For what purpose do you want to use TiO2 coatings?

Among the two TiO2 crystalline phases, anatase and rutile that can contribute to the photocatalysis, it is generally assumed that the anatase—the metastable phase, which by thermal treatment irreversibly turns into rutile—allows a higher-photocatalytic degradation of the pollutants.

The following references can guide you to address the issue: https://link.springer.com/article/10.1007/s11666-014-0066-5

http://iopscience.iop.org/article/10.1088/1757-899X/114/1/012031/pdf

https://www.hindawi.com/journals/jnm/2008/384171/

The crystalline form of TiO2 plays no role for plasma spraying since the particles are melted anyway.

Dear Sharma,

Spherical particles/granules present better flowability, however particle size distribution and density of the particles are also important parameters.

Regards,

Fatih.