Visible-light photocatalysis and charge carrier dynamics of elemental crystalline red phosphorus.
J Chem Phys
; 153(2): 024707, 2020 Jul 14.
Article
em En
| MEDLINE
| ID: mdl-32668923
ABSTRACT
Elemental red phosphorus (red P) is a new class of photocatalysts with a desirable bandgap of â¼1.7 eV and has a strong visible-light response. Here, we show that the efficiency of red P is limited by severe electron trapping at deep traps that are intrinsic to the different crystal facets of the red P. To overcome this, we synthesized the red P/RGO (reduced graphene oxide) composite in a one-step ampoule chemical vapor deposition synthesis that formed a conducive interface between the red P photocatalyst and the RGO acceptor for efficient interfacial charge transport. As substantiated through photoelectrochemical characterization and ultrafast (femtoseconds) transient absorption spectroscopy, the interfacing with RGO provided a rapid pathway for the photocharges in red P to be interfacially separated, thereby circumventing the slower the charge trapping process. As a result, up to a sevenfold increase in the photocatalytic hydrogen production rate (apparent quantum yield = 3.1% at 650 nm) was obtained for the red P/RGO relative to the pristine red P.
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Base de dados:
MEDLINE
Idioma:
En
Revista:
J Chem Phys
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China