【摘要】：Stretchable and conformal humidity sensors that can be attached to the human body for continuously monitoring the humidity of the environment around the human body or the moisture level of the human skin can play an important role in electronic skin and personal healthcare applications. However, most stretchable humidity sensors are based on the geometric engineering of non-stretchable components and only a few detailed studies are available on stretchable humidity sensors under applied mechanical deformations. In this paper, we propose a transparent, stretchable humidity sensor with a simple fabrication process, having intrinsically stretchable components that provide high stretchability, sensitivity, and stability along with fast response and relaxation time. Composed of reduced graphene oxide-polyurethane composites and an elastomeric conductive electrode, this device exhibits impressive response and relaxation time as fast as 3.5 and 7 s, respectively. The responsivity and the response and relaxation time of the device in the presence of humidity remain almost unchanged under stretching up to a strain of 60% and after 10,000 stretching cycles at a 40% strain. Further, these stretchable humidity sensors can be easily and conformally attached to a finger for monitoring the humidity levels of the environment around the human body, wet objects, or human skin.
【资金项目】：this research was supported by the basic science research program (no.2013r1a2a1a01015232) of the national research foundation of korea funded by the ministry of science，ict and future planning
【作者单位】：School of Advanced Materials Science & Engineering,Sungkyunkwan University (SKKU),Suwon,Kyunggi-do 16419,Republic of Korea；Center for Water Resource Cycle Research,Korea Institute of Science and Technology,Hwarang-ro 14 gil,Seongbuk-gu,Seoul 02793,Republic of Korea；SKKU Advanced Institute of Nanotechnology (SAINT),SKKU,Suwon,Kyunggi-do 16419,Republic of Korea；Samsung Advanced Institute for Health Sciences & Technology (SAIHST),SKKU,Suwon,Kyunggi-do 16419,Republic of Korea