Physico-Chemical nanomaterials science

Raman spectroscopy for monitoring strain of silver nanowires on flexible substrate
Wu W.1, Lin C.1, Qiu Y.1 Babichuk I.S.1,2, Yang J.1
1 Faculty of Intelligent Manufacturing, Wuyi University, 529020, Jiangmen, P.R. China. E-mail: wu_wenjin@163.com, ivan@szu.edu.cn
2 V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 03680, Kyiv, Ukraine.

The developments of portable electrical devices have increased the demand for flexible sensors, for example artificial skin. Electrodes with high surface conductivity, high transmittance in the visible wavelength range, and mechanical compliance are one of the major challenges in the fabrication of stretchable optoelectronic devices. According to the sensing mechanisms, flexible sensors mainly include transistor, capacitive, piezoelectric and piezoresistive sensors [1].
Silver nanowires (AgNWs) have widespread concern due to their excellent electrical and mechanical properties. The latter makes it possible to use them during strain. The resistance-strain effect refers to the change in electrical resistance of materials when it is deformed.
In this study, we used the drop cast method to achieve the natural and random distribution of AgNWs without destroying the length them on flexible substrate for created flexible conductive films. The initial research was to prepare a flexible substrate. We used different proportions of light curing liquids, cured by UV lamp, and selected suitable substrate films according to viscosity, hardness and surface smoothness.
Afterwards, this flexible film was covered AgNWs through a stencil to give a controlled shape and allowed to dry at room temperature. The flexible conductive film in detail was characterized by means of microscopy, spectroscopy and electrical measurements. The morphological and structural investigations were focused on the surface of the conductive film and the interface between the AgNWs and the flexible substrate before and after strain.
The result was made a series of conductive films that have good opto-electrical properties under mechanical strain.

1.	Sun Y., Du Z. A Flexible and Highly Sensitive Pressure Sensor Based on AgNWs/NRLF for Hand Motion Monitoring // Nanomaterials.-2019.-9.P. 945.