Enhanced Thermoelectric Conversion Efficiency of CVD Graphene with Reduced Grain Sizes.

The grain size of CVD (Chemical Vapor Deposition) graphene was controlled by changing the precursor gas flow rates, operation temperature, and chamber pressure. Graphene of average grain sizes of 4.1 µm, 2.

In-Plane Thermal Conductivity of Polycrystalline Chemical Vapor Deposition Graphene with Controlled Grain Sizes.

Manipulation of the chemical vapor deposition graphene synthesis conditions, such as operating P, T, heating/cooling time intervals, and precursor gas concentration ratios (CH/H), allowed for synthesis of polycrystalline single-layered graphene with controlled grain sizes. The graphene samples were then suspended on 8 μm diameter patterned holes on a silicon-nitride (SiN) substrate, and the in-plane thermal conductivities k(T) for 320 K < T < 510 K were measured to be 2660-1230, 1890-1020, and 680-340 W/m·K for average grain sizes of 4.1, 2.

How to reliably determine the complex refractive index (RI) of graphene by using two independent measurement constraints.

Reliable determination of the complex refractive index (RI) of graphene inherently requires two independent measurement realizations for two independent unknowns of the real (nG) and imaginary (kG) components, i.e., RI = nG + i kG.