Editorial pubs.acs.org/JPCL
Some Interesting Properties and Promising Applications of Nanostructured Materials
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dimensional material, high carrier mobility, the ambipolar field effect, and unusual in-plane anisotropy.21−25 Some future directions and challenges about this relatively new type of materials and their potential applications is also discussed. In summary, nanostructured materials have fascinating properties and many potential applications in technologies. While significant advancement has been made in the synthesis/ fabrication and characterization of nanomaterials, understanding of their fundamental properties is still not complete, particularly issues related to surface and interfaces, and their wide range of potential applications are only beginig to be exploited. Further research is needed in both the theoretical and experimental fronts in order to fully explore their interesting properties and functionalities for many important applications ranging from energy to electronics, environment, and medicine.
ompared to bulk or isolated atoms and molecules, nanostructured materials possess some unique physical and chemical properties due to quantum confinement effect and their extremely large surface-to-volume ratio. These unique properties often results in novel functionalities that are useful for technological applications, including electronics, photonics, catalysis, energy conversion and storage, sensing, imaging, drug delivery, and therapy. The quantum confinement effect allows the optical and electronic properties of nanostructures to be controlled by varying the size and shape. Their large surface area is useful for applications like catalysis and lend conveniently for surface engineering or functionalization desired for many purposes. Recent progress in synthesis and fabrication techniques have made it possible to generate highly sophisticated nanostructures with multiple and enhanced functionalities for a broad range of emerging applications, including solar energy conversion and CO2 reduction. In this issue, three Perspectives highlight some intriguing properties of nanostructured materials, including semiconductor quantum dots (QDs), graphene, and black phosphors as well as some examples of their potential applications. In the Perspective by Lifshitz,1 interesting properties of semiconductor colloidal quantum dots (CQDs) are discussed,2−4 with a focus on attempting to resolve some conflicts concerning the influence of immediate surroundings on their optical properties. It clarifies whether exciton recombination processes in CQDs are affected by the type of crystal−ligand bonding and if these excitonic processes experience direct coupling to the ligands’ vibrational modes.5−9 Several important issues are discussed, including surface−ligand bonding that introduces band gap electronic states and affects intraband and interband relaxation processes, crystal electronic states that are directly coupled to molecular vibrational states, and photoejected carriers from an Auger process or ionization processes that can diffuse temporarily onto a ligand site. In the Perspective by Low et al.,10 novel properties of graphene are highlighted with an emphasis on recent advances in their fabrication and applications in photocatalytic CO2 reduction for solar fuel production, an area that has attracted considerable attention due to its potential for addressing energy and global warming issues at the same time.11−13 Graphene exhibits unique properties including excellent electronic conductivity, good optical transmission, and high stability,14−16 which are well suited for CO2 reduction through photocatalysis.17−19 Some challenges involving graphene-based photocatalysts are also discussed, including the influence of defects, the photocorrosion, effect of graphene on reaction products, and the lack of a clear understanding of the chargetransport mechanism. In the Perspective by Castellanos-Gomez,20 a somewhat unusual 2D material, black phosphors, is reviewed, with a focus on its unique properties as compared to other 2D materials including graphene, including band gap values that span a wide spectral range not covered by any other isolated two© 2015 American Chemical Society
Jin Z. Zhang, Senior Editor
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University of California, Santa Cruz, California
AUTHOR INFORMATION
Notes
Views expressed in this Editorial are those of the author and not necessarily the views of the ACS.
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RELATED READINGS
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The Journal of Physical Chemistry Letters
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DOI: 10.1021/acs.jpclett.5b02209 J. Phys. Chem. Lett. 2015, 6, 4429−4430
