Self-powered light dimming system using a magneto-mechano-electric generator with hardener-doped Pb(Mg_1/3Nb_2/3)O₃-Pb(Zr,Ti)O₃ single crystals

In this study, Pb(Mg_1/3Nb_2/3)O₃-Pb(Zr,Ti)O₃ (PMN-PZT) single crystals were doped with hardener Mn at variable concentrations to fabricate a high-output magneto-mechano-electric (MME) generator. The dielectric constant and dielectric loss (tan δ) of the PMN-PZT crystal were gradually decreased by doping with 0 to 0.8 mol% hardener Mn acceptor. Owing to the low energy loss and enhanced energy conversion properties of the Mn-doped hard-type PMN-PZT, the MME generator achieved an improved magnetoelectric coefficient of 783.09 V per cm·Oe, and the corresponding mechanical quality factor was 315 at 0.8 mol% Mn under resonance frequency operation conditions. The Mn-modified MME device can generate a root mean square output power of 3.3 mW when an alternating current magnetic field of 8 Oe is applied, which is ∼1.8 times higher than that of the MME generator fabricated without Mn-doping. Finally, the electric power of the hard-type PMN-PZT MME generator was directly utilized to produce a self-powered light dimming system composed of an MME harvester, an energy conversion circuit, a CdS ambient light sensor, and a light-emitting diode.