Epitaxial Electrodeposition of Prussian Blue Thin Films on Single-Crystal Au(110)

Epitaxial Prussian blue (PB) films are deposited electrochemically onto a Au(110) substrate. High-resolution X-ray diffraction shows that the PB films have a [111] out-of-plane orientation. The very large lattice mismatch of 148% is reduced to about 1% by the formation of (1 × 2)PB(111)[↑10]//(6 × 5)Au(110)[↑10] and (1 × 2)PB(111)[01↑]//(6 × 5)Au(110)[↑10] epitaxial relationships. Peaks in the cyclic voltammogram of PB on Au(110) are sharper than those on polycrystalline Au, consistent with higher structural order and a single out-of-plane orientation. The development of epitaxial films of PB and PB analogues will allow the measurement of the orientation-dependent properties of these molecular magnets. It will also open the door to the development of novel molecular spintronic devices, such as those which exhibit spin-dependent electron transfer. Copyright © 2003 American Chemical Society.