Hydroxyapatite‐barium titanate piezocomposites with enhanced electrical properties

Abstract

The present work aims to obtain Hydroxyapatite (HA) ‐ Barium Titanate (BT) piezocomposites with improved electrical properties by retaining OH− ions and tuning BT grain size. Dense piezocomposites of HA‐BT were obtained, using single step Spark Plasma Sintering. The presence of OH− ions in the sintered piezocomposites of HA‐BT was confirmed by thermal characterization and Fourier transform infrared transmittance. No decomposition/interaction between HA and BT phases were observed in the complete range of temperature studied. The dielectric and pyroelectric properties were studied as a function of temperature (100 K to 450 K) and frequency (100 Hz to 2 MHz). The influence of the ferroelectric grain size (300 and 500 nm) on the electrical properties of HA‐BT has been analyzed. The dielectric permittivity of HA‐BT ceramics can be enhanced with appropriate ferroelectric grain size and volume fraction of BT (<80%).

Novel Lead-free biocompatible piezoelectric Hydroxyapatite (HA) – BCZT (Ba0.85Ca0.15Zr0.1Ti0.9O3) nanocrystal composites for bone regeneration

“…However, the piezoelectricity associated with human bone tissue in vivo is ascribed to its composition that produces biological electricity due to the ionic displacement under a deformation force [8][9][10]. Since the OH groups in HA were found to be responsible for the reported piezoelectric activity, the retention of these polar groups is essential for observing spontaneous polarization [11,12]. The available literature confirms that the reorientation of polar groups in HA leads to the cell growth in HA implants [13].…”

Smart Injectable Self-Setting Monetite Based Bioceramics for Orthopedic Applications

“…The results showed accelerated bone formation kinetics around HA–BT implants as compared to pure HA [ 15 ]. Progressing along the same strategical avenue, Dubey et al and Prakasam et al fabricated BT infused HA composites via multi and single-stage spark plasma sintering (SPS) respectively and the results yielded good biomechanical and electrical properties [ 16 , 17 ]. Furthermore, when surface charge was generated by electrical poling of such composites, higher cell proliferation was observed on the negatively charged surfaces [ 18 ].…”

Dual response of osteoblast activity and antibacterial properties of polarized strontium substituted hydroxyapatite—Barium strontium titanate composites with controlled strontium substitution

“…Contrasting reports have been published on osteoblast and osteoclast activities on polarized HA surfaces. For example, some studies have showed improved osteoblast activity on positively charged surfaces, with other work has indicated better activity on negatively charged surfaces 20,21 …”