Preparation of Pt@SnO2 core-shell nanoparticles for photocatalytic degradation of formaldehyde

Abstract

We report the synthesis and characterization of platinum-tin oxide core-shell nanoparticles (Pt@SnO2) for use as a photocatalyst for formaldehyde (HCHO) degradation. We used a sol-gel process followed by calcination to prepare the Pt@SnO2 photocatalyst. Transmission Electron Microscopy (TEM) revealed that the average Pt core diameter was 7-10 nm in diameter, and the SnO2 shell was approximately 2 nm thick. UV-Visible spectroscopy displayed the peak from the Pt@SnO2 core-shell structures is red-shifted by 16 nm from that of the Pt nanoparticles. We determined photocatalytic activity by irradiating formaldehyde gas in the presence of nanoparticle samples with an 18 W daylight lamp for 180 min. The irradiated Pt@SnO2 nanoparticles achieved 93.2% formaldehyde degradation, while TiO2 (P25), SnO2, and 1 wt.% Pt/SnO2 achieved 70.1%, 67.5%, and 66.0% respectively. Thus, Pt@SnO2 was the most effective material for the degradation of formaldehyde, demonstrating its potential for use as a high efficiency photocatalyst for the degradation of formaldehyde. We prepared a novel nanocomposite Pt@SnO2 materials as a photocatalyst, the average Pt core diameter was 7-10 nm in diameter, and the SnO2 shell was approximately 2 nm thick. Pt@SnO2 exhibited the greatest formaldehyde degradation efficiency of 93.2% during 18 W daylight illumination at room temperature. Copyright © 2014 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany.