Preparation of Pt@SnO2 Core‐Shell Nanoparticles for Photocatalytic Degradation of Formaldehyde

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.