Constructing conductive titanium carbide nanosheet (MXene) network on polyurethane/polyacrylonitrile fibre framework for flexible strain sensor

Zhixin Jia; Zhangjie Li; Shufei Ma; Wenqiang Zhang; Yongjun Chen; Yuanfang Luo; Demin Jia; Bangchao Zhong; Joselito M Razal; Xungai Wang; Lingxue Kong

doi:10.1016/j.jcis.2020.09.035

Constructing conductive titanium carbide nanosheet (MXene) network on polyurethane/polyacrylonitrile fibre framework for flexible strain sensor

J Colloid Interface Sci. 2021 Feb 15:584:1-10. doi: 10.1016/j.jcis.2020.09.035. Epub 2020 Sep 18.

Authors

Affiliations

¹ School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
² Chongqing Key Laboratory of Green Synthesis and Applications, College of Chemistry, Chongqing Normal University, Chongqing 401331, China.
³ Deakin University, Geelong, Institute for Frontier Materials, Waurn Ponds, Victoria 3216, Australia.

PMID: 33035798
DOI: 10.1016/j.jcis.2020.09.035

Abstract

Hypothesis: MXenes (two-dimensional early transition metal carbides and carbonitrides) possess both excellent conductivity and surface hydrophilicity, enabling more diverse potential applications. However, in flexible strain sensors, the flexible substrates are usually composed of hydrophobic elastomers such as thermoplastic polyurethane (TPU). To enhance the interactions between MXenes and hydrophobic. substrates, it is wiser to change the composition of the flexible substrate than to modify the surface of MXenes, so as to improve the interactions between the flexible substrate and MXenes without losing the excellent conductivity of MXene.

Experiments: We introduce polyacrylonitrile (PAN) into TPU, and then fabricate a flexible TPU/PAN mat through electrospinning. A highly conductive and stretchable Ti₃C₂ MXene/TPU/PAN mat was then prepared by a simple dip-coating process. The interaction mechanism between Ti₃C₂ MXene nanosheets and TPU/PAN mat was investigated by XPS and FT-IR. Finally, we build the MXene/TPU/PAN mat into a flexible strain sensor with excellent properties.

Findings: By introducing PAN into flexible substrate, the interaction between Ti₃C₂ MXene and the flexible substrate was effectively improved without compromising Ti₃C₂ MXene's excellent conductivity. The MXene/TPU/PAN strain sensor possesses a wide sensing range (0-80%), a fast response (<140.6 ms), a low limit of detection (<0.1%), splendid coating adhesion and excellent durability (>1750 cycles). All of these properties are demanded in wearable electronics.

Keywords: MXene; Polyacrylonitrile; Thermoplastic polyurethane.