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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 over 1697 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 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. 
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. 
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. 
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.
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© 2007–2011 Dr. Hannes C. Schniepp. All Rights Reserved.