A Simple Approach to MXene Micropatterning from Molecularly Driven Assembly

Linh Chi T Cao; Chao-An Jong; Shu-Han Hsu; Shih-Feng Tseng

doi:10.1021/acsomega.1c06662

A Simple Approach to MXene Micropatterning from Molecularly Driven Assembly

ACS Omega. 2021 Dec 16;6(51):35866-35875. doi: 10.1021/acsomega.1c06662. eCollection 2021 Dec 28.

Authors

Linh Chi T Cao¹, Chao-An Jong², Shu-Han Hsu¹, Shih-Feng Tseng³

Affiliations

¹ Sirindhorn International Institute of Technology, Thammasat University, Khlong Nueng, Pathum Thani 12120, Thailand.
² National Applied Research Laboratories, Taiwan Semiconductor Research Institute, Hsinchu 300091, Taiwan.
³ Department of Mechanical Engineering, National Taipei University of Technology, Taipei 106344, Taiwan.

Abstract

Here, a micropatterning strategy is demonstrated to achieve stable and selective MXene adsorption through the molecularly driven assembly. MXene flakes were assembled by strong interaction with a silicon substrate, which was functionalized by microcontact printing (μCP) to create an active surface. A clear micropattern was observed by scanning electron microscopy showing uniform coverage of MXene flakes. Atomic force microscopy revealed a pattern thickness of around 50 nm, much thinner than the patterns obtained by direct μCP. The obtained micropattern presents good stability against rinsing and sonication. X-ray photoelectron spectroscopy shows that this stability can be attributed to strong covalent bonding between MXene and active molecules on a silicon substrate. The sheet resistance of the as-formed MXene layer was measured at around 154.67 (Ω/□), which is lower than those of other published techniques with a similar thickness of around 50 nm. This method can achieve a well-defined MXene pattern around the sub-100 μm scale without requiring prior MXene surface modification. Therefore, MXene can retain its intrinsic surface property, allowing further molecule adsorption as a sensing platform. Moreover, this patterning technique does not require complicated control of ink preparation and offers possible application on a substrate of any geometry with few layers of thickness.