Non-equilibrium compression achieving high sensitivity and linearity for iontronic pressure sensors

Jing Yang; Zhibin Li; Ying Wu; Yong Shen; Ming Zhang; Bin Chen; Guojiang Yuan; Songhua Xiao; Jiansong Feng; Xu Zhang; Yuwei Tang; Sunan Ding; Xiaolong Chen; Taihong Wang

doi:10.1016/j.scib.2024.05.001

Non-equilibrium compression achieving high sensitivity and linearity for iontronic pressure sensors

Sci Bull (Beijing). 2024 Jul 30;69(14):2221-2230. doi: 10.1016/j.scib.2024.05.001. Epub 2024 May 11.

Authors

Jing Yang¹, Zhibin Li¹, Ying Wu², Yong Shen¹, Ming Zhang³, Bin Chen⁴, Guojiang Yuan¹, Songhua Xiao¹, Jiansong Feng¹, Xu Zhang¹, Yuwei Tang¹, Sunan Ding⁵, Xiaolong Chen⁶, Taihong Wang⁷

Affiliations

¹ Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
² School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, China.
³ Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education, Engineering Research Center of Advanced Semiconductor Technology and Application of Ministry of Education, Changsha Semiconductor Technology and Application Innovation Research Institute, College of Semiconductors (College of Integrated Circuits), Hunan University, Changsha 410082, China.
⁴ School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
⁵ School of Integrated Circuits, Nanjing University, Suzhou 215163, China. Electronic address: [email protected].
⁶ Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China. Electronic address: [email protected].
⁷ Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China; School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, China. Electronic address: [email protected].

PMID: 38782658
DOI: 10.1016/j.scib.2024.05.001

Abstract

Flexible pressure sensors with high sensitivity and linearity are highly desirable for robot sensing and human physiological signal detection. However, the current strategies for stabilizing axial microstructures (e.g., micro-pyramids) are mainly susceptible to structural stiffening during compression, thereby limiting the realization of high sensitivity and linearity. Here, we report a bending-induced non-equilibrium compression process that effectively enhances the compressibility of microstructures, thereby crucially improving the efficiency of interfacial area growth of electric double layer (EDL). Based on this principle, we fabricate an iontronic flexible pressure sensor with vertical graphene (VG) array electrodes. Ultra-high sensitivity (185.09 kPa^-1) and linearity (R² = 0.9999) are realized over a wide pressure range (0.49 Pa-66.67 kPa). It also exhibits remarkable mechanical stability during compression and bending. The sensor is successfully employed in a robotic gripping task to recognize the targets of different materials and shapes based on a multilayer perception (MLP) neural network. It opens the door to realizing haptic sensing capabilities for robotic hands and prosthetic limbs.

Keywords: Artificial mechanoreceptor; E-skin; Ionic nanofiber; Object recognition; Pressure sensor; Vertical grapheme.