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Franklin Kim

Bio: Franklin Kim is an academic researcher from ShanghaiTech University. The author has contributed to research in topics: Graphene & Nanorod. The author has an hindex of 36, co-authored 51 publications receiving 22925 citations. Previous affiliations of Franklin Kim include University of California, Berkeley & Kyoto University.


Papers
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Journal ArticleDOI
21 Jul 2009-ACS Nano
TL;DR: A morphological engineering approach for gold nanoparticles is reported by constructing an evolutionary tree consisting of a few branches of independent growth pathways that yields a string of evolving, continuously tunable morphologies from one reaction, collectively producing a library of nanoparticles with minimal changes of reaction parameters.
Abstract: In addition to chemical composition, the chemistry of nanocrystals involves an extra structural factor—morphology—since many of their properties are size- and shape-dependent. Although often described as artificial atoms or molecules, the morphological control of nanoparticles has not advanced to a level comparable to organic total synthesis, where complex molecular structures can be rationally designed and prepared through stepwise reactions. Here we report a morphological engineering approach for gold nanoparticles by constructing an evolutionary tree consisting of a few branches of independent growth pathways. Each branch yields a string of evolving, continuously tunable morphologies from one reaction, therefore collectively producing a library of nanoparticles with minimal changes of reaction parameters. In addition, the tree also provides ground rules for designing new morphologies through crossing over different pathways.

108 citations

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TL;DR: In this article, single-crystalline nanoribbons were used as substrates for the epitaxial growth of different functional thin films deposited by laser ablation techniques.
Abstract: Single-crystalline nanoribbons were used as substrates for the epitaxial growth of different functional thin films deposited by laser ablation techniques. This simple method yields highly crystalline bilayer nanotapes with sharp structural and compositional interfaces. As an example, Co0.05Ti0.95O2@SnO2 nanotapes are shown to be ferromagnetic at room temperature. These composite nanotapes, with their various possible functionalities, represent an important new class of nanoscale building blocks for optoelectronic applications.

97 citations

Journal ArticleDOI
TL;DR: In this article, a method to self-assemble PCP crystals into two-dimensional monolayers using Langmuir-Blodgettry is presented. But this method is not suitable for high dimensional polymers.
Abstract: Porous coordination polymers (PCPs), with their ordered nanoporous systems and large surface areas, are very attractive for numerous applications that involve controlled molecular transport properties. To fully exploit their potential, a straightforward processing method to deposit the PCP crystals on various substrates and to create freestanding membranes with a controlled pore orientation is highly desirable. Here, we report a strategy to self-assemble PCP crystals into two-dimensional monolayers using Langmuir–Blodgettry. This approach allows the deposition on various substrates over several square centimeters, uniformly and with controllable density of the crystals. In addition we show that by controlling the morphology of the crystalline building blocks we can program their orientation on the substrates. Using a copper grid as the substrate, these assemblies can also be fabricated as freestanding sheets. This approach represents a very simple and scalable processing method to translate the orientation of the channel network from the individual crystal to the macroscopic scale, and can help to incorporate this interesting class of materials within advanced hierarchical systems.

71 citations

Journal ArticleDOI
TL;DR: In this article, post thermal treatments were performed by heating the water phase in a water bath at 60 C for an hour with magnetic stirring, then the precipitates were filtered and washed with absolute alcohol and distilled water, then dried in vacuum at 20 C.
Abstract: CdCl2 or ZnCl2. The jars were sealed and kept static at room temperature in the dark for up to 7 days. Then the precipitates were filtered and washed with absolute alcohol and distilled water, then dried in vacuum at 20 C. After extracting the organic phase, post thermal treatments were performed by heating the water phase in a water bath at 60 C for an hour with magnetic stirring. X-ray powder diffraction (XRD) measurements of the as-prepared sample were carried on a Rigaku D/max-cA X-ray diffractometer with Cu Ka radiation (k = 1.54178 Š). The TEM images and ED pattern were taken on a Hitachi H800 transmission electron microscope with an accelerating voltage of 200 kV. HRTEM images were taken on a JEOL-2010 transmission electron microscope.

59 citations

Journal ArticleDOI
13 Nov 2012-ACS Nano
TL;DR: This report demonstrates how a complexation process could be utilized for directing the self-assembly of nanosheets by confining the nanosheet-polyelectrolyte complexation at air-liquid or liquid-liquid interfaces, and successfully assembled into various mesoscale architectures including fibers, capsules, and films.
Abstract: Significant progress has been made during the past decade in preparing nanosheets from a wide range of materials, which are actively pursued for various applications such as energy storage, catalysis, sensing, and membranes. One of the next critical challenges is developing a robust and versatile assembly method which allows construction of the nanosheets into functional structures tailored for each specific purpose. An interesting characteristic of nanosheets is that they often behave as charged macromolecules and thus can readily interact with an oppositely charged polyelectrolyte to form a stable complex. In this report, we demonstrate how such a complexation process could be utilized for directing the self-assembly of nanosheets. By confining the nanosheet–polyelectrolyte complexation at air–liquid or liquid–liquid interfaces, the nanosheets are successfully assembled into various mesoscale architectures including fibers, capsules, and films. Furthermore, incorporation of additional components such as...

44 citations


Cited by
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Journal ArticleDOI
TL;DR: An overview of the synthesis, properties, and applications of graphene and related materials (primarily, graphite oxide and its colloidal suspensions and materials made from them), from a materials science perspective.
Abstract: There is intense interest in graphene in fields such as physics, chemistry, and materials science, among others. Interest in graphene's exceptional physical properties, chemical tunability, and potential for applications has generated thousands of publications and an accelerating pace of research, making review of such research timely. Here is an overview of the synthesis, properties, and applications of graphene and related materials (primarily, graphite oxide and its colloidal suspensions and materials made from them), from a materials science perspective.

8,919 citations

Journal ArticleDOI
TL;DR: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties are equally important.
Abstract: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

6,852 citations