Photocatalytic acetaldehyde oxidation in air using spacious TiO2 films prepared by atomic layer deposition on supported carbonaceous sacrificial templates

TL;DR

This study develops spacious TiO2 photocatalytic films using atomic layer deposition on carbon templates, demonstrating enhanced degradation of indoor air pollutants like acetaldehyde.

Contribution

It introduces a novel method for creating high-surface-area TiO2 films with improved photocatalytic activity through templated ALD and calcination.

Findings

TiO2 films showed excellent photocatalytic activity for acetaldehyde degradation

Optimized films outperformed commercial reference films

The morphology and performance depend on template type and ALD cycles

Abstract

Supported carbon nanosheets and carbon nanotubes served as sacrificial templates for preparing spacious TiO2 photocatalytic thin films. Amorphous TiO2 was deposited conformally on the carbonaceous template material by atomic layer deposition (ALD). Upon calcination at 550{\deg}C, the carbon template was oxidatively removed and the as-deposited continuous amorphous TiO2 layers transformed into interlinked anatase nanoparticles with an overall morphology commensurate to the original template structure. The effect of type of template, number of ALD cycles and gas residence time of pollutant on the photocatalytic activity, as well as the stability of the photocatalytic performance of these thin films was investigated. The TiO2 films exhibited excellent photocatalytic activity towards photocatalytic degradation of acetaldehyde in air as a model reaction for photocatalytic indoor air pollution abatement. Optimized films outperformed a reference film of commercial PC500.