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The Electronic Thermal Conductivity of Graphene
Kim, Tae Yun,Park, Cheol-Hwan,Marzari, Nicola American Chemical Society 2016 Nano letters Vol.16 No.4
<P>Graphene, as a semimetal with the largest known thermal conductivity, is an ideal system to study the interplay between electronic and lattice contributions to thermal transport. While the total electrical and thermal conductivity have been extensively investigated, a detailed first-principles study of its electronic thermal conductivity is still missing. Here, we first characterize the electron phonon intrinsic contribution to the electronic thermal resistivity of graphene as a function of doping using electronic and phonon dispersions and electron phonon couplings calculated from first principles at the level of density-functional theory and many-body perturbation theory (GW). Then, we include extrinsic electron impurity scattering using low-temperature experimental estimates. Under these conditions, we find that the in-plane electronic thermal conductivity ice of doped graphene is 300 W/mK at room temperature, independently of doping. This result is much larger than expected and comparable to the total thermal conductivity of typical metals, contributing 40% to the total thermal conductivity of bulk graphene. Notably, in samples whose physical or domain sizes are of the order of few micrometers or smaller, the relative contribution coming from the electronic thermal conductivity is more important than in the bulk limit, because lattice thermal conductivity is much more sensitive to sample or grain size at these scales. Last, when electron-impurity scattering effects are included we find that the electronic thermal conductivity is reduced by 30 to 70%. We also find that the Wiedemann Franz law is broadly satisfied at low and high temperatures but with the largest deviations of 20-50% around room temperature.</P>
Electron–Phonon Interactions and the Intrinsic Electrical Resistivity of Graphene
Park, Cheol-Hwan,Bonini, Nicola,Sohier, Thibault,Samsonidze, Georgy,Kozinsky, Boris,Calandra, Matteo,Mauri, Francesco,Marzari, Nicola American Chemical Society 2014 NANO LETTERS Vol.14 No.3
<P>We present a first-principles study of the temperature- and density-dependent intrinsic electrical resistivity of graphene. We use density-functional theory and density-functional perturbation theory together with very accurate Wannier interpolations to compute all electronic and vibrational properties and electron–phonon coupling matrix elements; the phonon-limited resistivity is then calculated within a Boltzmann-transport approach. An effective tight-binding model, validated against first-principles results, is also used to study the role of electron–electron interactions at the level of many-body perturbation theory. The results found are in excellent agreement with recent experimental data on graphene samples at high carrier densities and elucidate the role of the different phonon modes in limiting electron mobility. Moreover, we find that the resistivity arising from scattering with transverse acoustic phonons is 2.5 times higher than that from longitudinal acoustic phonons. Last, high-energy, optical, and zone-boundary phonons contribute as much as acoustic phonons to the intrinsic electrical resistivity even at room temperature and become dominant at higher temperatures.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2014/nalefd.2014.14.issue-3/nl402696q/production/images/medium/nl-2013-02696q_0006.gif'></P>
The 2019 materials by design roadmap
Alberi, Kirstin,Nardelli, Marco Buongiorno,Zakutayev, Andriy,Mitas, Lubos,Curtarolo, Stefano,Jain, Anubhav,Fornari, Marco,Marzari, Nicola,Takeuchi, Ichiro,Green, Martin L,Kanatzidis, Mercouri,Toney, M IOP 2019 Journal of Physics. D, Applied Physics Vol.52 No.1
<P>Advances in renewable and sustainable energy technologies critically depend on our ability to design and realize materials with optimal properties. Materials discovery and design efforts ideally involve close coupling between materials prediction, synthesis and characterization. The increased use of computational tools, the generation of materials databases, and advances in experimental methods have substantially accelerated these activities. It is therefore an opportune time to consider future prospects for materials by design approaches. The purpose of this Roadmap is to present an overview of the current state of computational materials prediction, synthesis and characterization approaches, materials design needs for various technologies, and future challenges and opportunities that must be addressed. The various perspectives cover topics on computational techniques, validation, materials databases, materials informatics, high-throughput combinatorial methods, advanced characterization approaches, and materials design issues in thermoelectrics, photovoltaics, solid state lighting, catalysts, batteries, metal alloys, complex oxides and transparent conducting materials. It is our hope that this Roadmap will guide researchers and funding agencies in identifying new prospects for materials design.</P>
Avila Neto Roberto Costa,de Souza Pablo Mazzuco,Rubert Jaine,Seibt Tiago André,Thomasi Rosana Marzari,Melo Adriano Arrué,Alves Marcelo Plada,da Rosa Ulguim André 한국작물학회 2023 Journal of crop science and biotechnology Vol.26 No.2
Herbicides belonging to the chemical group imidazolinones and the quinclorac herbicide are important to control weeds in fooded rice. The objective of this research was to evaluate the interaction of imidazolinones with quinclorac to control Cyperus iria resistant to acetolactate synthase inhibitors (ALS). It was conducted two experiments in a greenhouse in a completely randomized design with four replications. Colby’s methodology was used for experiment 1, through the application of quinclorac isolated and in mixture with herbicides imazethapyr, imazapyr e imazapic. The experiment 2, using dose–response curves, tested the herbicides quinclorac isolated and in diferent mixtures with the herbicide imazethapyr. For experiment 1, the expected and observed averages were compared. For experiment 2, the results were analyzed using the sigmoidal logistic model. Additive is the main interaction of mixtures of quinclorac with diferent herbicides from the chemical group of imidazolinones to control resistant C. iria. Mixing with imazethapyr at diferent proportions can cause an additive efect with quinclorac at higher doses.