Choi, H.; Pattipaka, S.; Son, Y.H.; Bae, Y.M.; Park, J.H.; Jeong, C.K.; Lee, H.E.; Kim, S.-D.; Ryu, J.; Hwang, G.-T. Improved Energy Storage Density and Efficiency of Nd and Mn Co-Doped Ba0.7Sr0.3TiO3 Ceramic Capacitors Via Defect Dipole Engineering. Materials2023, 16, 6753.
Choi, H.; Pattipaka, S.; Son, Y.H.; Bae, Y.M.; Park, J.H.; Jeong, C.K.; Lee, H.E.; Kim, S.-D.; Ryu, J.; Hwang, G.-T. Improved Energy Storage Density and Efficiency of Nd and Mn Co-Doped Ba0.7Sr0.3TiO3 Ceramic Capacitors Via Defect Dipole Engineering. Materials 2023, 16, 6753.
Choi, H.; Pattipaka, S.; Son, Y.H.; Bae, Y.M.; Park, J.H.; Jeong, C.K.; Lee, H.E.; Kim, S.-D.; Ryu, J.; Hwang, G.-T. Improved Energy Storage Density and Efficiency of Nd and Mn Co-Doped Ba0.7Sr0.3TiO3 Ceramic Capacitors Via Defect Dipole Engineering. Materials2023, 16, 6753.
Choi, H.; Pattipaka, S.; Son, Y.H.; Bae, Y.M.; Park, J.H.; Jeong, C.K.; Lee, H.E.; Kim, S.-D.; Ryu, J.; Hwang, G.-T. Improved Energy Storage Density and Efficiency of Nd and Mn Co-Doped Ba0.7Sr0.3TiO3 Ceramic Capacitors Via Defect Dipole Engineering. Materials 2023, 16, 6753.
Abstract
In this paper, we investigate the structural, microstructural, dielectric, and energy storage properties of Nd and Mn co-doped Ba0.7Sr0.3TiO3 [(Ba0.7Sr0.3)1-xNdxTi1-yMnyO3 (BSNTM) ceramics (x = 0, 0.005, and y = 0, 0.0025, 0.005, and 0.01)] via a defect dipole engineering method. The complex defect dipoles (MnTi"-VO∙∙)∙ and (MnTi"-VO∙∙) between acceptor ions and oxygen vacancies capture electrons, enhancing the breakdown electric field and energy storage performances. XRD, Raman spectroscopy, and microscopic investigations of BSNTM ceramics revealed the formation of a tetragonal phase, increased oxygen vacancies, and reduced grain size with Mn dopant, respectively. The BSNTM ceramics with x=0.005 and y=0 exhibit a high dielectric constant of 2058 and a dielectric loss of 0.026 at 1 kHz. These values gradually decreased to 1876 and 0.019 for x=0.005 and y=0.01 due to the Mn2+ ions at Ti4+-site, which facilitates the formation of oxygen vacancies, and prevents the decrease of Ti4+. In addition, the defect dipoles act as a driving force for depolarization to tailor the domain formation energy and domain wall energy, which provides a high difference between the maximum polarization of Pmax and remnant polarization of Pr (ΔP=10.39 µC/cm2). Moreover, the complex defect dipoles with optimum oxygen vacancies in BSNTM ceramics can provide not only a high ΔP but also reduce grain size, which together improve the breakdown strength from 60.4 to 110.6 kV/cm, giving rise to a high energy storage density of 0.41 J/cm3 and high efficiency of 84.6% for x=0.005 and y=0.01. These findings demonstrate that defect dipoles engineering is an effective method to enhance the energy storage performance of dielectrics for capacitor applications.
Keywords
Ceramic capacitors; Donor-acceptor complex; Defect dipole engineering; Dielectric and ferroelectric properties; Energy storage density and efficiency
Subject
Engineering, Other
Copyright:
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