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    Group Photo after Todd Day's Thesis Defense

    T.Day, S.Aro, D.Keefer, S.Juhl, T.Fitzgibbons, J.Badding, J.Bischoff, J.Song, R.Ahn, M.Coco.; X.Li, Y.Liu, A.Leone, Y.Cheng, P.Ray; Missing: S.Chaudhuri

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    Polytwistane Nanothread Crystal

    View down thread axis of hexagonal crystal of nanothreads that exfoliates into thread bundles. JACS, v. 139, p.16343 (2017)

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    Carbon Nanothread Crystals

    Carbon nanothread crystals form from benzene: JACS, v. 139, p.16343 (2017)

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    Nickel Metalattices

    Nickel Metalattices by confined chemical vapor deposition. Nano Letters DOI:10.1021/acs.nanolett.7b04633

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    Silicon Small Core Single Crystal Optical Fiber

    Single-Crystal Silicon Optical Fiber by Direct Laser Crystallization. ACS Photonics v. 4, p. 85 (2017)

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    HPCVD of Hydrogenated Amorphous Silicon Films and Solar Cells

    HPCVD may allow for deposition over square km of rolled up substrate. Advanced Materials v. 28, p. 5939 (2016)

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    Tracing Pathways to Carbon Nanothreads

    Evaluating pathways that lead from benzene stacks to completely saturated carbon nanothreads. JACS v. 137, p. 14373 (2015)

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    Carbon Nanothreads from Benzene

    Benzene reacts to form "flexible diamond" nanothreads: Nature Materials, v. 14, p. 43 (2015)

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    Photovoltaic silicon p-i-n Junction Fibers

    1 m long silicon p-i-n junctions and 10 m long silicon layers: Advanced Materials, v.25, p.1461 (2013)

Research Overview

General Theme

The sp3 bonding of carbon nanothreads, combined with their synthesis through organic solid-state chemistry from benzene arguably makes them ‘hybrids’ that collectively function as both hydrocarbon molecules and nanomaterials.
A unifying theme in the Badding group's research is the use of pressure to synthesize, deposit, or probe solid state materials. We are interested in materials that have unusual micro or nano structure or chemical/physical behavior and often apply them to problems of significant technological interest. Photonic materials, energy materials for photovoltaics, and carbon nanomaterials have recently been of particular interest. In the Efree DOE Energy Frontier Research Center we have recently synthesized single crystals of carbon nanothreads (see rotating image above left and nanothread crystal sliding panel above; black spheres are carbons, light pink spheres are hydrogens) through a non-topochemical reaction from solid benzene. These "flexible diamond" nanothreads are sp3-bonded and one-dimensional and thus occupy a distinct position in a matrix of hybridization (sp2/sp3) and dimensionality (0D/1D/2D/3D) for carbon nanomaterials. From the point of view of polymers, nanothreads are very rigid, but from the point of view of bulk solids, they are highly flexible: unique mechanical properties can be anticipated. Much as graphite exfoliates into graphene, nanothread crystals exfoliate into thread bundles along their van der Waals separations. Fully saturated degree-6 nanothreads could exhibit a unique combination of strength, flexibility, and resilience, while partially saturated degree-4 threads with their stiff backbones may form a new class of organic conductors. The sp3 bonding of carbon nanothreads, combined with their synthesis through organic solid-state chemistry from benzene arguably makes them ‘hybrids’ that collectively function as both hydrocarbon molecules and nanomaterials. A new and growing sub-field of chemistry, physics, and materials science has been nucleated; see the Nanothread Bibliography. In IRG3 of the Penn State NSF Materials Research Science and Engineering Center, we have synthesized by high pressure chemical vapor deposition metalattices that are quantum confined yet interconnected to permit the flow of electrons and phonons and magnetic exchange. Single crystal silicon and germanium optical fibers and infrared fiber lasers (in the Air Force Center for Guided Wave Infrared Sources) synthesized by high pressure chemical vapor deposition are another recent focus.

About 1,000,000 kg per year of diamond is produced by high pressure methods, a much larger quantity than is produced by chemical vapor deposition.

Pressure is a thermodynamic variable that is as fundamental as temperature, but is underutilized in materials chemistry research. It can, for example, control interatomic distance (without much variation in other quantities such as the entropy), tune reaction chemical kinetics and thermodynamics (often over a much wider range than is possible with temperature), allow for solvents with hybrid liquid-like and gas-like properties, and infiltrate molecules and materials into near atomic scale voids. Superior materials properties or interesting behavior not possible without the use of pressure for chemical synthesis or tuning can thus be obtained. At the micro and nano scales, high pressure chemistry becomes much more straightforward and practical because pressure is force per unit area and the forces involved become very small as the area decreases. We use a wide range of pressure from just above atmospheric (0.1 megapascals) to tens of gigapascals. Pressure is practical for industrial scale synthesis and is indeed used by industry much more than by academic scientists. About 1,000,000 kg of diamond per year is produced at modest cost at pressures of 5 to 6 GPa, a much larger quantity than is produced by chemical vapor deposition.


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We thank the National Science Foundation (DMR-1431408), the Defense Advanced Research Projects Agency (PULSE and Extended Solids Projects), the Carnegie Institution of Washington EFREE DOE Energy Frontier Research Centers, the Air Force (Center of Excellence in Infrared Optical Materials), and the Penn State MRSEC, funded by National Science Foundation DMR-1420620 for current support.


Yunzhi Liu

Yunzhi Liu's new Nickel Metalattices Paper

Yunzhi Liu's new paper in Nano Letters describes synthesis of nickel metalattices. Magnetic measurements suggest that these nickel metalattices behave as interconnected yet magnetically confined nanoscale systems rather than as isolated nanoscale superparamagnetic systems coupled solely by dipolar interactions.

Sub Chaudhuri

Three New Students Join the Badding Group

New student Sikai Wu (USTC China) will be joining present students Xiang Li (Nanjing University) and Daniel Koeplinger (Delaware) on the nanothreads project. New students Nabila Nova (University of Dhaka, Bangladesh) and Andrew Glaid will be joining all the students in MRSEC IRG3, including group members Yan Cheng, Yunzhi Liu, and Brianna Laubacker.

Steve Aro

Steve Aro's New Job

Congratulations to Steve Aro on his new job at the PPG Coatings Innovation Center in Allison Park, PA.

Jesse Bischoff

Jesse Bischof's New Job

Congratulations to Jesse Bischoff on his new job at Silcotek, a company that, like us, performs plasma-free deposition of hydrogenated amorphous silicon.

Paramita Ray's New Job

Congratulations to Paramita Ray, who has finished her thesis defense and is now leaving for at job at Intel


Tom Fitzgibbons New Job

Congratulations to Tom Fitzgibbons on defending his thesis and his new job at Dow, where he will be joining recent group graduate Justin Sparks. Tom's work will continue to use synchrotron and neutron sources for characterization of complex materials.