Fabrication and characterization of well-dispersed plasmonic Pt nanoparticles on Ga-doped ZnO nanopagodas array with enhanced photocatalytic activity

• Atomic layer deposited Pt NPs are well-dispersed, uniform, and much better than conventional methods.
• Pt/GZO hybrid nanocomposites can improve photocatalytic activity significantly.
• Pt NPs with suitable size act as plasmonic centres transferring hot electrons and electromagnetic energies.
• There are competing effects between Pt NPs and GZO for photocatalytic activity.
• An optimal Pt NPs loading content exhibits best photocatalytic activity.

Pt/GZO hybrid nanocomposites were formed by depositing Pt nanoparticles (NPs) using an atomic layer deposition (ALD) technique onto one-dimensional (1D) Ga-doped ZnO (GZO) nanopagodas (NPGs). The GZO NPGs were prepared by metal–organic chemical vapor deposition (MOCVD). The ALD deposited Pt NPs were well-dispersed and uniform on the surfaces of the GZO NPGs, which were much better than Pt NPs prepared by conventional wet chemistry methods. Pt/GZO hybrid nanocomposites with 30 ALD cycles exhibited significant improvement in photocatalytic activity by about 2.7 times higher than GZO NPGs under 254 nm UV illuminations. The effect of Pt NPs on photocatalytic activities of Pt/GZO hybrid nanocomposites was discussed using various photocatalytic mechanisms. Due to the competing effects of decorated Pt NPs on absorbance/transmittance, electron–hole separation/recombination, and the local surface plasmon resonance, there exists an optimal Pt NPs loading content, which exhibits a maximal photocatalytic activity of 1D Pt/GZO hybrid nanocomposites.

A schematic diagram contains reactions participating in photocatalysis processes with energy band arrangement of an individual Pt NP/GZO NPG hybrid nanocomposite.Figure optionsDownload as PowerPoint slide