Self-powered Temperature Sensor Research Articles

Durable and Wearable Self-powered Temperature Sensor Based on Self-healing Thermoelectric Fiber by Coaxial Wet Spinning Strategy for Fire Safety of Firefighting Clothing

Durable and Wearable Self-powered Temperature Sensor Based on Self-healing Thermoelectric Fiber by Coaxial Wet Spinning Strategy for Fire Safety of Firefighting Clothing

Self-powered temperature sensors harnessing membrane potential of living cells

In this paper we present a novel method for remote temperature measurements of a bio-cell and its immediate surroundings, based on the use of electrical energy harvested from a single soleus muscle fiber. Our method employs an optimized RLC circuit, embedded with the cell, where the capacitor serves both as an energy storage unit and a temperature sensor, exploiting its natural temperature sensitivity. Once charged, the RLC oscillator emits a radio signal at a frequency that is dependent on the temperature. This signal can be received wirelessly through a receiver, facilitating remote temperature measurement. We present experimental tests performed on soleus muscle from mouse, where a maximum output voltage of – 70 mV is attained on a 1 mF capacitor. The experimental data confirm that our system can exploit the energy harvested from the cell membrane to communicate wirelessly the temperature and it can be employed in the range of biological interest (30 °C to 50 °C). Such self-powered temperature sensors have the potential to improve the field of biomedical sensing and non-invasive remote temperature monitoring.

Self-Powered Temperature Electronic Skin Based on Island-Bridge Structure and Bi-Te Micro-Thermoelectric Generator for Distributed Mini-Region Sensing.

Thermoelectric (TE) effect based temperature sensor can accurately convert temperature signal into voltage without external power supply, which have great application prospects in self-powered temperature electronic skin (STES). But the fabrication of stretchable and distributed STES still remains a challenge. Here, a novel STES design strategy is proposed by combining flexible island-bridge structure with BiTe-based micro-thermoelectric generator (µ-TEG). Furthermore, a 4×4 vertical temperature sensor array with good stretchability and distributed sensing property has been fabricated for the first time. The interfacial chemical bonds located between the rigid islands (µ-TEG) and the flexible substrate (polydimethylsiloxane, PDMS) endow the STES with excellent stretchability, and its sensing performance remains unchanged under 30% strain (the maximum strain of human skin). Moreover, the STES sensing unit possesses high sensitivity (729 µV K-1 ), rapid response time (0.157 s), and high spatial resolution (2.75×2.75 mm2 ). As a proof of concept, this work demonstrates the application of the STES in the detection of mini-region heat sources in various scenarios including noncontact spatial temperature responsing, intelligent robotic thermosensing, and wearable temperature sensing. Such an inspiring design strategy is expected to provide guidance for the design and fabrication of wearable self-powered temperature sensors.

High-Performance thermoelectric generator based on n-Type flexible composite and its application in Self-Powered temperature sensor

Thermoelectric generators (TEGs) present a promising alternative to conventional power generation technologies for powering low-power wearable electronics. However, there are few n-type organic materials with high thermoelectric and mechanical performance. In this study, a polymer (PEI-PFA) via low temperature polycondensation between polyethyleneimine (PEI) and paraformaldehyde (PFA) is synthesized, and this is the first reported polymer which can be not only used as a novel n-type dopant of single-walled carbon nanotubes (SWCNTs) due to the PEI moieties, but also endow the composites with good flexibility due to the synthesized hemiaminal dynamic covalent networks. Subsequent addition of sodium hydroxide (NaOH) can further enhance the electron conductivity. The resulting SWCNT/PEI-PFA/NaOH composite film exhibits an excellent electrical conductivity of 1641.22 S cm−1, a power factor of 115.77 μW m−1 K−2, a tensile strength of 36.4 MPa, and flexibility up to 21 % strain. In addition, a self-powered sensor is assembled, which can efficiently monitor temperature changes and strain deformations. Moreover, a thermoelectric device containing five p-n junctions based on the pristine SWCNTs and SWCNT/PEI-PFA/NaOH composite is prepared, and a high output power of 5.33 μW at the temperature difference of 75.2 K is achieved. This work presents a promising approach to developing flexible n-type thermoelectric materials for self-powered wearable electronics.

