Effective Cocatalyst Pt/PtO Nanodots on La₂O₃ Microspheres for Degradation of Methyl Orange.

Platinum (Pt) has been intensively studied as an effective cocatalyst for photocatalysis, but most reports have focused on metallic Pt rather than PtO. Here, Pt/PtO nanodots were deposited on porous yolk-shell La₂O₃ microspheres. XRD patterns and XPS analysis demonstrated the coexistence of Pt and PtO, which was beneficial for photocatalytic performance. SEM images showed the yolk-shell structure of La₂O₃, and TEM images demonstrated that the Pt/PtO nanodots were uniformly distributed on the La₂O₃ microspheres. The rate constant of the hybrid was calculated to be 0.00656 min for methyl orange (MO) degradation, while that of bare La₂O₃ was only 0.00303 min. This work suggests that the use of the deposited cocatalyst Pt/PtO on La₂O₃ microspheres is a promising strategy for the degradation of organic pollutants.