Editorial Cite This: Nano Lett. 2018, 18, 2187−2188
pubs.acs.org/NanoLett
Additive Manufacturing of Nano- and Microarchitected Materials
C
architectural control. Some interdisciplinary enabling technologies of nanoarchitected materials are in RF devices, materials for stealth technology, as well as frequency selective surfaces and absorbers. In the structural realm, nanoarchitected materials offer the combination of ultralightweight, stiffness, and strength for airborne applications, damage-tolerant hightemperature ceramics capable of stretching, and negative stiffness structures for absorbing shock and impact to name a few. Fabrication of these materials at dimensions that are useful and relevant to technologies requires manufacturing innovation. Scientific advances that can lead to manufacturing breakthroughs have made revolutionary societal and technological impacts throughout history: from mass-manufacturing of paper that enabled and simplified all facets of information technology like communication, printing, information delivery, and storage, to the development of silicon-based integrated circuits, which revolutionized fabrication, patterning, and processing of various thin films with ever-improving precision. Paper and silicon are examples of additive manufacturing, realized at differing length scales and for different functions, but with a lot of common features. They are based on robust materials’ platform generated at large scale, they “add” materials in layers through a variety of means (writing, painting, printing, deposition, growth, etc.), and they “pattern” them to control the information and functionality. Technological demands of the 21st century require realizing additive manufacturing at the nanoscale and in three dimensions. The emergence of a new field of 3D nano- and microarchitected structural “metamaterials” serves as a testament to the unique properties and combinations of decoupled properties that demand the development of additive manufacturing capabilities to be utilized in society. The multiscale nature and sophistication of these materials renders progress in this field to be possible only through massive interdisciplinary advances in materials science, chemistry, materials processing, optics, mechanics, applied physics, and broad-range computations. A recent report by Alliance for Manufacturing Foresight titled Metamaterials Manufacturing18 highlights the importance of developing manufacturing capabilities to create structural metamaterials, which requires a multidisciplinary, multiagency, federal research initiative. Devices and technologies generated with nanoscale additive manufacturing can fundamentally change conventional technologies in the realms of electronics, optoelectronics, energy storage and harvesting, biochemical sensors, and many others. One can imagine that these devices, powered, actuated, and controlled remotely, could be freely dispersed in foreign environments for ubiquitous sensing, injected into the bloodstream for whole body imaging, or integrated with molecules for designed drug delivery, among many other uses.
reating materials with a suite of designed properties is one of key challenges in our society. Solving this grand challenge will open pathways to create entirely new classes of materials, whose properties are determined a priori and are attained through a multiscale physically informed approach. These new material classes will offer breakthrough advances in almost every branch of manufacturing and technology from ultralightweight and damage-tolerant structural materials to safe and efficient energy storage, biomedical devices, biochemical and micromechanical sensors and actuators, nanophotonic devices, and textiles. Currently, manufacturing of materials occurs via the structure → processing → property pathway, which deterministically sets the material properties based on the processing history and the ensuing microstructure. Nanoarchitected materials enable decoupling properties that have historically been linked together, for example, strength and density, thermal conductivity and modulus, which shifts the material creation paradigm to properties → architecture → fabrication. When