Constructing core-shell structured BaTiO3@carbon boosts piezoelectric activity and cell response of polymer scaffolds

Piezoelectric composites have shown great potential in constructing electrical microenvironment for bone healing since their integration of polymer flexibility and ceramic piezoelectric coefficient. Herein, core-shell structured BaTiO3@carbon (BT@C) hybrid nanoparticles were prepared by in situ oxidative selfpolymerization and template carbonization. Then the BT@C was introduced into polyvinylidene fluoride (PVDF) scaffolds manufactured by selective laser sintering. On one hand, the carbon shell could strengthen the local electric field loaded on BT in poling process owing to it served as a diffusion layer to provide space for charge transfer and accumulation. In this case, more electric domain within BT would be aligned along the polarization field direction and thus promoted the paly of BT's piezoelectric activity. On the other hand, the carbon shell could induce the formation of beta phase due to the sp2 hybrid-bonded carbon atoms in carbon shell forming electrostatic interaction with hydrogen atoms in PVDF chains, which further enhanced the piezoelectric response of the scaffolds. Results showed that the scaffold presented augmented piezoelectric performance with output voltage of 5.7 V and current of 79.8 nA. The improved electrical signals effectively accelerated cell proliferation and differentiation. Furthermore, the scaffold displayed improved mechanical performance due to rigid particle strengthen effect.

Automated summary

Piezoelectric composites incorporating BaTiO3@carbon (BT@C) hybrid nanoparticles show enhanced piezoelectric performance and mechanical properties, accelerating cell proliferation and differentiation. The carbon shell strengthens the local electric field loaded on BT and induces the formation of beta phase, enhancing the piezoelectric response of the scaffolds.