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Research


Silks are natural polymers with outstanding properties. Some spider silks are tougher than the toughest synthetic polymers and even outperform steel in terms of strength by weight.

We believe that these outstanding properties are due to the interesting structure of silk, featuring a peculiar organization down to molecular scales. Our imaging techniques provide unprecedented insights into the organization at single-molecule resolutions.

This knowledge will be used to develop new processes to make silks artificially: novel materials that are environmentally completely benign and feature excellent mechanical properties.


We embed nanoparticles into polymers in order to give these plastics new functionality. We currently focus on functionalized graphenes as nanofillers, with an emphasis on developing materials with excellent mechanical properties [10]. However, graphene can also be used to make rubber electrically conductive [14].

We developed several new techniques to directly measure the mechanical interaction strength between graphene particles and different polymers [15], [17]. This allows us to systematically develop new materials with improved strength and stiffness.

The described experimental techniques are enabling tools which we use for a new approach to nanocomposite development: away from the "trial & error" philosophy, and toward a systematic design of materials with predictable properties.


Graphene is the strongest and toughest material known to man, and it has outstanding electronic properties. Hannes Schniepp has been active in the graphene field since 2005. Some of his early publications in the field on chemically prepared functionalized graphene have since become citation classics [4], [7], [8], [10]. His graphene works have been cited 4910 times.

Currently, the research team investigates opportunities to exploit the outstanding electronic properties of graphene oxide for future optoelectronic applications, such as photovoltaics (funded by NSF).

We exploit the excellent mechanical properties of functionalized graphenes for nanocomposite applications.


We are interested in interfacial forces at the solid–liquid interface as they govern many processes in various fields reaching from biomedical applications to petroleum engineering.

Interfacial forces at the solid–solid interface are important in composite and nanocomposite materials, where the strength of these interactions is crucial for the mechanical performance of the materials systems.

We directly probe interfacial interactions at the nanoscale using scanning probe techniques.


In the nanoworld, systems can be designed to self-organize into ordered structures. For engineering purposes, this phenomenon can be exploited to produce tiniest structures or for self-healing materials [5].

We currently investigate molecular-scale self-assembly using liquid-cell atomic force microscopy (AFM) [3], [5], [6], [9], [11], [12], [17] for sensing applications and to reveal the structural secrets of silk, a complex, biological material.

Prof. Schniepp has a long-standing expertise in self-assembly of surfactant molecules at the solid—liquid interface [3], [5], [6], [9], [11], [12], [17]. Surfactants often make micelle-like structures the on surface with feature size of just a few nanometers. These structures can be visualized using liquid-cell AFM, which is an excellent tool to study them. Surfactants are crucial in many applications, such as detergency, oil recovery, and corrosion inhibition [12]; they are also a self-healing model system [5].


A common problem in implants (hip implants, teeth) is that the attachment between the bone and the implant is imperfect. Ultimately, this leads to losening of the implant, which requires additional surgery.

Our team is investigating novel surface treatments of implant materials, which facilitate successful integration. This work is carried out incollaboration with Dr. Daniel E. MacDonald (PI) from the Hospital for Special Surgery in New York City, ranked several times as the #1 orthopedic hospital in the Unites States.


