TY - GEN
T1 - Temperature dependent thermopower and resistance measurements of CNT-MgB2 composites
AU - Adu, Kofi W.
AU - Jayasingha, Ruwantha
AU - Ma, Danhao
AU - Sumanasekera, Gamini U.
PY - 2012
Y1 - 2012
N2 - The temperature dependent resistance R(T) and thermopower S(T) of sintered single wall carbon nanotubes (SWCNT) and magnesium diboride (MgB2) composites containing 5wt%, 10wt%, and 15wt% of SWCNTs have been measured and compared to their pure counterparts. The thermopower of both MgB2 (in the normal state) and SWCNT remain positive over the entire temperature range (10K to 300K) with room temperature values being ∼ 8μV/K and 57μV/K, respectively. The thermopower of the sintered composites decreased with decreasing temperature and switched from positive to negative near 70K. The superconducting critical temperature (Tc) of the samples ranges from 38K-41K. The room-temperature resistance ratio (RRR) is seen to depend on the sample composition. The temperature width (ΔT) is observed to increase with increasing SWCNT concentration. The normal state resistance data were fitted with the generalized Block-Grüneisen function obtaining Debye temperature of ∼ 900K.
AB - The temperature dependent resistance R(T) and thermopower S(T) of sintered single wall carbon nanotubes (SWCNT) and magnesium diboride (MgB2) composites containing 5wt%, 10wt%, and 15wt% of SWCNTs have been measured and compared to their pure counterparts. The thermopower of both MgB2 (in the normal state) and SWCNT remain positive over the entire temperature range (10K to 300K) with room temperature values being ∼ 8μV/K and 57μV/K, respectively. The thermopower of the sintered composites decreased with decreasing temperature and switched from positive to negative near 70K. The superconducting critical temperature (Tc) of the samples ranges from 38K-41K. The room-temperature resistance ratio (RRR) is seen to depend on the sample composition. The temperature width (ΔT) is observed to increase with increasing SWCNT concentration. The normal state resistance data were fitted with the generalized Block-Grüneisen function obtaining Debye temperature of ∼ 900K.
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U2 - 10.1557/opl.2012.705
DO - 10.1557/opl.2012.705
M3 - Conference contribution
AN - SCOPUS:84870367608
SN - 9781605113845
T3 - Materials Research Society Symposium Proceedings
SP - 123
EP - 128
BT - Carbon Nanotubes, Graphene and Related Nanostructures
T2 - 2011 MRS Fall Meeting
Y2 - 28 November 2011 through 2 December 2011
ER -