Motion-based phenol detection and degradation using 3D hierarchical AA-NiMn-CLDHs@HNTs-Ag nanomotors

Abstract

Dual-functional micro/nanomotors that can sensitively detect and rapidly degrade organic pollutants show great application prospects in the field of environmental remediation. Here we demonstrate the first proof-of-concept of a novel self-propelled nanomachine for simultaneous colorimetric detection and removal of aquatic pollutants based on the use of ascorbic acid-functionalized NiMn-CLDHs@HNTs-Ag (AA-NiMn-CLDHs@HNTs-Ag) nanomotors. The as-prepared nanomotors were assembled from NiMn-CLDH nanosheets with intrinsic oxidase/peroxidase-like activity and HNTs, revealing a unique 3D hierarchical architecture with more accessible reactive sites. Ag NPs were introduced into the lumen of halloysite nanotubes (HNTs) and acted as a catalyst for the decomposition of H₂O₂ to produce O₂ bubbles for the propulsion of nanomotors. Benefitting from the autonomous movement, 3D hierarchical morphology and robust peroxidase-like activity, AA-NiMn-CLDHs@HNTs could achieve selective and sensitive detection of phenol with a limit of detection of 0.225 μM as well as quick degradation of phenol via a Fenton-like reaction. This study provides a promising strategy for the synthesis of micro/nanomotors for simultaneous detection and removal of organic pollutants from aqueous samples.