Heterometallic 3d-4f Alkoxide Precursors for the Synthesis of Binary Oxide Nanomaterials.

In this study, a new method for the synthesis of heterometallic 3d-4f alkoxides by the direct reaction of metallic lanthanides (La, Pr, Nd, Gd) with MCl (M = Mn, Ni, Co) in 2-methoxyethanol was developed. The method was applied to the synthesis of the heterometallic oxo-alkoxide clusters [LnMn(μ-O)(μ-OR)(HOR)Cl] (Ln = La (), Nd (), Gd (); = 0, 2, 4); [PrM(μ-O)(μ-OR)(HOR)Cl] (M = Co (), Ni (); = 2, 4); and [LnMn(μ-OH)(μ-OR)(μ-OR)(μ-Cl)(HOR)Cl] (Ln = La () and Pr ()). Mechanistic investigation led to the isolation of the homo- and heterometallic intermediates [Pr(μ-OR)(μ-Cl)(HOR)Cl] (), [Co(μ-OR)(HOR)Cl] (), [Ni(μ-OR)(HOEt)Cl] (), [Mn(μ-OR)(HOR)(HOEt)Cl] (), and [Nd(HOR)Cl][CoCl] (). In the presence of an external M(II) source at 1100 °C, - and were selectively converted into binary metal oxide nanomaterials with trigonal or orthorhombic perovskite structures, i.e., LaMnO, GdMnO, NdMnO, PrMnO, and PrCoO. Compound decomposed into a mixture of homo- and heterometallic oxides. The method presented provides a valuable platform for the preparation of advanced heterometallic oxide materials with promising magnetic, luminescence, and/or catalytic applications.