Black TiO Films with Photothermal-Assisted Photocatalytic Activity Prepared by Reactive Sputtering.

Titanium oxide is widely applied as a photocatalyst. However, its low efficiency and narrow light absorption range are two main disadvantages that severely impede its practical application. In this work, black TiO films with different chemical compositions were fabricated by tuning target voltage and controlling O flow during reactive DC magnetron sputtering. The optimized TiO films with mixed phases (TiO, TiO, TiO, and TiO) exhibited fantastic photothermal and photocatalytic activity by combining high light-absorptive TiO and TiO phases with the photocatalytic TiO phase. The sample prepared with oxygen flow at 5.6 ± 0.2 sccm and target voltage near 400 V exhibited excellent optical absorbance of 89.29% under visible light, which could improve surface temperature to 114 °C under sunlight. This film could degrade Rhodamine-B up to 74% after 150 min of UV irradiation. In a word, this work provides a guideline for fabricating black TiO films with photothermal-assisted photocatalytic activity by reactive DC magnetron sputtering, which could avoid the usage of hydrogen and is convenient for quantity preparation.