Sputtered Thermoelectric Nanoparticles for an Ultra-Thin, Flexible and Cuttable Self-Powered Temperature Sensor

Abstract

Inadequate energy for the growing population has been a major concern in the recent years. Though efforts are being made to alleviate this problem, the crisis still exists. For this reason, the focus of the scientific community is directed towards self-powered technology. As technology is getting smart, smart sensors are also gaining attention. Human beings are getting more and more concerned about their health and opt for the best personalized health care devices. Body temperature is a vital sign which reflects the health condition and thermoregulation in human beings. For continuous monitoring of body temperature, devices which are compact, lightweight and self-powered is therefore desirable. So, we design a highly flexible, ultra-thin and conformable temperature sensor which just uses heat from the body as a power source and senses the body temperature precisely. The sensor works on thermoelectric effect and can detect any surface temperature from room temperature to 100 ˚C and also room temperature to 0 ˚C. For a temperature gradient of 75 ˚C the sensor gives and output voltage of 0.4 mV and can even detect a human finger touch with an accurate body temperature. Such flexible and thin device can be used in day to day monitoring of human beings enabling it to be used as a wearable temperature sensor, hot or cold surface temperature measurement which may create injury if touched or as a biomedical device for the measurement of hyperthermia or even monitoring the health of pets.

Emergence of Non‐photoresponsive Catalytic Techniques for Environmental Remediation and Energy Generation

“…thermoelectric and pyroelectric materials. [25][26][27][28] In 2012, Wang group first invented a triboelectric nanogenerator (TENG) in which charges accumulate on the surface of material after contacting other heterogeneous materials via friction. [29] TENG are based on triboelectric materials which can effectively harvest low grade mechanical energy from various sources, such as body movement, fluid flow, and acoustic waves; these energies are usually wasted in our daily life.…”

“…Positive charges build up on one side of a piezoelectric material due to electric dipole modulation, whereas negative charges build up on the opposing side [23,24] . Second, temperature‐based materials that generate positive and negative charges by triggering temperature fluctuations that cause spatial motion of atoms in the crystal structures, leading to switching of polarization inside thermoelectric and pyroelectric materials [25–28] . In 2012, Wang group first invented a triboelectric nanogenerator (TENG) in which charges accumulate on the surface of material after contacting other heterogeneous materials via friction [29] .…”

The Interface between Nanoenergy and Self-Powered Electronics

“…Therefore, just by directly reading the output signals of nanogenerators, people or machines can detect environmental changes in real time. In recent years, the output characteristics of many different types of nanogenerators have been demonstrated to indicate motions and gestures [ 34 , 35 ], acceleration [ 36 , 37 ], force [ 38 , 39 ], temperature [ 40 , 41 ], and humidity [ 42 , 43 ], according to the quantitative relationship between external stimuli and the waveform and amplitude of the electrical output. In this section, four typical self-powered sensors are selected, and they are summarized in Figure 1 .…”

Energy Harvesting Untethered Soft Electronic Devices

“…Ultrasonic devices can generate signals from beneath human skin, therefore allowing remote transmission through human biomechanics. [ 25–29 ] Several designs and fabrication methods for thermoelectric materials have recently been reported to achieve mechanically compliant properties.…”