An Ultra‐Mechanosensitive Visco‐Poroelastic Polymer Ion Pump for Continuous Self‐Powering Kinematic Triboelectric Nanogenerators

• Published in: Advanced energy materials Vol. 9; no. 17
• Main Authors: Hwang, Hee Jae, Kim, Joo Sung, Kim, Wook, Park, Hyunwoo, Bhatia, Divij, Jee, Eunsong, Chung, Yoon Sun, Kim, Do Hwan, Choi, Dukhyun
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-05-2019
• Subjects: continuous operation; Deformation mechanisms; Electrochemical analysis; Formability; Gear trains; ionic triboelectric nanogenerators; Kinematics; Nanogenerators; Optical properties; polymer ion pumps; Polymers; Sensor arrays; Tactile sensors (robotics); visco‐poroelastic; Wireless communications
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.201803786

A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa−1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm−2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array.
An ultra‐mechanosensitive polymer ion pump and a kinematic architecture are presented for an innovative system design of ionic triboelectric nanogenerators (iTENGs). A visco‐poroelastic ion pump dramatically enhances output of iTENGs via establishing an electrical double layer. Furthermore, a kinematic architecture is integrated using a gear and a cam with iTENGs, which regulates a low frequency into a high working frequency.