Room Temperature Giant Magnetoelectric Coupling in {Co III 3 Dy III } Molecular Single Crystal Derived Nanogenerator

Magnetoelectric (ME) materials are sought for next-generation memory, spintronics, and energy harvesting, but strong ME coupling at room temperature (RT) in single-phase systems remains rare due to the mutual exclusivity of ferroelectricity and ferromagnetism in conventional oxides. While molecular magnetoelectrics offer synthetic tunability and multifunctionality, achieving robust ME coupling above RT is still a much-coveted target. Here, we show that a homochiral molecular complex, [Co III 3 Dy III (L1) 6 ]·4MeOH ( Co 3 Dy ), exhibits a record ME coupling coefficient of 250 mV cm –1 Oe –1 at RT, enabled by magnetostriction–piezoelectric coupling. An ME nanogenerator fabricated with single crystals of Co 3 Dy generates a 430 mV output voltage and 0.3 μA current under a 24.2 Oe AC magnetic field, demonstrating its exceptional ME response. This work establishes single-phase molecular complexes as promising candidates for practical ME devices.