Visualizing H2O molecules reacting at TiO2 active sites with transmission electron microscopy.
Wentao YuanBeien ZhuXiao-Yan LiThomas Willum HansenYang OuKe FangHangsheng YangZe ZhangJakob Birkedal WagnerYi GaoYong WangPublished in: Science (New York, N.Y.) (2020)
Imaging a reaction taking place at the molecular level could provide direct information for understanding the catalytic reaction mechanism. We used in situ environmental transmission electron microscopy and a nanocrystalline anatase titanium dioxide (001) surface with (1 × 4) reconstruction as a catalyst, which provided highly ordered four-coordinated titanium "active rows" to realize real-time monitoring of water molecules dissociating and reacting on the catalyst surface. The twin-protrusion configuration of adsorbed water was observed. During the water-gas shift reaction, dynamic changes in these structures were visualized on these active rows at the molecular level.