Nanoporous Composites With Converse Magnetoelectric Effects for Energy-Efficient Applications

New materials, based on nanoporous magnetic frameworks filled with liquid or solid dielectric phases, are overviewed. Due to their large surface area, these materials exhibit enhanced magnetoelectric effects (i.e., control of magnetism with voltage) compared to archetypical multiferroic heterostructures. The nanoporous magnetic films can either be metallic, oxides, or a mixture of metal and metal-oxide phases. When these composites are subjected to voltage, different magnetoelectric mechanisms can occur: Electric surface charging, strain-mediated coupling, or ion migration (magneto-ionics). Drastic changes in coercivity and magnetization are often observed, making these materials appealing for technological fields such as spintronics, magnetic sensors/actuators, or memories.