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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. 

Abstract Recent developments in 2D magnetic materials have motivated the search for new van der Waals magnetic materials, especially Ising‐type magnets with strong magnetic anisotropy. Fe‐basedMPX₃(M= transition metal,X= chalcogen) compounds such as FePS₃and FePSe₃both exhibit an Ising‐type magnetic order, but FePSe₃receives much less attention compared to FePS₃. This work focuses on establishing the strategy to engineer magnetic anisotropy and exchange interactions in this less‐explored compound. Through chalcogen and metal substitutions, the magnetic anisotropy is found to be immune against S substitution for Se whereas tunable only with heavy Mn substitution for Fe. In particular, Mn substitution leads to a continuous rotation of magnetic moments from the out‐of‐plane direction toward the in‐plane. Furthermore, the magnetic ordering temperature displays non‐monotonic doping dependence for both chalcogen and metal substitutions but due to different mechanisms. These findings provide deeper insight into the Ising‐type magnetism in this important van der Waals material, shedding light on the study of other Ising‐type magnetic systems as well as discovering novel 2D magnets for potential applications in spintronics.