Fractional photo-current dependence of graphene quantum dots prepared from carbon nanotubes.
Phys Chem Chem Phys
; 17(38): 24566-9, 2015 Oct 14.
Article
em En
| MEDLINE
| ID: mdl-26351706
ABSTRACT
We report on the photo-conductivity studies of chemically synthesized graphene quantum dots (GQDs) of average size 12 nm obtained by the oxidative acid treatment of MWCNTs. The dependence of photocurrent Iph (Iph = Iill - Idark) on the laser intensity P under a wide range of laser intensities (5 mW ≤ P ≤ 60 mW) shows a fractional power dependence of Iph on light intensity. The temperature dependence (300 K < T < 50 K) of Iph observed in thin films of these GQDs indicates that in the higher temperature region (T > â¼100 K), as the temperature increases, the number of thermally generated carriers increase resulting in increased Iph. At sufficiently low temperatures (T ≤ 100 K), a constant Iph is observed, indicating a constant photo-carrier density. Such a behavior is typically observed in many photoactive disordered semiconductors, which are often used in a variety of applications. We believe that the investigations presented here will enhance our understanding of the photocurrent generation phenomenon in chemically obtained GQDs.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Phys Chem Chem Phys
Assunto da revista:
BIOFISICA
/
QUIMICA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Índia