Journal
ACS NANO
Volume 10, Issue 1, Pages 1662-1670Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsnano.5b07420
Keywords
hydrogenation; MoO3; hydrogen bronzes; oxygen vacancies; transition metal oxides
Categories
Funding
- National Natural Science Foundation of China [11574119, 51290271, 11474364, 51202300, 51373205, 51402218]
- Guangdong Natural Science Funds for Distinguished Young Scholars [2014A030306017]
- Guangdong Natural Science Foundation [2014A030313381]
- Fundamental Research Funds for the Central Universities
Ask authors/readers for more resources
The hydrogenation process of the layered alpha-MoO3 crystal was investigated on a nanoscale. At low hydrogen concentration, the hydrogenation can lead to formation of HxMoO3 without breaking the MoO3 atomic flat surface. For hydrogenation with high hydrogen concentration, hydrogen atoms accumulated along the < 101 > direction on the MoO3, which induced the formation of oxygen vacancy line defects. The injected hydrogen atoms acted as electron donors to increase electrical conductivity of the MoO3. Near-field optical measurements indicated that both of the HxMoO3 and oxygen vacancies were responsible for the coloration of the hydrogenated MoO3, with the latter contributing dominantly. On the other hand, diffusion of hydrogen atoms from the surface into the body of the MoO3 will encounter a surface diffusion energy barrier, which was for the first time measured to be around 80 meV. The energy barrier also sets an upper limit for the amount of hydrogen atoms that can be bound locally inside the MoO3 via hydrogenation. We believe that our findings has provided a clear picture of the hydrogenation mechanisms in layered transition-metal oxides, which will be helpful for control of their optoelectronic properties via hydrogenation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available