All-Carbon Based Flexible Humidity Sensor

Author(s)

Wu, Yichuan ^{[1, 2, 3]} ; Huang, Qiyang ^[2] ; Nie, Jing ^{[1, 3]} ; Liang, Jiaming ^{[1, 2, 3]} ; Joshi, Nirav ^{[4, 1, 3]} ; Hayasaka, Takeshi ^{[1, 3]} ; Zhao, Shilong ^{[1, 3]} ; Zhang, Min ^[5] ; Wang, Xiaohao ^{[2, 5]} ; Lin, Liwei ^{[1, 2, 3]}

Affiliation

^[1] Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 - USA

^[2] Tsinghua Univ, Tsinghua Berkeley Shenzhen Inst, Shenzhen 518055 - Peoples R China

^[3] Univ Calif Berkeley, Berkeley Sensors & Actuators Ctr, Berkeley, CA 94720 - USA

^[4] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13560970 Sao Carlos, SP - Brazil

^[5] Tsinghua Univ, Grad Sch Shenzhen, Shenzhen 518055 - Peoples R China

• Document type: Journal article
• Source: Journal of Nanoscience and Nanotechnology; v. 19, n. 8, p. 5310-5316, AUG 2019.
• Web of Science Citations: 0

Abstract

Flexible humidity sensors play important roles in wearable devices and consuming electronics which provide a convenient way between digital and physical worlds. This work presents an easy fabricated method for flexible humidity sensors all based on carbon material including electrodes and functional layers. The interdigital electrodes are made by direct laser writing on commercial Kapton tapes and the transferring to flexible Polydimethylsiloxane (PDMS) substrates. The humidity sensing material is reduced graphene oxide (rGO) in nanometer thickness by electrospray. The rGO flakes covered the micro-size laser induced graphite (LIG), forming rGO-graphite balls, dramatically increase surface areas to interact with water molecules. The results show high precision sensitivity and fast response time for adsorption (0.9 s) and desorption (4.5 s). This method provides a novel method for fabricating cost-effective flexible humidity sensors. (AU)

• FAPESP's process: 16/23474-6 - Nanomaterial-based heterostructures: synthesis and their gas sensing properties
• Grantee: Niravkumar Jitendrabhai Joshi
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 14/23546-1 - Enhanced sensitive and selective sensors made with p-NiO nanowire/n-ZnO Nanowire heterostructures
• Grantee: Niravkumar Jitendrabhai Joshi
• Support Opportunities: Scholarships in Brazil - Post-Doctoral