Insight into the Contributions of Surface Oxygen Vacancies on the Promoted Photocatalytic Property of Nanoceria
Autor: | Zhiyao Chu, Fengyuan Liu, Yuan-Pei Lan, Xuewen Xia, Junqi Li, Chaoyi Chen, Junshan Zhang, Deyang Ning, Xisong Mao |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
Photoluminescence
Materials science Hydrogen Annealing (metallurgy) Band gap General Chemical Engineering chemistry.chemical_element 02 engineering and technology 010402 general chemistry 01 natural sciences surface oxygen vacancies photocatalytic property Article band gap photoinduced carriers General Materials Science Photodegradation QD1-999 Photocurrent 021001 nanoscience & nanotechnology nanoceria 0104 chemical sciences Chemistry Chemical engineering chemistry Photocatalysis Nanorod 0210 nano-technology |
Zdroj: | Nanomaterials, Vol 11, Iss 1168, p 1168 (2021) Nanomaterials Volume 11 Issue 5 |
ISSN: | 2079-4991 |
Popis: | Oxygen vacancies (OVs) have critical effects on the photoelectric characterizations and photocatalytic activity of nanoceria, but the contributions of surface OVs on the promoted photocatalytic properties are not clear yet. In this work, we synthesized ceria nanopolyhedron (P-CeO2), ceria nanocube (C-CeO2) and ceria nanorod (R-CeO2), respectively, and annealed them at 600 °C in air, 30%, 60% or pure H2. After annealing, the surface OVs concentration of ceria elevates with the rising of H2 concentration. Photocatalytic activity of annealed ceria is promoted with the increasing of surface OVs, the methylene blue photodegradation ratio with pure hydrogen annealed of P-CeO2, C-CeO2 or R-CeO2 is 93.82%, 85.15% and 90.09%, respectively. Band gap of annealed ceria expands first and then tends to narrow slightly with the rising of surface OVs, while the valence band (VB) and conductive band (CB) of annealed ceria changed slightly. Both of photoluminescence spectra and photocurrent results indicate that the separation efficiency of photoinduced electron-hole pairs is significantly enhanced with the increasing of the surface OVs concentration. The notable weakened recombination of photogenerated carrier is suggested to attribute a momentous contribution on the enhanced photocatalytic activity of ceria which contains surface OVs. |
Databáze: | OpenAIRE |
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