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Title: 2D‐Material‐Integrated Micromachines: Competing Propulsion Strategy and Enhanced Bacterial Disinfection
Abstract

2D transition‐metal‐dichalcogenide materials, such as molybdenum disulfide (MoS2) have received immense interest owing to their remarkable structure‐endowed electronic, catalytic, and mechanical properties for applications in optoelectronics, energy storage, and wearable devices. However, 2D materials have been rarely explored in the field of micro/nanomachines, motors, and robots. Here, MoS2 with anatase TiO2 is successfully integrated into an original one‐side‐open hollow micromachine, which demonstrates increased light absorption of TiO2‐based micromachines to the visible region and the first observed motion acceleration in response to ionic media. Both experimentation and theoretical analysis suggest the unique type‐II bandgap alignment of MoS2/TiO2 heterojunction that accounts for the observed unique locomotion owing to a competing propulsion mechanism. Furthermore, by leveraging the chemical properties of MoS2/TiO2, the micromachines achieve sunlight‐powered water disinfection with 99.999% Escherichia coli lysed in an hour. This research suggests abundant opportunities offered by 2D materials in the creation of a new class of micro/nanomachines and robots.

 
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Award ID(s):
1930649 1710922
NSF-PAR ID:
10441854
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
34
Issue:
30
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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