Efficient suspension plasma spray fabrication of black titanium dioxide coatings with visible light absorption performances

The present study is a part of continuing research efforts devoted to modifying nano titania by tailoring its structure for enhanced photocatalytic performances. The study concerns suspension plasma spray fabrication of black titanium dioxide coatings with porous microstructures and high photocatalytic activity. The black titania showed composite structure comprising anatase, rutile, metastable brookite, and Ti 2 O 3 with markedly narrowed band gap of 2.71 eV. Further TEM characterization revealed that formation of the black titania was associated with grain growth and with tremendous lattice disorders, which are predominately responsible for visible light absorption. Examination of photocatalytic performances of the black titania coatings showed enhanced absorption and degradation of methylene blue under visible light, giving inspiring insights into surface coating construction of black titania for photocatalytic applications.