Manganese optimized bismuth magnesium titanate as a high energy storage density of lead-free capacitors

As dielectric storage devices, dielectric membrane capacitors are widely used in various energy storage devices due to their high power density, medium energy density, and fast charging and discharging speeds. In this work, our team has grown high-quality and well-crystallized ferroelectric thin films xMn-BiMg
0.5
Ti
0.7
O
3
(xMn-BMT) on Pt/Ti/SiO
2
/ Si (111) substrates by sol-gel method. The crystal lattice of xMn-BMT films is distorted by the addition of trace Mn elements, resulting in a grain size reduction, which is adjusted by oxygen vacancies and other factors. The ferroelectric properties of the film are affected, and hence the energy storage properties of the film. Finally, when the Mn doping amount is x (mol%)=3, a capacitor with excellent energy storage performance is obtained. Recycled energy storage has a density of up to 92.4 J/cm
³
and an energy storage efficiency of 74.8%. This work opens a new avenue for discovering high-energy density capacitors in dielectric memory thin films.