posted on 2017-01-19, 00:00authored byXiuqin Wu, Cheng Zhu, Liping Wang, Sijie Guo, Yalin Zhang, Hao Li, Hui Huang, Yang Liu, Junwang Tang, Zhenhui Kang
Overall
photocatalytic water splitting can proceed through a four-electron
or two-electron/two-step pathway. However, it is challenging to manipulate
the two- or four-electron pathway. Here, we present a carbon-based
nanostructure codoped with nitrogen, sulfur, and a transition metal
that exhibits reliable photocatalytic ability and satisfactory photostability
in water splitting without the need for sacrificial agents. Note that
in the present system the transition-metal-doped structure (M = Cr,
Cd, Fe, Zn) as a photocatalyst splits water into H2 and
O2 through a two-electron pathway while the structure on
doping with rare-earth (Re) elements (M = Re = Sm, Ce, Eu, Pr, Er)
acts as a photocatalyst via a four-electron pathway and carbon dots
work herein as an electron acceptor and a reduction cocatalyst.