1 research outputs found
Embedding Metal in the Interface of a p‑n Heterojunction with a Stack Design for Superior Z‑Scheme Photocatalytic Hydrogen Evolution
The construction of a p-n heterojunction
is an efficient strategy to resolve the limited light absorption and
serious charge-carrier recombination in semiconductors and enhance
the photocatalytic activity. However, the promotion effect is greatly
limited by poor interfacial charge transfer efficiency as well as
reduced redox ability of charge carriers. In this work, we demonstrate
that the embedding of metal Pd into the interface between n-type C<sub>3</sub>N<sub>4</sub> and p-type Cu<sub>2</sub>O can further enhance
the interfacial charge transfer and increase the redox ability of
charge carriers through the design of the C<sub>3</sub>N<sub>4</sub>-Pd-Cu<sub>2</sub>O stack nanostructure. The embedded Pd nanocubes
in the stack structure not only trap the charge carriers from the
semiconductors in promoting the electron–hole separation but
also act as a Z-scheme “bridge” in keeping the strong
reduction/oxidation ability of the electrons/holes for surface reactions.
Furthermore, Pd nanocubes also increase the bonding strength between
the two semiconductors. Enabled by this unique design, the hydrogen
evolution achieved is dramatically higher than that of its counterpart
C<sub>3</sub>N<sub>4</sub>-Cu<sub>2</sub>O structure without Pd embedding.
The apparent quantum efficiency (AQE) is 0.9% at 420 nm for the designed
C<sub>3</sub>N<sub>4</sub>-Pd-Cu<sub>2</sub>O. This work highlights
the rational interfacial design of heterojunctions for enhanced photocatalytic
performance