Structural diversity dependent cation incorporation into magnetic Cr–Se nanocrystals

Abstract

Chromium selenide (Cr–Se)-based low-dimensional materials have attracted significant attention in spintronics because of their diverse structure- and composition-dependent magnetic properties. While significant progress has been made in fabricating the Cr–Se family of nanomaterials through techniques like chemical vapor deposition, the synthesis of Cr–Se nanocrystals (NCs) via colloidal methods remains underexplored. In this work, we demonstrate the robust colloidal synthesis approach for producing Cr₂Se₃ and Cr₃Se₄ NCs with distinct morphologies by varying the Cr precursors and ligands. Cr–Se NCs can serve as templates for cation exchange (CE) reactions involving monovalent Cu⁺ and Ag⁺, divalent Zn²⁺ and Cd²⁺, and trivalent In³⁺, facilitating the creation of a diverse library of metal selenide NCs and nanoheterostructures. Our findings highlight how the outcomes of CE reactions are influenced by the structure of various Cr–Se phases. Furthermore, the magnetic properties of the as-synthesized Cr–Se NCs and their derivative CuCrSe₂ were investigated. Our work provides a robust synthesis route for the Cr–Se class of magnetic nanomaterials and a platform for creating a diverse range of functional metal selenide NCs via CE reactions.