Influence of Mn Ions’ Insertion in Pseudo-Tetragonal Phased CaBi(4)Ti(4)O(15)-Based Ceramics for Highly Efficient Energy Storage Devices and High-Temperature Piezoelectric Applications

In the present era of advanced technology, the surge for suitable multifunctional materials capable of operating above 300 °C has increased for the utilization of high-temperature piezoelectric devices. For this purpose, a pseudo-tetragonal phased CaBi(4)Ti(3.98) (Nb(0.5)Fe(0.5))(0.02)O(15):xwt%MnO(2) (CBTNF:xMn), with x = 0–0.20, ceramic system has been engineered for the investigation of structural, ferroelectric, dielectric and high-temperature-dependent piezoelectric properties. XRD analysis confirms that low-content Mn-ion insertion at the lattice sites of CBTNF does not distort the pseudo-tetragonal phase lattice of CBTNF:xMn ceramics, but enhances the functional behavior of the ceramic system, specifically at x = 0.15 wt%Mn. Compared to pure CBT and CBTNF ceramics, CBTNF:0.15Mn has demonstrated a highly dense relative density (~96%), a saturated polarization (P(S)) of 15.89 µC/cm(2), a storage energy density (W(ST)) of ~1.82 J/cm(3), an energy-conversion efficiency (ƞ) of ~51% and an upgraded piezoelectric behavior (d(33)) of 27.1 pC/N at room temperature. Sharp temperature-dependent dielectric constant (ε(r)) peaks display the solid ferroelectric behavior of the CBTNF:0.15Mn sample with a Curie temperature (T(C)) of 766 °C. The thermally stable piezoelectric performance of the CBTNF:0.15Mn ceramic was observed at 600 °C, with just a 0.8% d(33) loss (25 pC/N). The achieved results signify that multi-valence Mn ions have effectively intercalated at the lattice sites of the pseudo-tetragonal phased CBTNF counterpart and enhanced the multifunctional properties of the ceramic system, proving it to be a durable contender for utilization in energy-storage applications and stable high-temperature piezoelectric applications.