Our Related Publications

[26] Small (2014) — Cui, Oyer, Glover, Schniepp & Adamson
"Large Scale Thermal Exfoliation and Functionalization of Boron Nitride"
[25] Adv. Materials (2013) — Schniepp*, Koebley & Vollrath
"Brown Recluse Spider's Nanometer Scale Ribbons of Stiff Extensible Silk"
[24] Int. J. Oral Maxillofac. Implants (2012) — Rapuano, Hackshaw, Schniepp & MacDonald
"Effects of Coating a Titanium Alloy with Fibronectin on the Expression of Osteoblast Gene Markers in the MC3T3 Osteoprogenitor Cell Line"
Cited 6 times
[23] J. Mater. Chem. (2012) — Cai, Thorpe, Adamson & Schniepp*
"Methods of Graphite Exfoliation"
Cited 37 times
[22] J. Phys. Chem. C (2012) — Glover, Adamson & Schniepp*
"Charge-Driven Selective Adsorption of Sodium Dodecyl Sulfate on Graphene Oxide Visualized by Atomic Force Microscopy"
Cited 6 times
[21] Nano LIFE (2012) — Li, Schniepp, Aksay & Car
"Phonon-Induced Anisotropic Dispersion Forces On A Metallic Substrate"
[20] J. Am. Chem. Soc. (2012) — Oyer, Carrillo, Hire, Schniepp, Asandei, Dobrynin & Adamson
"Stabilization of Graphene Sheets by a Structured Benzene/Hexafluorobenzene Mixed Solvent"
Cited 19 times
[19] Biomacromolecules (2012) — Greving, Cai, Vollrath & Schniepp*
"Shear-Induced Self-Assembly of Native Silk Proteins into Fibrils Studied by Atomic Force Microscopy"
Cited 23 times
[18] Macromolecules (2011) — Glover, Cai, Overbeek, Kranbuehl & Schniepp*
"In Situ Reduction of Graphene Oxide in Polymers"
Cited 22 times
[17] J. Appl. Polym. Sci. B (2011) — Kranbuehl, Cai, Glover & Schniepp*
"Measurement of the interfacial attraction between graphene oxide sheets and the polymer in a nanocomposite"
Cited 7 times
[16] Coll. Surf. B (2011) — MacDonald, Rapuano & Schniepp
"Surface oxide net charge of a titanium alloy: Comparison between effects of treatment with heat or radiofrequency plasma glow discharge"
Cited 12 times
[15] AIP Conf. Proc. (2010) — Cai, Glover, Wallin, Kranbuehl & Schniepp*
"Direct Measurement of the Interfacial Attractions between Functionalized Graphene and Polymers in Nanocomposites"
Cited 3 times
[14] Appl. Opt. (2010) — Fang, Punckt, Leung, Schniepp & Aksay
"Tuning of structural color using a dielectric actuator and multifunctional compliant electrodes"
Cited 11 times
[13] ACS Nano (2008) — Schniepp, Kudin, Li, Car & Aksay
"Bending Properties of Single Functionalized Graphene Sheets Probed by Atomic Force Microscopy"
Cover Story.   Cited 80 times
[12] Langmuir (2008) — Murira, Punckt, Schniepp, Khusid, & Aksay
"Inhibition and Promotion of Copper Corrosion by CTAB in a Microreactor System"
Cited 11 times
[11] J. Phys. Chem C (2008) — Schniepp, Shum, Saville & Aksay
"Orientational Order of Molecular Assemblies on Rough Surfaces"
Cited 13 times
Orientational Order
[10] Nature Nanotechnol. (2008) — Ramanathan, Abdala, Stankovich, Dikin, Herrera-Alonso, Piner, Adamson, Schniepp, Chen, Ruoff, Nguyen, Aksay, Prud'homme & Brinson
"Functionalized graphene sheets for polymer nanocomposites."
Cited 1097 times
Raman
[9] Langmuir (2008) — Schniepp, Saville & Aksay
"Tip-Induced Orientational Order of Surfactant Micelles on Gold."
Cited 5 times
Tip-induce order
[8] Nano Letters (2008) — Kudin, Ozbas, Schniepp, Prud’homme, Aksay & Car
"Raman spectra of graphite oxide and functionalized graphene sheets"
Cited 1001 times
Raman
[7] Chem. Mater. (2007) — McAllister, Li, Adamson, Schniepp, Abdala, Liu, Herrera-Alonso, Milius, Car, Prud’homme & Aksay
"Single Sheet Functionalized Graphene by Oxidation and Thermal Expansion of Graphite"
Cover story.   Cited 1237 times
ChemMater
[6] J. Phys. Chem. B (2007) — Schniepp, Shum, Saville & Aksay
"Surfactant Aggregates at Rough Solid–Liquid Interfaces"
Cited 15 times
SDS/Gold
[5] J. Am. Chem. Soc. (2006) — Schniepp, Saville & Aksay
"Self-Healing of Surfactant Surface Micelles on Millisecond Time Scales"
Cited 20 times
Featured in Nature Materials (October 2006).
Fast Surfactant Dynamics
[4] J. Phys. Chem. B (2006) — Schniepp, Li, McAllister, Sai, Herrera-Alonso, Adamson, Prud’homme, Car, Saville & Aksay
"Functionalized Single Graphene Sheets Derived from Splitting Graphite Oxide"
Cited 1390 times
Functionalized Graphene
[3] Phys. Rev. Lett. (2006) — Saville, Chun, Li, Schniepp, Car & Aksay
"Orientational Order of Molecular Assemblies on Inorganic Crystals"
Cited 14 times
CTAC on HOPG


Previous Research Projects

Nanomaterials: 
  • Bulk Production of Exfoliated Functionalized Graphene [6], [7], [8]
Self-Assembly:
  • Orientational Order of Self-Assembly on Molecular and Colloidal Length Scales  [3], [5], [6], [9], [11], [12], [17]
  • Millisecond Self-Healing of Protective Surfactant Surface Layers  [5]
  • Imaging Surfactant Surface Aggregates on Rough Surfaces  [6], [11]
  • Tip-Induced Orientational Order of Surfactant Surface Micelles  [9]
Scanning Probe + Optical Microscopy: 
  • Development of a Microscope Integrating Scanning Probe and Confocal Fluorescene Approaches
Biophysics: 
  • Scanning Probe Investigation of Native Nuclear Membranes in Suspended State
  • Conformation of DNA 
Nanophotonics: 
  • Experimental Study of Spontaneous Emission in Nanoparticles  [1]
  • Shape- and Size-Dependence of Spontaneous Emission from Nanoparticles  [2]