Atomic Layer Deposition-Based Synthesis of Photoactive TiO2 Nanoparticle Chains by Using Carbon Nanotubes as Sacrificial Templates

TL;DR

This paper reports a novel method using atomic layer deposition and carbon nanotubes as templates to synthesize highly ordered TiO2 nanoparticle chains with high surface area, exhibiting excellent photocatalytic activity under UV light.

Contribution

It introduces a new synthesis approach combining ALD and sacrificial templates to create ordered TiO2 nanoparticle chains with enhanced photocatalytic properties.

Findings

Produced TiO2 nanoparticle chains with ~12 nm diameter.

Achieved ultrahigh surface area of 137 cm2 per cm2 of substrate.

Demonstrated high photocatalytic activity in degrading acetaldehyde.

Abstract

Highly ordered and self supported anatase TiO2 nanoparticle chains were fabricated by calcining conformally TiO2 coated multi-walled carbon nanotubes (MWCNTs). During annealing, the thin tubular TiO2 coating that was deposited onto the MWCNTs by atomic layer deposition (ALD) was transformed into chains of TiO2 nanoparticles (~12 nm diameter) with an ultrahigh surface area (137 cm2 per cm2 of substrate), while at the same time the carbon from the MWCNTs was removed. Photocatalytic tests on the degradation of acetaldehyde proved that these forests of TiO2 nanoparticle chains are highly photo active under UV light because of their well crystallized anatase phase.