Particularly crystalline semiconductors with definite energy band gap
are required in developing various electronic devices.
The chemical structure of the CPEs provide a unique set of properties, including water solubility and processability, main-chain-controlled exciton and charge transport, variable band gap
light absorption and fluorescence, ionic interactions, and aggregation phenomena .
"In addition, by simply modifying the width of the graphene strips between the pores (the number of carbon atoms), this band gap
can be controlled.
It can be seen from Figure 6 that the GaN FE and DBE emissions exhibit obvious red shift with increasing temperature, indicating the reduction of the band gap
of GaN layer.
In this section, dependence of the band gap
(BG) of the infinitely thick ML-UR on the host dielectric material [[epsilon].sub.r] is presented.
Diffuse reflectance spectroscopy (DRS) spectra were acquired on a PerkinElmer Lambda 35 spectrophotometer with an integration sphere with a resolution of [+ or -]1nm; from the reflectance spectra, the Kubelka-Munk function was determined and the band gap
energy was estimated [12, 13].
Depth profiles from SIMS and AES were used to compare the compositional distributions and to determine the band gap
in the CIGS solar cells.
Moewes, "Band gap
engineering of graphene oxide by chemical modification," Carbon, vol.
It has band gap
of 1.53 eV that match to optimal spectra (1.39eV) and large absorption coefficient [alpha]=1x105 cm-1.
It is shown that, the occurrence of vacancies induces an increase of density of high-energy occupied states and the band gap
modification is obtained.
The cadmium zinc sulfide (CdZnS) thin film is one of the promising materials which is used as a wide band gap
(larger than 2.5 eV) window material in hetrojunction solar cells and in photoconductive devices.
On the other hand, electronic properties of h-BN layers are considerably different from those of graphene; graphene is a gapless material with metallic conduction , and the h-BN atomic layers possess a wide band gap