Search for: All records

Abstract Recently, layered transition metal thiophosphate MPX₃(M= transition metals,X= S or Se) have gained significant attention because of their rich magnetic, optical, and electronic properties. Specifically, the diverse magnetic structures and the robustness of magnetism in the two-dimensional (2D) limit have made them prominent candidates to study 2D magnetism. Numerous efforts such as substitutions and interlayer intercalations have been adopted to tune the magnetic properties of these materials, which has greatly deepened the understanding of the underlying mechanisms that govern the properties. In this work, we focus on modifying the magnetism of Ising-type antiferromagnet FePS₃using electrochemical lithium intercalation. Our work demonstrate the effectiveness of electrochemical intercalation as a controllable tool to modulating magnetism, including tuning magnetic ordering temperature and inducing low temperature spin-glass state, offering an approach for implementing this material into applications. 

Abstract Antiferromagnetic van der Waals‐typeM₂P₂X₆compounds provide a versatile material platform for studying 2D magnetism and relevant phenomena. Establishing ferromagnetism in 2D materials is technologically valuable. Though magnetism is generally tunable via a chemical way, it is challenging to induce ferromagnetism with isovalent chalcogen and bimetallic substitutions inM₂P₂X₆. Here, we report co‐substitution of Cu¹⁺and Cr³⁺for Ni²⁺in Ni₂P₂S₆, creating Cu_xNi_2(1‐x)Cr_xP₂S₆medium‐entropy alloys spanning a full substitution range (x= 0 to 1). Such substitution strategy leads to a unique evolution in crystal structure and magnetic phases that are distinct from traditional isovalent bimetallic doping, with Cu and Cr co‐substitution enhancing ferromagnetic correlations and generating a weak ferromagnetic phase in intermediate compositions. This aliovalent substitution strategy offers a universal approach for tuning layered magnetism in antiferromagnetic systems, which along with the potential for light‐matter interaction and high‐temperature ferroelectricity, can enable multifunctional device applications. 

Two‐dimensional ferromagnets are highly attractive for spintronic applications and chromium–telluride compounds form one of the most diverse families in this field. While the layered 1T‐CrTe₂has been studied extensively for its high Curie temperature, strong anisotropy, and large magnetic moments, its parent compound KCrTe₂has received almost no systematic attention. Large crystals of KCrTe₂were grown by solid‐state methods. Large 1T‐CrTe₂crystals were obtained via deintercalation of K from KCrTe₂. KCrTe₂exhibited an antiferromagnetic transition around 87 K, which resides between LiCrTe₂and NaCrTe₂. The chemical process from KCrTe₂to 1T‐CrTe₂was studied by static studies. The complete removal of K within KCrTe₂helps make 1T‐CrTe₂easy fabrication of large thin flakes (the easy‐peel 1T‐CrTe₂), which were studied using ferromagnetic resonance spectroscopy (FMR). FMR was employed to study the magnetization dynamics of 1T‐CrTe₂crystals, which verified that 1T‐CrTe₂crystals exhibited ferromagnetic response at room temperature.