Replacing Ag TS SCH 2 -R with Ag TS O 2 C-R in EGaIn-Based Tunneling Junctions Does Not Significantly Change Rates of Charge Transport

Abstract

This paper compares rates of charge transport by tunneling across junctions with the structures AgTSX(CH2)2nCH3 //Ga2O3 /EGaIn (n=1–8 and X= [BOND]SCH2[BOND] and [BOND]O2C[BOND]); here AgTS is template-stripped silver, and EGaIn is the eutectic alloy of gallium and indium. Its objective was to compare the tunneling decay coefficient (β, Å−1) and the injection current (J0, A cm−2) of the junctions comprising SAMs of n-alkanethiolates and n-alkanoates. Replacing AgTSSCH2-R with AgTSO2C-R (R=alkyl chains) had no significant influence on J0 (ca. 3×103 A cm−2) or β (0.75–0.79 Å−1)—an indication that such changes (both structural and electronic) in the AgTSXR interface do not influence the rate of charge transport. A comparison of junctions comprising oligo(phenylene)carboxylates and n-alkanoates showed, as expected, that β for aliphatic (0.79 Å−1) and aromatic (0.60 Å−1) SAMs differed significantly.