reaction, a catalytic transformation central to a host of large volume processes that ...variously utilize or produce hydrogen. There remains considerable uncertainty as to how the specific features of the active metal-support interfacial bonding-perhaps most importantly the temporal dynamic changes occurring therein-serve to enable high activity and selectivity. Here we report the dynamic characteristics of a Pt/CeO
system at the atomic level for the WGS reaction and specifically reveal the synergistic effects of metal-support bonding at the perimeter region. We find that the perimeter Pt
- O vacancy-Ce
sites are formed in the active structure, transformed at working temperatures and their appearance regulates the adsorbate behaviors. We find that the dynamic nature of this site is a key mechanistic step for the WGS reaction.
Biomimetic 4D printing Gladman, A Sydney; Matsumoto, Elisabetta A; Nuzzo, Ralph G ...
Nature materials,
04/2016, Volume:
15, Issue:
4
Journal Article
Peer reviewed
Shape-morphing systems can be found in many areas, including smart textiles, autonomous robotics, biomedical devices, drug delivery and tissue engineering. The natural analogues of such systems are ...exemplified by nastic plant motions, where a variety of organs such as tendrils, bracts, leaves and flowers respond to environmental stimuli (such as humidity, light or touch) by varying internal turgor, which leads to dynamic conformations governed by the tissue composition and microstructural anisotropy of cell walls. Inspired by these botanical systems, we printed composite hydrogel architectures that are encoded with localized, anisotropic swelling behaviour controlled by the alignment of cellulose fibrils along prescribed four-dimensional printing pathways. When combined with a minimal theoretical framework that allows us to solve the inverse problem of designing the alignment patterns for prescribed target shapes, we can programmably fabricate plant-inspired architectures that change shape on immersion in water, yielding complex three-dimensional morphologies.
Love et al focus on the preparation, formation, structure and applications of self-assembled monolayers formed from alkanethiols (and derivatives of alkanethiols) on gold, silver, copper, palladium, ...mercury and alloys of these metals. Love et al emphasize advances made in this area in the past five years (1999-2004).
Nonaqueous Zn-ion batteries are a promising candidate for a high-energy storage system to replace Li-ion batteries. Here, we report on CoS2 as a cathode material for Zn-ion batteries using nonaqueous ...electrolytes, one exhibiting a maximum capacity of 283 mAh/g. Compositional, valence state, and structural studies reveal Zn2+ de/intercalation mediated by reversible interconversions between 2S2– (sulfide) and S2 2– (disulfide) forms of sulfur, which is the first such known case operating in a multivalent system. Our findings suggest that anionic redox-active cathode materials offer considerable promise in realizing high capacities in multivalent batteries.
Conformal printing of electrically small antennas onto the convex and concave surfaces of hemispherical glass substrates is demonstrated. Their bandwidth approaches the fundamental limit for their ...size, offering nearly an order of magnitude improvement over rudimentary monopole designs.
We describe in this report the electrochemistry of Mg deposition and dissolution from the magnesium aluminum chloride complex (MACC). The results define the requirements for reversible Mg deposition ...and definitively establish that voltammetric cycling of the electrolyte significantly alters its composition and performance. Elemental analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDS) results demonstrate that irreversible Mg and Al deposits form during early cycles. Electrospray ionization mass spectrometry (ESI-MS) data show that inhibitory oligomers develop in THF-based solutions. These oligomers form via the well-established mechanism of a cationic ring-opening polymerization of THF during the initial synthesis of the MACC and under resting conditions. In contrast, MACC solutions in 1,2-dimethoxyethane (DME), an acyclic solvent, do not evolve as dramatically at open circuit potential. From these results, we propose a mechanism describing how the conditioning process of the MACC in THF improves its performance by both tuning the Mg:Al stoichiometry and eliminating oligomers.
All-solid-state Li-ion batteries afford possibilities to enhance battery safety while improving their energy and power densities. Current challenges for achieving high-performance all-solid-state ...batteries with long cycle life include shorting resulting predominantly from Li dendrite formation and infiltration through the solid electrolyte (SE) and increases in cell impedance induced by SE decomposition at the SE/electrode interface. In this work, we evaluate the electrochemical properties of two interlayer materials, Si and Li x Al(2–x/3)O3 (LiAlO), at the Li7P3S11 (LPS)/Li interface. Compared to the Li/LPS/Li symmetric cells in absence of interlayers, the presence of Si and LiAlO both significantly enhance the cycle number and total charge passing through the interface before failures resulting from cell shorting. In both cases, the noted improvements were accompanied by cell impedances that had increased substantially. The data reveal that both interlayers prevent the direct exposure of LPS to the metallic Li and therefore eliminate the intrinsic LPS decomposition that occurs at Li surfaces before electrochemical cycling. After cycling, a reduction of LPS to Li2S occurs at the interface when a Si interlayer is present; LiAlO, which functions to drop the potential between Li and LPS, suppresses LPS decomposition processes. The relative propensities toward SE decomposition follows from the electrochemical potentials at the interface, which are dictated by the identities of the interlayer materials. This work provides new insights into the phase dynamics associated with specific choices for SE/electrode interlayer materials and the requirements they impose for realizing high efficiency, long lasting all-solid-state batteries.
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