EDITORIAL pubs.acs.org/JPCL
Revealing the Art of Nanoscience The topics discussed in these Perspectives1,2 and other feature articles11,12 provide fundamental information on nucleation and growth processes, morphology and crystallinity, and the size-dependent properties of nanomaterials. These research efforts, aided by materials design, will dictate how scientists and engineers design next-generation electronic and optoelectronic devices.
People are amused by the colors of butterflies, captivated by the beauty of coral reefs, fascinated by rain drops rolling on the lotus leaf, and even perplexed by a gecko's feet. Many such wonders of nature are built upon the principles of nanotechnology, which render a specific property or functionality. The bottom-up approach adopted to construct various nanostructures allows these creatures to function effectively in their surroundings. Interest in creating nanostructured materials is not new. Ancient Romans, for example, synthesized metallic nanoparticles to use in stained glass windows. Colloidal chemistry, which dominated the early part of the last century, included the synthesis of metal nanoparticle and metal oxide suspensions. Today, we find many practical applications that are built upon the principles of chemistry and physics of nanomaterials. From catalyst particles to computer chips, nanostructures facilitate our day-to-day activities. In order to continue to design materials of controlled size, shape, and functionality, we need a better scientific understanding and new tools to probe structures at the nanometer scale. The Perspectives in the current issue focus on two separate topics that explore the basic aspects of nanoscience advances.1,2 In his Perspective, Ravishankar presents the salient features of modern-day transmission electron microscopy (TEM), which has become an indispensable tool in characterizing new nanoarchitectures.1 Our ability to image nanostructures in high resolution is a major driving force behind advances in nanoscience and nanotechnology. Many such images, in fact, have decorated the front covers of materials journals and are the biggest ambassadors for the emergence of the “Nano” field as a separate discipline. High-resolution imaging, coupled with other surface science techniques, provides additional information such as crystal structure and elemental composition. Some recent papers highlight the importance of TEM in understanding the growth and morphology of nanostructures.3-5 Scanning tunneling microscopy (STM) is also a technique that can directly relay information about the reactive species and active catalytic sites and thus provide atomic-scale visualization of surface reactions. Some of the findings related to STM characterization of surface reactions have appeared in earlier issues.6-9 The Perspective by Fourkas2 presents salient features of the physical chemistry and spectroscopy of nanofabrication. In order to meet the need for increasing transistor density in integrated circuits, one needs to develop lithography techniques that are economically viable. The resolution of optical lithographic techniques is usually limited by the wavelength of the excitation light. Absorbance modulation photolithography and two-color excitation/deactivation photolithography can overcome some of the limitations imposed by diffraction. Such nanolithographic techniques are useful also in growing secondary nanostructures.10 The development of new materials such as photochromic molecules with high extinction coefficients will play a dominant role in making the lithography a successful technique.
r 2010 American Chemical Society
Prashant V. Kamat Deputy Editor University of Notre Dame, Notre Dame, Indiana 46556
REFERENCES (1)
Ravishankar, N. Seeing Is Believing: Electron Microscopy for Investigating Nanostructures.J. Phys. Chem. Lett. 2010, 1, 1212-1220. (2) Fourkas, J. Nanoscale Photolithography with Visible Light. J. Phys. Chem. Lett. 2010, 1, 1221-1227. (3) Brandstetter, T.; Wagner, T.; Fritz, D. R.; Zeppenfeld, P. Tunable Ag Nanowires Grown on Cu(110)-Based Templates. J. Phys. Chem. Lett. 2010, 1, 1026–1029. (4) Kim, S. M.; Pint, C. L.; Amama, P. B.; Zakharov, D. N.; Hauge, R. H.; Maruyama, B.; Stach, E. A. Evolution in Catalyst Morphology Leads to Carbon Nanotube Growth Termination. J. Phys. Chem. Lett. 2010, 1, 918–922. (5) Nogami, M.; Koike, R.; Jalem, R.; Kawamura, G.; Yang, Y.; Sasaki, Y. Synthesis of Porous Single-Crystalline Platinum Nanocubes Composed of Nanoparticles. J. Phys. Chem. Lett. 2010, 1, 568–571. (6) Guo, S.; Kandel, S. A. Scanning Tunneling Microscopy of Mixed Valence Dinuclear Organometallic Cations and Counterions on Au(111). J. Phys. Chem. Lett. 2010, 1, 420–424. (7) Oh, J.; Kondo, T.; Hatake, D.; Iwasaki, Y.; Honma, Y.; Suda, Y.; Sekiba, D.; Kudo, H.; Nakamura, J. Significant Reduction in Adsorption Energy of CO on Platinum Clusters on Graphite. J. Phys. Chem. Lett. 2010, 1, 463–466. (8) Choi, J.; Lee, H.; Kim, K.-j.; Kim, B.; Kim, S. Chemical Doping of Epitaxial Graphene by Organic Free Radicals. J. Phys. Chem. Lett. 2010, 1, 505–509. (9) Franke, K. J.; Schulze, G.; Pascual, J. I. Excitation of JahnTeller Active Modes during Electron Transport through Single C60 Molecules on Metal Surfaces. J. Phys. Chem. Lett. 2010, 1, 500–504. (10) Hujdic, J. E.; Taggart, D. K.; Kung, S.-C.; Menke, E. J. Lead Selenide Nanowires Prepared by Lithographically Patterned Nanowire Electrodeposition. J. Phys. Chem. Lett. 2010, 1, 1055–1059. (11) Dvornikov, A. S.; Walker, E. P.; Rentzepis, P. M. Two-Photon Three-Dimensional Optical Storage Memory. J. Phys. Chem. A 2009, 113, 13633–13644. (12) Castleman, A. W.; Khanna, S. N. Clusters, Superatoms, and Building Blocks of New Materials. J. Phys. Chem. C 2009, 113, 2664–2675.
Received Date: March 18, 2010 Accepted Date: March 19, 2010 Published on Web Date: April 15, 2010
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DOI: 10.1021/jz1003582 |J. Phys. Chem. Lett. 2010, 1, 1283–1283
