Mn doping to enhance energy storage performance of lead-free 0.7NBT-0.3ST thin films with weak oxygen vacancies

Abstract

In this study, we present an effective strategy to enhance energy-storage density by the Mn2+ substitution of Ti4+ into 0.7(Na0.5Bi0.5)TiO3-0.3SrTiO3 (0.7NBT-0.3ST) relaxor ferroelectric thin films. The influence of Mn doping on the microstructures, ferroelectric properties, and energy-storage performances of the as-prepared films was investigated in detail. The results show that the values of electric break-down field strength and the difference values between maximum polarization and remnant polarization of the thin films are markedly improved by appropriate Mn doping. Owing to the high break-down field strength of 1894 kV/cm and the huge difference value between the maximum polarization and the remnant polarization of 56 μC/cm2, a giant recoverable energy-storage density of 27 J/cm3 was obtained for the 1 mol. % Mn-doped 0.7NBT-0.3ST thin film. These results indicate that the appropriately Mn-doped 0.7NBT-0.3ST thin films are promising for the application of advanced capacitors with high-energy storage density.

Large recoverable energy density with excellent thermal stability in Mn‐modified NaNbO3‐CaZrO3 lead‐free thin films

“…These results suggest that 1 mol% Mn‐doped NNCZ thin films possess good frequency stability of the energy storage performance. Notably, the large W r value and excellent thermal stability of our 1 mol% Mn‐doped NNCZ thin film is highly comparable with those of other lead‐free thin films prepared by sol‐gel method, as given in Table . Most importantly, we believe that there is still plenty of room for improving the energy storage performance of NNCZ systems.…”

Dielectric films for high performance capacitive energy storage: multiscale engineering

“…4d). 62 Since P D reacts relatively more slowly to electric field, it offers a restoring force for P s to switch back to its original orientation, causing an ageing feature that is characteristic with a pinched P-E loop and a much suppressed P r (Fig. 4e).…”

Electrical properties of calcium doped BiFeO3 films on LaNiO3 coated Pt substrates

“…These two transport mechanisms are very similar and can be distinguished from the slope measured from the straight line region of the current-voltage (I-V) curve in the form of a ln J vs ln E plot. According to literature data [31], the curves of all films can be modelled in terms of space charge-limited current (SCLC).Once in the low field region, the curves follow ohmic conduction properties (α ∼ 1).With the increase in electric field, a change in α takes place, in When the electric field is further increased, a sharp increase in the slope occurs because of more complex conduction mechanisms. The change in the transition electric field region corresponding to the conduction mechanism may be due to the electrode interface traps, grain boundary defects and oxygen vacancies.…”

“…Although the reason behind the occurrence of FM in the Ca-doped BFO samples is not clearly understood, this can be attributed to the change in interaction between Fe + 3 and Fe + 4 breaking down the balance between the antiparallel sublattice magnetization [43]. Change in canting angle [44] or spiral spin modulation [31] may also be responsible for this phenomenon.…”