Confirmation of the Rectifying Behavior in a Pentacoordinate [N2O2] Iron(III) Surfactant Using a "Eutectic Galn vertical bar LB Monolayer vertical bar Au" Assembly
Examples of coordination compounds that act as molecular rectifiers are rare. Recently a pentacoordinate [N2O2] Fe(III) surfactant, namely [Fe-III(L-N2O2)-Cl] (I), was studied as a Langmuir-Blodgett (LB) monolayer between two Au electrodes, "Au vertical bar LB1 vertical bar Au". Rectification was observed, but only at low currents. In order to verify the current rectification of this species, a new setup is used, where an LB monolayer of 1 is placed between Au and a soft contact of gallium indium eutectic (EGaIn), as the "sandwich" "EGaIn/Ga2O3 vertical bar LB1 vertical bar Au". When scanned from 0 to -1.5 V, 90% of the sandwiches remained stable, while scanning from 0 to + 1.5 V only 10% remained stable. For the scan range of +/- 0.7 V, 90% of the sandwiches were stable on the first scan; about half of them could withstand repeated scans; the rectification ratios (RR) at 0.7 V ranged between 3 and 12. Pushing the bias range to +/- 1.0 V, the RR increased to between 50 and 150, but the sandwiches lasted for at most three full scans.