the characteristic dimensions of solid constituents that comprise architected materials are reduced to the nanoscale, many new phenomena emerge. Nearly all materials exhibit different properties at nanoscale; for example, smaller can be stronger,1−4 weaker,5 suppress brittle failure and induce ductility,6−8 couple into light to create three dimensional (3D) photonic crystals9,10 and negative refraction materials,11 and activate phonon scattering-driven thermal processes.12 Utilizing this emergence of new functionality at the nanoscale and proliferating these “size effects” onto 3D architectures have already proven successful; one notable example is the demonstration that hollow nanolattices with relative densities of ∼0.1%, made of 10 nm thick brittle ceramic, recovered after compression in excess of 50% without sacrifice in strength or stiffness13,14 and had an exceptionally low dielectric constant of 1.06 at 1 MHz.15 Similar exceptional recoverability was also found in nanoarchitectures made of metallic glasses, materials that are notorious for catastrophic failure via rapid shear band initiation and propagation.16 Another example is amorphous carbon nanolattices whose compressive strength approaches the ideal material strength.17 These materials simultaneously attained ultralight weight, high strength and stiffness, and in some cases, recoverability by combining the architecture and material size effect that emerges in nanomaterials. Manufacturing 3D nanoarchitectures will enable the creation of new classes of materials, which do not currently exist, that will be able to address multiple technological challenges, especially those where a property and density need to be decoupled from one another. Nanoarchitected materials represent a class of new “metamaterials” that can utilize the optimized nanometer-sized induced material properties, high surface area, and 3D architecture to enable distinct departure from existing material systems. It is the combination of hierarchical design and nanoscale dimensions of the solid that enables decoupling historically linked properties like strength and density through © 2018 American Chemical Society
Julia R. Greer, Associate Editor Jiwoong Park, Associate Editor
Published: April 11, 2018 2187
DOI: 10.1021/acs.nanolett.8b00724 Nano Lett. 2018, 18, 2187−2188
Nano Letters
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Editorial
AUTHOR INFORMATION
Notes
Views expressed in this editorial are those of the authors and not necessarily the views of the ACS.
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REFERENCES
(1) Greer, J. R.; De Hosson, J. T. M. Prog. Mater. Sci. 2011, 56, 654. (2) Uchic, M. D.; Shade, P.; Dimiduk, D. Annu. Rev. Mater. Res. 2009, 39, 361. (3) Dehm, G. Prog. Mater. Sci. 2009, 54, 664. (4) Greer, J. R.; Oliver, W. C.; Nix, W. D. Acta Mater. 2005, 53, 1821. (5) Gu, X. W.; Loynachan, C. N.; Wu, Z.; Zhang, Y.; Srolovitz, D. J.; Greer, J. R. Nano Lett. 2012, 12 (12), 6385. (6) Jang, D.; Li, X.; Gao, H.; Greer, J. R. Nat. Nanotechnol. 2012, 7, 594. (7) Chen, D. Z.; Jang, D.; Guan, K. M.; An, Q.; Goddard, W. A.; Greer, J. R. Nano Lett. 2013, 13, 4462. (8) Jang, D.; Greer, J. R. Nat. Mater. 2010, 9, 215. (9) Noda, S.; Tomoda, K.; Yamamoto, N.; Chutinan. Science 2000, 289, 604−606. (10) Arsenault, A. C.; et al. Nat. Mater. 2006, 5, 179−184. (11) Soukoulis, C. M.; Linden, S.; Wegener, M. Science (Washington, DC, U. S.) 2007, 315, 47−49. (12) Dou, N. G.; Minnich, A. J. Appl. Phys. Lett. 2016, 108, 011902. (13) Meza, L. R.; Das, S.; Greer, J. R. Science (Washington, DC, U. S.) 2014, 345, 1322. (14) Meza, L. R.; Zelhofer, A. J.; Clarke, N.; Mateos, A. J.; Kochmann, D. M.; Greer, J. R. Proc. Natl. Acad. Sci. U. S. A. 2015, 112, 11502. (15) Lifson, M.; Kim, M.-W.; Greer, J. R.; Kim, B.-J. Nano Lett. 2017, 17, 7737. (16) Liontas, R.; Greer, J. R. Acta Mater. 2017, 133, 393−407. (17) Bauer, J.; Schroer, A.; Schwaiger, R.; Kraft, O. Nat. Mater. 2016, 15, 438−443. (18) Spadaccini, C.; Bishop-Moser, J. Alliance for Manufacturing Foresight Report Number: MF-TR-2018−0301, 2018.
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DOI: 10.1021/acs.nanolett.8b00724 Nano Lett. 2018, 18, 2187−2188
