Magnetic and luminescent lanthanoid (Ln = Tb, Dy) 2D MOFs on functionalized silicon

Abstract

The controlled deposition of organized molecular materials on technologically relevant substrates is crucial for the development of innovative magneto-optical devices. In this work, we report the growth of lanthanoid-based 2D metal–organic frameworks (MOFs) with formula unit [Ln(MeCOO)(PhCOO)₂] (Ln = Dy, Tb) on Si(100) wafers functionalized by silanization. The thickness, morphology and composition of the grown material was assessed using a combination of ellipsometry, contact angle measurements, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The on-surface grown terbium 2D MOFs exhibit green luminescence, like the bulk. Furthermore, chemisorbed Dy and Tb 2D MOFs retain a significant magnetic moment, as demonstrated by X-ray magnetic circular dichroism (XMCD) measurements conducted at the M_4,5 edge of the two lanthanoids. Our work paves the way for the preparation of magneto-optical devices and organized arrays of single-molecule magnets (SMMs) and qubits on surfaces for high-density information storage and quantum computing applications.