Silver-Modified Nanosized Ferroelectrics as a Novel Photocatalyst

Abstract

Monodispersed ferroelectric BaTiO3 nanoparticles are synthesized as a model system to investigate the effect of ferroelectricity on a photocatalytic process. The results demonstrate that ferroelectricity can directly affect the photocatalytic activity due to promotion of the separation of photo-excited carriers by spontaneous polarization in ferroelectric materials. Moreover, Ag nanoparticles are attached on these BaTiO3 to further improve the photocatalytic property.

Enhanced photocatalytic activity in Ag-nanoparticle-dispersed BaTiO3 composite thin films: Role of charge transfer

“…The Ag/BTO thin films with different Ag/(Ag+BTO) ratios (abbreviated as Ag x /BTO, x = 0, 5,10,15,20,25,30, where x is the mole percent (mol%) of Ag) were prepared by a sol-gel and spin-coating method starting with barium acetate (Ba(CH 3 COO) 2 /BTO films, the ultimate solution was spin-coated onto glass substrate with size of 2 cm × 2 cm at 500 rpm for 5 s and subsequently 3000 rpm for 15 s. Finally, the thin films were dried at 150 ℃ for 30 s and successively heated to 500 ℃ for 1 h. These sequences of coating and pyrolysis treatments were repeated for 10 times.…”

“…To determine the dispersion and size of the Ag NPs inside the films, TEM analysis was performed for the Ag 25 /BTO thin film as shown in Fig. 2.…”

“…1). The Ag NPs in the Ag 25 /BTO thin film have a wide range of size distribution from 20 to 110 nm with a mean size of ca. 52 nm as shown in distribution histogram ( Fig.…”

“…The appearance of Na peaks is due to the diffusion of Na atoms onto the surface from the glass substrate after annealing, the Si peak results from the SiO 2 substrate, and the carbon peak arises from an overlying contaminant hydrocarbon layer which is unavoidable for the XPS analysis. High-resolution XPS spectra of Ag 3d, Ba 3d, Ti 2p, and O 1s peaks of the Ag 25 /BTO thin film are displayed in Fig. 4.…”

“…For instance, Liu et al [24] prepared flower-like BTO nanotube arrays by a hydrothermal method, and concluded that the photocatalytic performance of BTO nanotube arrays can be improved by dispersing Ag NPs. A recent study on Ag-modified BTO NPs [25] has investigated the effects of the ferroelectricity and loading of Ag on the photocatalytic property of BTO, and demonstrated that the photocatalytic efficiency could be significantly enhanced by attaching Ag onto the surface of ferroelectric BTO. Despite of a few emerging published works, the detailed effect of CT between Ag NPs and BTO on the photocatalytic activity has not been addressed up to now.…”