About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Ceramics for Clean Hydrogen
|
| Presentation Title |
Structure Sensitivity of Photochemical Reactions on AgNbO3 |
| Author(s) |
Sipei Li, Paul Salvador, Gregory Rohrer |
| On-Site Speaker (Planned) |
Sipei Li |
| Abstract Scope |
AgNbO3 is a potential catalyst for the photochemical production of hydrogen from water. One characteristic that distinguishes it from similar metal oxide water splitting catalysts is its potential to absorb visible light. We have studied the photochemical reactivity of many differently orientated crystals at the surface of a AgNbO3 ceramic. Reactive sites on each grain are identified by SEM and AFM imaging of photo reduced silver that forms when the sample is illuminated while immersed in a silver bearing aqueous solution. While the photo deposition of silver is sensitive to surface preparation, for samples annealed at high temperature after polishing, reduced silver deposits are strongly correlated with features of the microstructure. For example, silver is preferentially reduced on {100} surfaces compared to other orientations and forms preferentially forms on certain ferroelectric domains. These observations can be used to optimize catalyst particle shape for water-splitting. |