TY - JOUR
T1 - Edge-Functionalized Graphene Nanoribbon Chemical Sensor
T2 - Comparison with Carbon Nanotube and Graphene
AU - Cho, Kyeong Min
AU - Cho, Soo Yeon
AU - Chong, Sanggyu
AU - Koh, Hyeong Jun
AU - Kim, Dae Woo
AU - Kim, Jihan
AU - Jung, Hee Tae
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/12/12
Y1 - 2018/12/12
N2 - With growing focus on the use of carbon nanomaterials in chemical sensors, one-dimensional graphene nanoribbon (GNR) has become one of the most attractive channel materials, owing to its enhanced conductance fluctuation by quantum confinement effects and dense, abundant edge sites. Due to the narrow width of a basal plane with one-dimensional morphology, chemical modification of edge sites would greatly affect the electrical channel properties of a GNR. Here, we demonstrate for the first time that chemically functionalizing the edge sites with aminopropylsilane (APS) molecules can significantly enhance the sensing performance of the GNR sensor. The resulting APS-functionalized GNR has a sensitivity ((Î"R/R b ) max ) of â30% at 0.125 ppm nitrogen dioxide (NO 2 ) and an ultrafast response time (â6 s), which are, respectively, 7- and 15-fold enhancements compared to a pristine GNR sensor. This is the fastest and most sensitive gas-sensing performance of all GNR sensors reported. To demonstrate the superiority of the GNR-APS sensor, we compare its sensing performance with that of APS-functionalized carbon nanotube (CNT) and reduced graphene oxide (rGO) sensors prepared in identical synthesis conditions. Very interestingly, the GNR-APS sensor exhibited 30- and 93-fold enhanced sensitivity compared to the CNT-APS and rGO-APS sensors. This might be attributed to highly active edge sites with superior chemical reactivity, which are not present in CNT and rGO materials. Density functional theory clearly shows that the greatly enhanced gas response of GNR with edge functionalization can be attributed to the higher electron densities in the highest occupied molecular orbital levels of GNR-APS and incorporation of additional adsorption sites. This finding is the first demonstration of the importance of edge functionalization of GNR for chemical sensors.
AB - With growing focus on the use of carbon nanomaterials in chemical sensors, one-dimensional graphene nanoribbon (GNR) has become one of the most attractive channel materials, owing to its enhanced conductance fluctuation by quantum confinement effects and dense, abundant edge sites. Due to the narrow width of a basal plane with one-dimensional morphology, chemical modification of edge sites would greatly affect the electrical channel properties of a GNR. Here, we demonstrate for the first time that chemically functionalizing the edge sites with aminopropylsilane (APS) molecules can significantly enhance the sensing performance of the GNR sensor. The resulting APS-functionalized GNR has a sensitivity ((Î"R/R b ) max ) of â30% at 0.125 ppm nitrogen dioxide (NO 2 ) and an ultrafast response time (â6 s), which are, respectively, 7- and 15-fold enhancements compared to a pristine GNR sensor. This is the fastest and most sensitive gas-sensing performance of all GNR sensors reported. To demonstrate the superiority of the GNR-APS sensor, we compare its sensing performance with that of APS-functionalized carbon nanotube (CNT) and reduced graphene oxide (rGO) sensors prepared in identical synthesis conditions. Very interestingly, the GNR-APS sensor exhibited 30- and 93-fold enhanced sensitivity compared to the CNT-APS and rGO-APS sensors. This might be attributed to highly active edge sites with superior chemical reactivity, which are not present in CNT and rGO materials. Density functional theory clearly shows that the greatly enhanced gas response of GNR with edge functionalization can be attributed to the higher electron densities in the highest occupied molecular orbital levels of GNR-APS and incorporation of additional adsorption sites. This finding is the first demonstration of the importance of edge functionalization of GNR for chemical sensors.
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U2 - 10.1021/acsami.8b16688
DO - 10.1021/acsami.8b16688
M3 - Article
C2 - 30421906
AN - SCOPUS:85058138253
SN - 1944-8244
VL - 10
SP - 42905
EP - 42914
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 49
ER -