Construction of Highly Active and Selective PolydopamineModified Hollow ZnO/Co 3 O 4 p‑n HeterojunctionCatalyst for Photocatalytic CO 2 Reduction
2020
The
facile synthesis of low-cost, eco-friendly photocatalysts with
high charge separation efficiency and CO2 adsorption capacity
for efficient photocatalytic CO2 reduction remains a challenge.
Herein, a hollow structured p-n heterojunction catalyst, polydopamine
(PDA)-ZnO/Co3O4, was successfully synthesized
by pyrolyzing bimetallic ZnCo-ZIFs, followed by modification with
PDA. Through optimizing the Zn/Co ratio, a high separation efficiency
of the photogenerated electron–hole pairs has been achieved.
Furthermore, by tuning the content of PDA on the surface of ZnO/Co3O4, the adsorption capacity of CO2 can
be maximized. Consequently, PDA15/ZnO/Co3O4 showed a CO production rate of 537.5 μmol/g/h with
a CO selectivity of 97.7% without using the photosensitizer and additional
sacrificial agent. Band structure based on results of X-ray photoelectron
spectroscopy, photoelectrochemical characterization, as well as density
functional theory calculation was used to propose a plausible mechanism
for photocatalytic CO2 reduction on the PDA15/ZnO/Co3O4. The present study provides an effective
approach to fabricate highly efficient photocatalysts based on semiconducting
metal oxides for CO2 reduction with remarkable abilities
of absorbing lights, separating charge carriers, and adsorbing CO2.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
67
References
21
Citations
NaN
KQI