Cotton Based Self-Powered Temperature Sensor Based on Au-Augmented WS2 Triboelectric Nanogenerator

Cotton Based Self-Powered Temperature Sensor Based on Au-Augmented WS2 Triboelectric Nanogenerator

Temperature and Humidity Wireless Sensor System based on Bluetooth Low Energy and Solar Self-power

According to the actual needs of the modern greenhouse, this paper designs a low-energy solar self-powered temperature and humidity wireless sensor system based on Bluetooth low energy. The system uses a Panasonic AM-1801 solar panel and S6AE103A single-chip microcomputer as the energy management module to realize the self-power supply of the system, and uses Si7202-A20-IM1 as the sensor module to collect the temperature and humidity in the environment. The monitoring data are transmitted through the Bluetooth wireless network. The receiving end of the upper computer uses the CY8C5868LTI-LP039 module USB Dongle to receive data. The system realizes the wireless data transmission of the temperature and humidity sensor in the greenhouse environment and the real-time network monitoring of the ambient temperature and humidity through the Bluetooth network. This system can be applied to various greenhouse systems.

Hydrogen-bonded n-type waterborne polyurethane/lysine/single-walled carbon nanotube ternary composite: Combining excellent thermoelectric and stretchable properties toward self-powered temperature and strain sensors

Hydrogen-bonded n-type waterborne polyurethane/lysine/single-walled carbon nanotube ternary composite: Combining excellent thermoelectric and stretchable properties toward self-powered temperature and strain sensors

A Flexible and Stretchable Temperature Sensor Based on Contact Electrification for Robotic Sensing

With the rapid development of robotic systems, an increasing number of various sensitive sensors are needed to meet the requirement of data collection for unmanned detection and monitoring technology. Among various external stimuli information, temperature sensing is an essential important function that can avoid high-temperature scalding injuries, achieve robot detection of environmental, and human-machine interfaces applications. However, most of the existing temperature sensors for robotic sensing are realized by rigid materials, which have the disadvantage of not being able to adapt to an arbitrarily curved surface. Also, most of the sensors are thermistor-based approaches, which faces challenges in developing a low-cost robotic system since external power is required to obtain the sensing signal. In this work, a self-powered and stretchable temperature sensor based on Triboelectric Nanogenerator (TENG) technology was developed. The principle of TENG is the coupling effect of triboelectric charge transfer and electrostatic induction effects, which can generate different magnitudes of electrical signals when subjected to external stimuli, including temperature. To this end, this study is a pilot effort toward validating the sensitivity of TENG electrical output on different temperature effects. The surface potential of materials is explored under different temperatures by Kelvin probe force microscopy (KPFM), which shows the feasibility of self-powered temperature sensor. The proposed temperature sensor is composed of highly resilient materials physiological saline as liquid electrode encapsulated with Ecoflex as triboelectric layer, which has the advantage of biocompatibility. The temperature sensing performance was successfully maintained at 200% stretch. Owing to its flexible, bendable and stretchable characteristics, the self-powered temperature-sensitive sensor has been successfully demonstrated on a robot hand, which can read the information and respond to different temperatures through the feedback system. Overall, this self-powered temperature-sensitive sensor has great potential to be an emerging tool for human-robot interaction and automatic detection.

Ultra-flexible self-supporting Ag2Se/nylon composite films for wearable thermoelectric devices

Recently, flexible thermoelectric (TE) generators (f-TEGs) have received a lot of attention. Compared with TE films on flexible substrates, self-supporting composite films prepared by combining TE materials with soft fabrics and thus retaining the inherent advantages of fabrics, such as stretchability, breathability, and flexibility, are more practical and may significantly expand the application of f-TEGs in smart wearable devices. Hence, in this work, a facile and rapid method for preparing ultra-flexible self-supporting Ag2Se/nylon composite films is developed. The composite films with both TE properties and flexibility were obtained by fast selenization of commercial Ag/nylon fiber fabrics in a short time (60 s) at room temperature and then hot pressing at 230 °C in a vacuum. The maximum power factor of an optimized composite film at room temperature can reach 73.7 μW m−1 K−2. Meanwhile, the film exhibits excellent flexibility with the Seebeck coefficient and electrical conductivity decreased by only 7.37 and 8.48% after being bent 4000 repetitions around a round bar with a radius of 4 mm, which exceeds most reported flexible TE films. The ultra-high flexibility is mainly attributed to its high content of the nylon matrix (∼85.05 wt%), the tight bonding between Ag2Se grains, and the good combination between the Ag2Se and nylon matrix. In addition, a 3-leg f-TEG assembled with the optimal film produces a maximum power of ∼1.524 μW (corresponding to a power density of ∼0.47 W m−2) at a temperature gradient of 40.6 K, verifying the good TE performance of the composite film. This f-TEG can also be used as a self-powered temperature sensor, showing potential applications in daily life.

