Trifluoromethylative and Pentafluoroethylative Heterofunctionalization (C-O, C-S, and C-N) of Alkenes Using Visible Light Photocatalysis.

A mild and general method for photoredox-catalyzed trifluoromethylative and pentafluoroethylative heterofunctionalization of alkenes is proposed. In this reaction, the Togni reagent serves as a CF- or CFCF-radical source for the regioselective formation of the C-CF and C-CFCF bonds from alkenes, and additional nucleophiles (O, S, N) provide C-O, C-S, and C-N bonds, respectively. These reactions provide a common gateway to access the fluoroalkylative heterofunctionalization of alkenes.

Flexible Indium-Tin Oxide Crystal on Plastic Substrates Supported by Graphene Monolayer.

Flexible and crystallized indium-tin oxide (ITO) thin films were successfully obtained on plastic polyethylene terephthalate (PET) films with monolayered graphene as a platform. The highly crystalline ITO (c-ITO) was first fabricated on a rigid substrate of graphene on copper foil and it was subsequently transferred onto a PET substrate by a well-established technique. Despite the plasma damage during ITO deposition, the graphene layer effectively acted as a Cu-diffusion barrier.

Nano-Fenton Reactors as a New Class of Oxidative Stress Amplifying Anticancer Therapeutic Agents.

Cancer cells, compared to normal cells, are under oxidative stress associated with an elevated level of reactive oxygen species (ROS) and are more vulnerable to oxidative stress induced by ROS generating agents. Thus, manipulation of the ROS level provides a logical approach to kill cancer cells preferentially, without significant toxicity to normal cells, and great efforts have been dedicated to the development of strategies to induce cytotoxic oxidative stress for cancer treatment. Fenton reaction is an important biological reaction in which irons convert hydrogen peroxide (H2O2) to highly toxic hydroxyl radicals that escalate ROS stress.

High through-plane thermal conduction of graphene nanoflake filled polymer composites melt-processed in an L-shape kinked tube.

Design of materials to be heat-conductive in a preferred direction is a crucial issue for efficient heat dissipation in systems using stacked devices. Here, we demonstrate a facile route to fabricate polymer composites with directional thermal conduction. Our method is based on control of the orientation of fillers with anisotropic heat conduction.

The influence of high dielectric constant aluminum oxide sputter deposition on the structure and properties of multilayer epitaxial graphene.

High dielectric constant aluminum oxide (Al(2)O(3)) is frequently used as the gate oxide in high electron mobility transistors and the impact of its deposition by radio frequency (RF) magnetron sputtering on the structural and electrical properties of multilayer epitaxial graphene (MLG) grown by graphitization of silicon carbide (SiC) is reported. Micro-Raman spectroscopy and temperature dependent Hall mobility measurements reveal that the processing induced changes to the structural and electrical properties of the MLG can be minimal when the oxide deposition conditions are optimal. High-resolution transmission electron microscopy (HRTEM) analysis confirms that the Al(2)O(3)/MLG interface is relatively sharp and that our thickness approximation of the MLG using angle resolved x-ray photoelectron spectroscopy (ARXPS) is accurate.