2024-03-29T09:59:34Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1269062016-02-18T03:30:00Zcom_10261_10252com_10261_3col_10261_10253
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Fattah, Ali
author
Khatami, Saeid
author
Mayorga-Martínez, Carmen C.
author
Medina-Sánchez, Mariana
author
Baptista-Pires, Luis
author
Merkoçi, Arben
author
2014
A graphene(G)/Silicon(Si) heterojunction Schottky diode and a simple method that evaluates its electrical response to different chemical vapors using electrochemical impedance spectroscopy (EIS) are implemented. To study the impedance response of the device of a given vapor, relative impedance change (RIC) as a function of the frequency is evaluated. The minimum value of RIC for different vapors corresponds to different frequency values (18.7, 12.9 and 10.7 KHz for chloroform, phenol, and methanol vapors respectively). The impedance responses to phenol, beside other gases used as model analytes for different vapor concentrations are studied. The equivalent circuit of the device is obtained and simplifi ed, using data fi tting from the extracted values of resistances and capacitances. The resistance corresponding to interphase G/Si is used as a parameter to compare the performance of this device upon different phenol concentrations and a high reproducibility with a 4.4% relative standard deviation is obtained. The effi ciency of the device fabrication, its selectivity, reproducibility and easy measurement mode using EIS makes the developed system an interesting alternative for gases detection for environmental monitoring and other industrial applications.
Small 10(20): 4193-4199 (2014)
http://hdl.handle.net/10261/126906
10.1002/smll.201400691
http://dx.doi.org/10.13039/501100004837
Graphene/Silicon heterojunction schottky diode for vapors sensing using impedance spectroscopy