Chemically Engineered Titanium Oxide Interconnecting Layer for Multijunction Polymer Solar Cells.

We report chemically tunable n-type titanium oxides using ethanolamine as a nitrogen dopant source. As the amount of ethanolamine added to the titanium oxide precursor during synthesis increases, the Fermi level of the resulting titanium oxides (ethanolamine-incorporated titanium oxides) significantly changes from -4.9 eV to -4.

Highly Water-Dispersible Graphene Nanosheets From Electrochemical Exfoliation of Graphite.

The electrochemical exfoliation of graphite has been considered to be an effective approach for the mass production of high-quality graphene due to its easy, simple, and eco-friendly synthetic features. However, water dispersion of graphene produced in the electrochemical exfoliation method has also been a challenging issue because of the hydrophobic properties of the resulting graphene. In this study, we report the electrochemical exfoliation method of producing water-dispersible graphene that importantly contains the relatively low oxygen content of <10% without any assistant dispersing agents.

All-printed nanomembrane wireless bioelectronics using a biocompatible solderable graphene for multimodal human-machine interfaces.

Recent advances in nanomaterials and nano-microfabrication have enabled the development of flexible wearable electronics. However, existing manufacturing methods still rely on a multi-step, error-prone complex process that requires a costly cleanroom facility. Here, we report a new class of additive nanomanufacturing of functional materials that enables a wireless, multilayered, seamlessly interconnected, and flexible hybrid electronic system.

Study on the origin of amorphous carbon peaks on graphene films synthesized on nickel catalysts.

We present our investigation results on the origin of the morphological defects on graphene films synthesized by chemical vapor deposition method on nickel catalytic substrates. These defects are small-base-area (SBA) peaks with tens of nanometer heights, and they diminish the applicability of graphene films. From atomic force microscopy observations on the graphene films prepared in various ways, we found that significant portion of the SBA peaks is formed in the crevices on the nickel substrates.

CO2-activated, hierarchical trimodal porous graphene frameworks for ultrahigh and ultrafast capacitive behavior.

Herein, we demonstrate CO2-activated macroscopic graphene architectures with trimodal pore systems that consist of 3D inter-networked macroporosity arising from self-assembly, mesoporosity arising from the intervoids of nanosheets, and microporosity via CO2 activation. The existence of micropores residing in hierarchical structures of trimodal porous graphene frameworks (tGFs) contributes to greatly improve the surface area and pore volume, which are ∼3.8 times greater than typical values of existing 3D macroporous graphene monoliths.

Confining grains of textured Cu2O films to single-crystal nanowires and resultant change in resistive switching characteristics.

By confining columnar grains of textured oxide film using anodized aluminum oxide template, we could obtain a grain-boundary-free (GB-free) cuprous oxide (Cu(2)O) nanowire arrays with a narrow diameter distribution and a high density under the same electrochemical deposition condition. A two-terminal device fabricated using an individual GB-free nanowire and Au/Cr electrodes exhibits bipolar resistive switching contrary to the unipolar one of a textured film, and Schottky-like conduction. On the other hand, a nanowire device with Pt electrodes reveals non-switching behavior and Ohmic conduction.