Biodegradable hyaluronic acid-based triboelectric nanogenerator as self-powered temperature sensor

Bio-based energy harvesting devices must make use of building blocks that incorporate intrinsic properties of flexibility, transparency, mechanical resistance and potential to harvest energy in contact with the body. The use of hyaluronic acid film as a tribopositive layer represents a promising strategy in bioelectronics for the development of battery-free devices. Herein, it is reported a new triboelectric nanogenerator based on the hyaluronic acid film with promising electrical output (voltage of 398.5 V and current of 21.9 μA) with a linear variation in the open circuit voltage as a function of the temperature that was explored in a prototype of a self-powered temperature sensor applied in the range of the 27 °C – 43 °C.

Integrated Piezo-Triboelectric Nanogenerators-Based Self-Powered Flexible Temperature and Pressure Sensor

Efficient harvesting of ubiquitous ambient mechanical energy using various types of nanogenerators (NGs) has attracted considerable interest in recent years. Herein, we present a textile triboelectric nanogenerator (T-TENG) using Polytetrafluoroethylene (PTFE) and Nylon based counter-surfaces in fabric form (both fixed to conductive fabric electrodes). T-TENG performance is enhanced by exposing PTFE film with Argon plasma. The output voltage of the plasma treated devices increased by a factor of ~10, and their short circuit current density increased by a factor of ~9 (compared to pristine non-plasma treated devices). Additionally, we demonstrate that the fabricated T-TENG can be used as a self-powered temperature sensor, tested in the 25-90 °C range. The T-TENG output voltage decreased linearly with increasing temperature exhibiting a sensitivity of ~ 1%/(°C). Further, we integrated a flexible piezoelectric nanogenerator (PENG) on top of the T-TENG to detect the contact forces. The PENG output is also used to compensate the pressure dependent output of TENG underneath, and allows distinct temperature and pressure measurements. The excellent results observed here show the potential of T-TENGs for use as self-powered sensors in applications such as health monitoring, wearables and interactive systems.

A New Self-Powered Temperature Sensor Based on Thermoelectric Generators

This article presents a new self-powered temperature sensor based on thermoelectric generators (TEGs). Two different types of TEGs measure temperature and supply the interface circuit. The interface circuit calculates and generates an output current proportional to the cold-surface temperature of the TEGs. Since TEG output voltage depends on the temperature difference between the cold and hot surfaces, a three-terminal TEG has been used. A combination structure of the two PbTe and Bi2Te3 TEGs are thermally in parallel and electrically in series. The new method uses a machine-learning algorithm and Seebeck curve fitting for temperature calculation. For the cold surface temperature range of 0 °C to 70 °C, the error is less than ±1 °C.

Facile fabrication of stretchable and multifunctional thermoelectric composite fabrics with strain-enhanced self-powered sensing performance

Self-powered sensors have attracted extensive attention, which are farbicated based on thermoelectric materials that can operate in a self-powered mode. Their development faces challenges of limited preparation methods, complex structures and unstable sensing performance caused by the reduce of output signal during stretching. In this work, we prepared a thermoelectric composite fabric based on carbon nanotube (CNT)/polyvinyl pyrrolidone (PVP) by a facile ultrasonic coating method and further extended its application in self-powered temperature/strain sensing. PVP was used to disperse CNTs and increase the bonding force between fabric and CNTs, therefore maintaining stable thermoelectric properties under repeated bending and stretching. The presented self-powered temperature sensors show great potential in temperature recognition and breathing monitoring. Moreover, they additionally exhibits enhanced output signal upon stretching because of knitted fabric structure, which enables baseball players to optimize training behaviors.

Phase transition enhanced pyroelectric nanogenerators for self-powered temperature sensors

Pyroelectric materials are of interest for waste heat utilization and thermal detection. However, the low output current and inefficiency reduces their effectiveness. Here, we utilize the abrupt decrease in polarization of ferroelectric BaTiO3 materials around Curie temperature to improve the output performance of a pyroelectric nanogenerator. The variation of the polarization leads to a large change in the density of surface free charges, resulting in an increase of pyroelectric current. We have designed a temperature control and recording system to realize direct measurement of the pyroelectric output current. The pyroelectric current, power and energy conversion efficiency of the device near the Curie temperature were measured to be 15.6-fold, 18-fold and 15.8-fold higher than those acquired near room temperature. Moreover, the temperature induced current and charge density enhancement can be applied to detect temperature and temperature change. The responsivity of the self-powered temperature sensor near Tc is 120 nC/cm2∙K, which 4.8 times higher than that near room temperature (25.1 nC/cm2∙K). The results confirmed the ability to exploit a ferroelectric phase transition for pyroelectric performance enhancement.

