http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Local Atomic and Electronic Structure of Boron Chemical Doping in Monolayer Graphene
Zhao, Liuyan,Levendorf, Mark,Goncher, Scott,Schiros, Theanne,Pá,lová,, Lucia,Zabet-Khosousi, Amir,Rim, Kwang Taeg,Gutié,rrez, Christopher,Nordlund, Dennis,Jaye, Cherno,Hybertsen, Mar American Chemical Society 2013 Nano letters Vol.13 No.10
<P>We use scanning tunneling microscopy and X-ray spectroscopy to characterize the atomic and electronic structure of boron-doped and nitrogen-doped graphene created by chemical vapor deposition on copper substrates. Microscopic measurements show that boron, like nitrogen, incorporates into the carbon lattice primarily in the graphitic form and contributes ∼0.5 carriers into the graphene sheet per dopant. Density functional theory calculations indicate that boron dopants interact strongly with the underlying copper substrate while nitrogen dopants do not. The local bonding differences between graphitic boron and nitrogen dopants lead to large scale differences in dopant distribution. The distribution of dopants is observed to be completely random in the case of boron, while nitrogen displays strong sublattice clustering. Structurally, nitrogen-doped graphene is relatively defect-free while boron-doped graphene films show a large number of Stone-Wales defects. These defects create local electronic resonances and cause electronic scattering, but do not electronically dope the graphene film.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2013/nalefd.2013.13.issue-10/nl401781d/production/images/medium/nl-2013-01781d_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl401781d'>ACS Electronic Supporting Info</A></P>
Large scale metal-free synthesis of graphene on sapphire and transfer-free device fabrication
Song, Hyun Jae,Son, Minhyeok,Park, Chibeom,Lim, Hyunseob,Levendorf, Mark P.,Tsen, Adam W.,Park, Jiwoong,Choi, Hee Cheul The Royal Society of Chemistry 2012 Nanoscale Vol.4 No.10
<P>Metal catalyst-free growth of large scale single layer graphene film on a sapphire substrate by a chemical vapor deposition (CVD) process at 950 °C is demonstrated. A top-gated graphene field effect transistor (FET) device is successfully fabricated without any transfer process. The detailed growth process is investigated by the atomic force microscopy (AFM) studies.</P>
Atomistic Interrogation of B–N Co-dopant Structures and Their Electronic Effects in Graphene
Schiros, Theanne,Nordlund, Dennis,Palova, Lucia,Zhao, Liuyan,Levendorf, Mark,Jaye, Cherno,Reichman, David,Park, Jiwoong,Hybertsen, Mark,Pasupathy, Abhay American Chemical Society 2016 ACS NANO Vol.10 No.7
<P>Chemical doping has been demonstrated to be an effective method for producing high-quality, large-area graphene with controlled carrier concentrations and an atomically tailored work function. The emergent optoelectronic properties and surface reactivity of carbon nanostructures are dictated by the microstructure of atomic dopants. Co-doping of graphene with boron and nitrogen offers the possibility to further tune the electronic properties of graphene at the atomic level, potentially creating p- and n-type domains in a single carbon sheet, opening a gap between valence and conduction bands in the 2-D semimetal. Using a suite of high-resolution synchrotron-based X-ray techniques, scanning tunneling microscopy, and density functional theory based computation we visualize and characterize B–N dopant bond structures and their electronic effects at the atomic level in single-layer graphene grown on a copper substrate. We find there is a thermodynamic driving force for B and N atoms to cluster into BNC structures in graphene, rather than randomly distribute into isolated B and N graphitic dopants, although under the present growth conditions, kinetics limit segregation of large B–N domains. We observe that the doping effect of these BNC structures, which open a small band gap in graphene, follows the B:N ratio (B > N, p-type; B < N, n-type; BN, neutral). We attribute this to the comparable electron-withdrawing and -donating effects, respectively, of individual graphitic B and N dopants, although local electrostatics also play a role in the work function change.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2016/ancac3.2016.10.issue-7/acsnano.6b01318/production/images/medium/nn-2016-01318z_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn6b01318'>ACS Electronic Supporting Info</A></P>
Polycrystalline Graphene with Single Crystalline Electronic Structure
Brown, Lola,Lochocki, Edward B.,Avila, José,Kim, Cheol-Joo,Ogawa, Yui,Havener, Robin W.,Kim, Dong-Ki,Monkman, Eric J.,Shai, Daniel E.,Wei, Haofei I.,Levendorf, Mark P.,Asensio, Marí,a,Shen American Chemical Society 2014 NANO LETTERS Vol.14 No.10
<P>We report the scalable growth of aligned graphene and hexagonal boron nitride on commercial copper foils, where each film originates from multiple nucleations yet exhibits a single orientation. Thorough characterization of our graphene reveals uniform crystallographic and electronic structures on length scales ranging from nanometers to tens of centimeters. As we demonstrate with artificial twisted graphene bilayers, these inexpensive and versatile films are ideal building blocks for large-scale layered heterostructures with angle-tunable optoelectronic properties.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2014/nalefd.2014.14.issue-10/nl502445j/production/images/medium/nl-2014-02445j_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl502445j'>ACS Electronic Supporting Info</A></P>