Fernández Sánchez-Romate, Xoan XoséBosque García, Antonio delSánchez, MaríaUreña, Alejandro2023-09-252023-09-252023Electrical Transport Mechanisms in Graphene Nanoplatelet Doped Polydimethylsiloxane and Application to Ultrasensitive Temperature Sensors Xoan Xosé Fernández Sánchez-Romate, Antonio del Bosque García, María Sánchez, and Alejandro Ureña ACS Applied Materials & Interfaces 2023 15 (18), 22377-22394 DOI: 10.1021/acsami.2c221621944-8252https://hdl.handle.net/10115/24527This work was supported by the Agencia Estatal de Investigación of Spanish Government [Project MULTIFUNC-EVs PID2019-107874RB-I00], Comunidad de Madrid regional government [PROJECT ADITIMAT-CM (S2018/NMT-4411)], and Young Researchers IMPULSO program by Universidad Rey Juan Carlos [ref. 2986, SMARTSENS].The temperature effect on electronic transport mechanisms in graphene nanoplatelet (GNP) doped polydimethylsiloxane (PDMS) for temperature sensing applications has been investigated under electrical impedance spectroscopy (EIS) analysis. AC measurements showed a very prevalent frequency-dependent behavior in low filled nanocomposites due to the lower charge density. In fact, 4 wt % GNP samples showed a nonideal capacitive behavior due to scattering effects. Therefore, the standard RC-LRC circuit varies with the substitution of capacitive elements by CPEs, where a CPE is a constant phase element which denotes energy dissipation. In this regard, the temperature promotes a prevalence of scattering effects, with an increase of resistance and inductance and a decrease of capacitance values in both RC (intrinsic and contact mechanisms) and LRC (tunneling mechanisms) elements and, even, a change from ideal to nonideal capacitive behavior as in the case of 6 wt % GNP samples. In this way, a deeper understanding of electronic mechanisms depending on GNP content and temperature is achieved in a very intuitive way. Finally, a proof-of-concept carried out as temperature sensors showed a huge sensitivity (from 0.05 to 11.7 °C–1) in comparison to most of the consulted studies (below 0.01 °C–1), proving, thus, excellent capabilities never seen before for this type of application.engAtribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Graphene nanoplatelets,PDMSTemperature sensorElectrical impedance spectroscopyElectrical propertiesinfo:eu-repo/semantics/article10.1021/acsami.2c22162info:eu-repo/semantics/openAccess