Growth of monolayer, bi-layer, and tri-layer single-crystalline graphene (SCG) using chemical vapor deposition method is reported. SCG's mechanical properties and single-crystalline nature were characterized and verified by atomic force microscope and Raman spectroscopy. Electro-mechanical switches based on mono-and bi-layer SCG were fabricated, and the superb properties of SCG enable the switches to operate at pull-in voltage as low as 1 V, and high switching speed about 100 ns. These devices exhibit lifetime without a breakdown of over 5000 cycles, far more durable than any other graphene nanoelectromechanical system switches reported. V C 2014 AIP Publishing LLC. [http://dx.

Combination of shrink induced nano-composites technique and layer-by-layer (LbL) self-assembled graphene challenges controlling surface morphology. Adjusting shrink temperature achieves tunability on graphene surface morphology on shape memory polymers, and it promises to be an alternative in fields of highsurface-area conductors and molecular detection. In this study, self-assembled graphene on a shrink polymer substrate exhibits nanowrinkles after heating. Induced nanowrinkles on graphene with different shrink temperature shows distinct surface roughness and wettability. As a result, it becomes more hydrophilic with higher shrink temperatures. The tunable wettability promises to be utilized in, for example, microfluidic devices. The graphene on shrink polymer also exhibits capability of being used in sensing applications for pH and alphafetoprotein (AFP) detection with advantages of label free and low cost, due to self-assembly technique, easy functionalization, and antigen-antibody reaction on graphene surface. The detection limit of AFP detection is down to 1 pg/mL, and therefore the sensor also has a significant potential for biosensing as it relies on low-cost self-assembly and label-free assay.

Properties of phosphorene are intensively researched by many research groups since it was discovered in 2014. This new 2D material has a direct band-gap, depending on the number of layers (0.3 eV for bulk to 2.0 eV for monolayer) similar to MoS2. In this paper, we report layer-by-layer (LbL) deposition method to deposit a few layers of phosphorene film on the substrate, and successfully fabricate phosphorene field effect transistor (FET) with LbL black phosphorus (BP) film. By using the FET characteristics of the device, we fabricate biosensors with Poly-L-lysine (PLL) linker molecules and Alpha-fetoprotein (AFP) antibody to detect different concentration of AFP antigen (0.1 ppb to 1 ppm). The results indicate that BP can be a promising material for biosensing applications.

Self-assembled graphene by layer-by-layer (LbL) self-assembly on a shrink polymer substrate demonstrates nano wrinkles after heating. As a result, graphene with nano wrinkles shows different wettability and surface roughness, depending on shrink temperatures. The graphene on shrink polymer performs sensing applications for pH and alpha-fetoprotein (AFP) detection with advantages of low cost and label free, due to self-assembly technique, ease of modification, and antigen-antibody surface reaction.

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