nanoporous graphene which is used as nanosorbent was synthesized by chemical vapor deposition method via porous zinc oxide nanocatalyst. the reaction was carried out using methane as the carbon source and hydrogen as the carrier gas in a ratio of 4:1 at the temperature ranging 900-1050°c for 2-50 min. the product was characterized by scanning electron microscopy, transmission electron microscop...

Despite several years of research into graphene electronics, sufficient on/off current ratio I(on)/I(off) in graphene transistors with conventional device structures has been impossible to obtain. We report on a three-terminal active device, a graphene variable-barrier "barristor" (GB), in which the key is an atomically sharp interface between graphene and hydrogenated silicon. Large modulation...

Plenty of new two-dimensional materials including graphyne, graphdiyne, graphone, and graphane have been proposed and unveiled after the discovery of the "wonder material" graphene. Graphyne and graphdiyne are two-dimensional carbon allotropes of graphene with honeycomb structures. Graphone and graphane are hydrogenated derivatives of graphene. The advanced and unique properties of these new ma...

Graphene, 2D atomic-layer of sp2 carbon, has attracted a great deal of interest for use in solar cells, LEDs, electronic skin, touchscreens, energy storage devices, and microelectronics. This is due to excellent properties of graphene, such as a high theoretical surface area, electrical conductivity, and mechanical strength. The fundamental structure of graphene is also manipulatable, allowing ...

The design and optimization of 3D graphene nanostructures are critically important since the properties of electrochemical energy storages such as supercapacitors can be dramatically enhanced by tunable porous channels. In this work, we have developed porous graphene aerogels from graphene suspensions obtained via electrochemical exfoliation and explored their application as supercapacitor elec...

Ultra-light porous networks based on nano-carbon materials (such as graphene or carbon nanotubes) have attracted increasing interest owing to their applications in wide fields from bioengineering to electrochemical devices. However, it is often difficult to translate the properties of nanomaterials to bulk three-dimensional networks with a control of their mechanical properties. In this work, w...

Understanding and controlling of excited carrier dynamics is of fundamental and practical importance, particularly in photochemistry and solar energy applications. However, theory of energy relaxation of excited carriers is still in its early stage. Here, using ab initio molecular dynamics (MD) coupled with time-dependent density functional theory, we show a coverage-dependent energy transfer o...

This work presents a new class of porous graphene particles with a three-dimensional microscale network and an ultrahigh specific surface area (2590 m(2) g(-1)), which is obtained by the KOH activation of a compact graphene hydrogel. As supercapacitor electrodes, such porous graphene particles show high compressibility and little capacitance loss when subjected to a compressive force up to 40 M...

We report the experimental evidence for the formation of multi-quantum dots in a hydrogenated single-layer graphene flake. The existence of multi-quantum dots is supported by the low-temperature measurements on a field effect transistor structure device. The resulting Coulomb blockade diamonds shown in the color scale plot together with the number of Coulomb peaks exhibit the characteristics of...

Graphene, a two-dimensional carbon sheet, has attracted great interest due to its unique properties. To explore its practical applications, large-scale synthesis with controllable integration of individual graphene sheets is essential. To date, numerous approaches have been developed for graphene synthesis, including mechanical cleavage, epitaxial growth, and chemical vapor deposition. All of t...