SiCNO–GO composites with the negative temperature coefficient of resistance for high‐temperature sensor applications

Abstract

We report the synthesis of silicon oxycarbonitride ceramic‐graphene oxide (SiCNO–GO) composites by using polyvinylsilazne (PVSZ) and GO as precursors through cross‐linking processes, in which GO organizes into microspheres in the SiCNO matrix. The formation of GO microspheres significantly enhances the electrical conductivity of SiCNO. The electrical resistivity of SiCNO–GO composites shows a negative temperature coefficient in the range from 25°C to 600°C. We demonstrate the application of SiCNO–GO composites as the functional component of high‐temperature sensors.

Activated Carbon Obtained from Bamboo: Synthesis, Morphological, Vibrational, and Electrical Properties and Possible Temperature Sensor

“… where α is the temperature coefficient, R is the sensor resistance, and dR/dT is the resistance derivative with respect to temperature. The NTC for the temperature sensor was calculated from Equation , obtaining a value of −4.7%/K at 321.1 K, this NTC of resistance agrees with values reported by Xie et al, of −4.95%/K at 300 K …”

“…Table presents an electrical characteristics comparison between the AC NTC temperature sensor proposed in this work and three different alternatives of temperature sensors, like ([Ba, Sr] TiO 3 ) NTC thermistor, silicon oxycarbonitride ceramic‐graphene oxide (SiCNO‐GO) NTC thermistor, and low‐density polyethylene/graphite (LDPE/G) PTC thermistor . It is possible to observe that our AC temperature sensor based on AC material (produced sustainably) exhibits electrical linear response with good sensitivity.…”

“…This work reports the synthesis process and morphological, elemental, optical, and vibrational characterization of AC obtained from bamboo, determining its chemical composition, identifying vibrational response and functional groups, as well as thermal stability, which allowed proposing an approximate structure of this material and suggesting the development of NTC temperature sensors based on AC obtained from bamboo with attractive response as thermoresistive sensors . The NTC temperature sensor proposed in this work presents linear response and sensitivity at 127.7 μA K −1 in the temperature range varying from 321.1 to 447.8 K. It is low cost compared with more sophisticated non‐linear NTC thermistors …”

“…Negative temperature coefficient (NTC) temperature sensors are thermistors that, as temperature increases, decrease resistance and voltage, that is, increased concentration of charge carriers increases electrical conductivity. Furthermore, NTC thermistors have been extensively studied and manufactured according to specialized literature from SiO 2 in (Mn 1:2 Ni 0:78 Co 0:87‐x Cu 0:15 Si x ) O 4 , (Ba, Sr) TiO 3 single‐crystal films, NiMnFeCrO, ceramics in CaCeNbMO (M 5 Mo or W), MnCoNiO, Al + implanted 4H‐SiC p + −in, Pd‐loaded WO 3 , and SiCNO‐GO . Development of thermistors requires for materials exhibit high electrical conductivity and a low thermal conductivity .…”

Low‐frequency dielectric dispersion in polymer‐derived amorphous silicon carbonitride ceramics

“…For example, the electrical conductivity of these materials and their temperature dependence were found to be closely related to the characteristics of the free‐carbon clusters, following a band‐tail hopping process . Therefore, PDCs have been reported as high‐temperature sensors in virtue of these electrical conductivity characteristics . The permittivity of PDC‐SiCN at the GHz range has been reported to increase with temperature over the 50‐500°C range, and this dielectric behavior of PDCs has been used to develop wireless temperature sensors .…”