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Updated: May 22, 2025

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
On-Off Magnetism of Ferromagnetic Metals via Electrochemical Driven Band Filling
Zeyuan Bu1, Xiang Li1, Leqing Zhang1
1College of Physics, Weihai Innovation Research Institute, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China.
Abstract:
Ferromagnetic metals, distinguished by high Curie temperatures and magnetization, are crucial in voltage-controlled magnetism for potential room-temperature applications in low-power multifunctional devices. Despite numerous attempts based on various mechanisms, achieving ideal magnetic modulation in metals remains challenging. This work proposes a new mechanism to control bulk metal magnetism by modulating valence electron filling in spin-polarized bands, leveraging the Slater-Pauling rule in alloys. Fully reversible on-off switching of ferromagnetism is realized in a 70 nm thick Sn-Co alloy film, with a modulation amplitude approaching 40 emu g-1 within 1.5 V. Operando magnetometry demonstrates superior magnetic modulation with nonvolatility, robust durability with rapid response. Furthermore, this strategy exploits band filling by a nonmagnetic metal's valence electrons during alloying, showcasing universality confirmed by significant magnetic switching in Sb-Co and Sn-Fe alloys. These results introduce a novel magnetic modulation method in bulk metals and, crucially, suggest a versatile and straightforward design paradigm for magnetic manipulation.
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