A combination of a perovskite and polymer were mixed, then the mixture was heat treated at elevated temperature. Some undesired reactions led to the decomposition of perovskite phase. But, in the presence of a dopant this destruction did not occur. Can anyone lend their expertise on this?
Ebrahim;
Could you provide more information about:
What kind of dopant did you use, which reactions were precisely suppressed and what was the calcination temperature.
Dear Houshang
I think without dopant, perovskite structure almost decomposes to the secondary phases below 500°C, due to the interaction of thermal decomposition products of polymer with perovskite phase (i.e. reaction between carbon and components of perovskite). But in the presence of a dopant with larger ionic radii (substituted A site of perovskite), this phenomenon does not occurred
Could you please give me the formulation of the perovskite?
Does it also occur when you do not have carbon or polymer?
The perovskite phase is bismuth ferrite, which is very sensitive to small deviation from stoiciometric ratio. Without carbon (100% perovskite) undesired reaction does not happen. But in the presence of larger dopant substituted Bi3+ sites, the final structure is original provskite.
Ebrahim,
I had experienced something similar in the past when a Perovskite was decomposing easily in a reducing atmosphere. It happened at higher temperatures (+1000 C) and carbon was reacting with oxygen of the perovskite.
However, in your case, I'm afraid not to be very useful since I can't see why the large dopant would suppress such a reaction.
Sorry,
Regards,
In fact, your observation is not unexpected. Bi-containing perovskites are not very stable (probably, because of the same lone pair that gives them all these nice multiferroic properties). And partial substitution of Bi by other cations of comparable size is a popular way to increase their stability.
- Badges
- Science topic