Anchoring Cu(II)-based Low-Dimensional S=1/2 Spin Lattices onto Functionalized Graphene

Abstract

Magnetic materials with spins restricted in low-dimensions provide an intriguing platform to study spin interactions. Coupled with geometric frustration (for example, Kagome lattice), long-range magnetic ordering is suppressed in low-dimensional magnets, offering unconventional magnetic ground states with emergence of quantum effects (quantum spin liquids). Here, we have anchored some representative Cu(II)-based low-dimensional S=1/2 spin lattices onto semiconducting functionalized graphene – reduced graphene oxide (rGO) – via in-situ oxidation-reduction reaction involving Cu(I) salts and graphene oxide (GO) as primary precursors. The magnetic signatures of insulating Cu(II)-based S=1/2 spin lattices, explored here, were significantly influenced by the diamagnetic and semiconducting rGO in the respective nanocomposites, thereby generating a new class of magnetic semiconductors. Specifically, we were able to embed exotic S=1/2 spin lattices of Cu(II) namely, clinoatacamite, barlowite, paratacamite, herbertsmithite, and botallackite from the atacamite family of minerals onto rGO matrix. rGO-atacamite systems presented here can be explored further by studying magnetic field dependent electrical transport characteristic as well as electric field dependent magnetic response for possible spintronic applications.