Light-Harvesting Self-Powered Monolithic-Structure Temperature Sensing Based on 3C-SiC/Si Heterostructure.

Utilizing harvesting energy to power sensors has been becoming more critical in the current age of the Internet of Things. In this paper, we propose a novel technology using a monolithic 3C-SiC/Si heterostructure to harvest photon energy to power itself and simultaneously sense the surrounding temperature. The 3C-SiC/Si heterostructure converts photon energy into electrical energy, which is manifested as a lateral photovoltage across the top material layer of the heterostructure. Simultaneously, the lateral photovoltage varies with the surrounding temperature, and this photovoltage variation with temperature is used to monitor the temperature. We characterized the thermoresistive properties of the 3C-SiC/Si heterostructure, evaluated its energy conversion, and investigated its performance as a light-harvesting self-powered temperature sensor. The resistance of the heterostructure gradually drops with increasing temperature with a temperature coefficient of resistance (TCR) ranging from more than -3500 to approximately -8200 ppm/K. The generated lateral photovoltage is as high as 58.8 mV under 12 700 lx light illumination at 25 °C. The sensitivity of the sensor in the self-power mode is as high as 360 μV·K-1 and 330 μV·K-1 under illumination of 12 700 lx and 7400 lx lights, respectively. The sensor harvests photon energy to power itself and measure temperatures as high as 300 °C, which is impressive for semiconductor-based sensor. The proposed technology opens new avenues for energy harvesting self-powered temperature sensors.

Coaxial Spring-Like Stretchable Triboelectric Nanogenerator Toward Personal Healthcare Monitoring.

Stretchable triboelectric nanogenerators have attracted increasing interests in the field of Internet of Things and sensor network. Therefore, great efforts have been made to realize the stretchability of electronic devices via elaborated material configurations and ingenious device designs. In this work, a flexible and stretchable TENG is developed with a coaxial spring-like structure. The unique structure allows it to generate electrical energy for different degrees of stretching deformations. Its output demonstrates good response to the strain and frequency of the mechanical deformation. At the same time, it exhibits excellent stability and washability. The TENG can be worn on the human fingers, elbow, and knee to monitor the body activities. Furthermore, a self-powered temperature sensor system is fabricated by integrating the TENG with a temperature sensor to identify the operating ambient temperature in real time. A combination of this flexible and stretchable TENG with body motions and a temperature sensor brings a novel insight into wearable functional electronics and user-friendly health monitoring, which has an important basic research significance and practical application value in biometric systems.

Phase Transition Enhanced Pyroelectric Nanogenerators for Self-Powered Temperature Sensors

Phase Transition Enhanced Pyroelectric Nanogenerators for Self-Powered Temperature Sensors

Self-Powered Photovoltaic Bluetooth® Low Energy Temperature Sensor Node

A wireless self-powered temperature sensor node is presented. This sensor node is powered by a commercially available indoor photovoltaic energy harvester module. The sensor node uses Bluetooth® Low Energy as wireless connection. Both the hardware and firmware have been optimized to obtain a very low power consumption. An auto adaptive energy management routine has been implemented to extend the autonomy of the sensor node. The system consumption and photovoltaic generation have been characterized at different conditions, obtaining a tool to estimate the autonomy of the system. The system has also been tested in a climatic chamber to study the effect of the temperature, a key factor that affects the power consumption, and hence the autonomy of the sensor.

Double-piezoelectric-layer-enhanced triboelectric nanogenerator for bio-mechanical energy harvesting and hot airflow monitoring

Recently, the vigorous development of flexible piezoelectric nanogenerator and triboelectric nanogenerator (TENG) has attracted more and more attention from researchers. In this paper, we reported a novel double-piezoelectric-layer-enhanced TENG (DP-TENG) to harvest mechanical energy. The DP-TENG can also serve as a self-powered deformation sensor to detect bending motion. To realize the large-scale production and wide application, a sample fabrication method was developed to prepare DP-TENG using low-cost commercial materials, such as PTFE film, Nylon film, and PVDF film. Besides, the DP-TENG can be used to monitor the flow of hot air to serve as a self-powered temperature sensor. This research has provided an effective structural design about piezoelectric-enhanced TENG for harvesting environment mechanical energy, which has bright potentials in the field of self-power deformation system and airflow temperature monitoring.

Ultrathin and Flexible Self-powered Temperature Sensor Based on Sputtered Tellurium Nanoparticles

Ultrathin and Flexible Self-powered Temperature Sensor Based on Sputtered Tellurium Nanoparticles