A Flexible Temperature Sensor Based on Reduced Graphene Oxide for Robot Skin Used in Internet of Things

Flexible electronics, which can be distributed on any surface we need, are highly demanded in the development of Internet of Things (IoT), robot technology and electronic skins. Temperature is a fundamental physical parameter, and it is an important indicator in many applications. Therefore, a flexible temperature sensor is required. Here, we report a simple method to fabricate three lightweight, low-cost and flexible temperature sensors, whose sensitive materials are reduced graphene oxide (r-GO), single-walled carbon nanotubes (SWCNTs) and multi-wall carbon nanotubes (MWCNTs). By comparing linearity, sensitive and repeatability, we found that the r-GO temperature sensor had the most balanced performance. Furthermore, the r-GO temperature sensor showed good mechanical properties and it could be bent in different angles with negligible resistance change. In addition, the performance of the r-GO temperature sensor remained stable under different kinds of pressure and was unaffected by surrounding environments, like humidity or other gases, because of the insulating layer on its sensitive layer. The easy-fabricated process and economy, together with the remarkable performance of the r-GO temperature sensor, suggest that it is suitable for use as a robot skin or used in the environment of IoT.

[1]  J. Nakamura,et al.  Semiconducting nature of the oxygen-adsorbed graphene sheet , 2008 .

[2]  Tae Won Kang,et al.  A patterned single layer graphene resistance temperature sensor , 2017, Scientific Reports.

[3]  Richard Kennon,et al.  Preliminary Investigations intothe Development of Textile Based Temperature Sensor for Healthcare Applications , 2013 .

[4]  Lin Jia,et al.  Epidermal photonic devices for quantitative imaging of temperature and thermal transport characteristics of the skin , 2014, Nature Communications.

[5]  Ting Wang,et al.  Soft Thermal Sensor with Mechanical Adaptability , 2016, Advanced materials.

[6]  Chunya Wang,et al.  An All-Silk-Derived Dual-Mode E-skin for Simultaneous Temperature-Pressure Detection. , 2017, ACS applied materials & interfaces.

[7]  Di Zhang,et al.  Bioinspired Engineering of Thermal Materials , 2015, Advanced materials.

[8]  Dae-Hyeong Kim,et al.  Multifunctional wearable devices for diagnosis and therapy of movement disorders. , 2014, Nature nanotechnology.

[9]  D. Teweldebrhan,et al.  High-temperature quenching of electrical resistance in graphene interconnects , 2008 .

[10]  Seiji Akita,et al.  Toward Flexible and Wearable Human‐Interactive Health‐Monitoring Devices , 2015, Advanced healthcare materials.

[11]  U. Chung,et al.  Highly Stretchable Resistive Pressure Sensors Using a Conductive Elastomeric Composite on a Micropyramid Array , 2014, Advanced materials.

[12]  Chi-Yuan Lee,et al.  Use of flexible micro-temperature sensor to determine temperature in situ and to simulate a proton exchange membrane fuel cell , 2011 .

[13]  X. Yi,et al.  Thermal volume expansion in polymeric PTC composites: a theoretical approach , 2001 .

[14]  Bin Yu,et al.  Highly sensitive flexible tactile sensors based on microstructured multiwall carbon nanotube arrays , 2017 .

[15]  Yonggang Huang,et al.  Ultrathin conformal devices for precise and continuous thermal characterization of human skin. , 2013, Nature materials.

[16]  Seiji Akita,et al.  Highly selective flexible tactile strain and temperature sensors against substrate bending for an artificial skin , 2015 .

[17]  T. Trung,et al.  Flexible and Stretchable Physical Sensor Integrated Platforms for Wearable Human‐Activity Monitoringand Personal Healthcare , 2016, Advanced materials.

[18]  Moinuddin Ahmed,et al.  Temperature Sensor in a Flexible Substrate , 2012, IEEE Sensors Journal.

[19]  M. Bendahan,et al.  Temperature sensor realized by inkjet printing process on flexible substrate , 2016 .

[20]  Xin Ding,et al.  Review of Flexible Temperature Sensing Networks for Wearable Physiological Monitoring , 2017, Advanced healthcare materials.

[21]  A. Balandin,et al.  Thermal properties of graphene and multilayer graphene: Applications in thermal interface materials , 2012 .

[22]  Benjamin C. K. Tee,et al.  Highly sensitive flexible pressure sensors with microstructured rubber dielectric layers. , 2010, Nature materials.

[23]  Kuang-Chao Fan,et al.  Flexible Temperature Sensor Array Based on a Graphite-Polydimethylsiloxane Composite , 2010, Sensors.

[24]  Xiaodong Chen,et al.  Flexible and Stretchable Devices , 2016, Advanced materials.

[25]  Chi-Yuan Lee,et al.  In Situ Monitoring of Temperature inside Lithium-Ion Batteries by Flexible Micro Temperature Sensors , 2011, Sensors.

[26]  K. Mabuchi,et al.  Ultraflexible, large-area, physiological temperature sensors for multipoint measurements , 2015, Proceedings of the National Academy of Sciences.

[27]  T. Arie,et al.  Fully printed flexible fingerprint-like three-axis tactile and slip force and temperature sensors for artificial skin. , 2014, ACS nano.

[28]  Benjamin C. K. Tee,et al.  25th Anniversary Article: The Evolution of Electronic Skin (E‐Skin): A Brief History, Design Considerations, and Recent Progress , 2013, Advanced materials.

[29]  Chaoyi Yan,et al.  Stretchable graphene thermistor with tunable thermal index. , 2015, ACS nano.

[30]  Kishor Kumar Sadasivuni,et al.  Reduced graphene oxide filled cellulose films for flexible temperature sensor application , 2015 .