Proton switching molecular magnetoelectricity

Abstract

The convergence of proton conduction and multiferroics is generating a compelling opportunity to achieve strong magnetoelectric coupling and magneto-ionics, offering a versatile platform to realize molecular magnetoelectrics. Here we describe machine learning coupled with additive manufacturing to accelerate the design strategy for hydrogen-bonded multiferroic macromolecules accompanied by strong proton dependence of magnetic properties. The proton switching magnetoelectricity occurs in three-dimensional molecular heterogeneous solids. It consists of a molecular magnet network as proton reservoir to modulate ferroelectric polarization, while molecular ferroelectrics charging proton transfer to reversibly manipulate magnetism. The magnetoelectric coupling induces a reversible 29% magnetization control at ferroelectric phase transition with a broad thermal hysteresis width of 160 K (192 K to 352 K), while a room-temperature reversible magnetic modulation is realized at a low electric field stimulus of 1 kV cm−1. The findings of electrostatic proton transfer provide a pathway of proton mediated magnetization control in hierarchical molecular multiferroics.

Releasing chemical energy in spatially programmed ferroelectrics

“…For high-throughput screening of integrated molecular energetic ferroelectrics 8 , 22 , a two-step machine learning technique is applied. As shown in Supplementary Fig.…”

“…Energetic materials used in this study comes from Huang and Massa 37 and Mathieu 36 containing 109 and 307 compounds respectively. The ferroelectric materials 8 come from of which the detonation velocity for three ferroelectric materials are known 6 , 38 , 39 . We use three random train/test splits of 2/1 from among the smaller set of three ferroelectric materials with known detonation velocity values, while keeping the entire set of energetic materials to train the machine learning models.…”

Magnetoelectric interaction in molecular multiferroic nanocomposites

“…1 Some of the potential applications of multiferroic materials include microwave devices, 2,3 energy harvesting, and memory storage devices. 4,5 Molecular ferroic materials 6,7 have the exibility of incorporating their structures 8 for exploring new compositions that demonstrate coupling between electric and magnetic responses. [9][10][11] One of the challenges in the path of achieving molecular multiferroic is incorporating suitable ferromagnetic and ferroelectric materials together in such a way that both phases exist simultaneously under the specic temperature, particularly room-temperature multiferroic orders.…”

“…The achieved substance with a dark blue color is dried for one day in a vacuum chamber at room temperature. 7,22 The product is a dark blue powder of PB nanocrystals. Since the PB powder is sensitive to oxidation, it is necessary to be kept in the glove box.…”

“…1 Some of the potential applications of multiferroic materials include microwave devices, 2,3 energy harvesting, and memory storage devices. 4,5 Molecular ferroic materials 6,7 have the flexibility of incorporating their structures 8 for exploring new compositions that demonstrate coupling between electric and magnetic responses. 9–11…”