Atomic layer deposition-assisted growth of CuAl LDH on carbon fiber as a peroxidase mimic for colorimetric determination of H2O2 and glucose

Abstract

In this work, an atomic-layer-deposited Al₂O₃-induced LDH growth strategy was proposed to easily prepare carbon fiber-supported ultrathin CuAl LDH nanosheets (CF@CuAl-LDH). The uniform Al₂O₃ coating on carbon fiber (CF) was obtained using an atomic layer deposition (ALD) method and was used as a pinpoint inductive layer to transform into ultrathin CuAl LDH nanosheets through hydrothermal treatment. The LDH nanosheets grew densely attached to the CF surface and the nanosheet thickness was only about 3.3 nm. The obtained CF@CuAl-LDH exhibited superior enzyme mimic activity because its unique structural features offered a large ion-accessible surface, an increased active site area, and efficient electron-transfer pathways. Accordingly, a simple and sensitive biosensor was developed for colorimetric determination of H₂O₂ and glucose. The established method was successfully used to detect glucose in juice samples with satisfactory results.