Combining Cocatalyst and Oxygen Vacancy to Synergistically Improve Fe<sub>2</sub>O<sub>3</sub> Photoelectrochemical Water Oxidation Performance
Considering the poor conductivity of Fe<sub>2</sub>O<sub>3</sub> and the weak oxygen evolution reaction associated with it, surface hole accumulation leads to electron hole pair recombination, which inhibits the photoelectrochemical (PEC) performance of the Fe<sub>2<...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-01-01
|
| Series: | Crystals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4352/15/1/85 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Considering the poor conductivity of Fe<sub>2</sub>O<sub>3</sub> and the weak oxygen evolution reaction associated with it, surface hole accumulation leads to electron hole pair recombination, which inhibits the photoelectrochemical (PEC) performance of the Fe<sub>2</sub>O<sub>3</sub> photoanode. Therefore, the key to improving the PEC water oxidation performance of the Fe<sub>2</sub>O<sub>3</sub> photoanode is to take measures to improve the conductivity of Fe<sub>2</sub>O<sub>3</sub> and accelerate the reaction kinetics of surface oxidation. In this work, the PEC performances of Fe<sub>2</sub>O<sub>3</sub> photoanodes are synergistically improved by combining loaded an FeOOH cocatalyst and oxygen vacancy doping. Firstly, amorphous FeOOH layers are successfully prepared on Fe<sub>2</sub>O<sub>3</sub> nanostructures through simple photoassisted electrodepositon. Then oxygen vacancies are introduced into FeOOH-Fe<sub>2</sub>O<sub>3</sub> through plasma vacuum treatment, which reduces the content of Fe-O (O<sub>L</sub>) and Fe-OH (-OH), jointly promoting the generation of oxygen vacancies. Oxygen vacancy can increase the concentration of most carriers in Fe<sub>2</sub>O<sub>3</sub> and form photo-induced charge traps, promoting the separation of electron holes and enhancing the conductivity of Fe<sub>2</sub>O<sub>3</sub>. The other parts of -OH act as oxygen evolution catalysts to reduce the reaction obstacle of water oxidation and promote the transfer of holes to the electrode/electrolyte interface. The performance of FeOOH-Fe<sub>2</sub>O<sub>3</sub> after plasma vacuum treatment has been greatly improved, and the photocurrent density is about 1.9 times higher than that of the Fe<sub>2</sub>O<sub>3</sub> photoanode. The improvement in the water oxidation performance of PEC is considered to be the synergistic effect of the cocatalyst and oxygen vacancy. All outstanding PEC response characteristics show that the modification of the cocatalyst and oxygen vacancy doping represent a favorable strategy for synergistically improving Fe<sub>2</sub>O<sub>3</sub> photoanode performance. |
|---|---|
| ISSN: | 2073-4352 |