A novel structure design of barium strontium titanate piezoelectric coating on titanium surface enhanced its response to low-intensity pulsed ultrasound

The piezoelectric effect was an electromechanical conversion effect that can accelerate the bone repair process, relying on mechanical forces for excitation. The design of a piezoelectric coating on titanium alloy surface that can respond to small loads was an urgent problem to be solved for its application in bone repair. In this work, a strontium barium titanate rod array coating was prepared on titanium surface by designing the microstructure and composition. The formation mechanism of barium strontium titanate array structure was analyzed. The barium strontium titanate rod array coating represented excellent piezoelectric properties. The surface potential distribution of barium strontium titanate rod with different conditions was simulated. Interestingly, the surface potential distribution results of the barium strontium titanate rod array showed that the positive and negative potential were distributed simultaneously, which was further confirmed by mineralization results. The strontium barium titanate rod array coating showed no toxicity to osteoblasts. The coating surface was covered by osteoblasts after 5 days of co-culture, which showed good osteoblast proliferation and adhesion. The research results will provide data support and research ideas for the clinical application of biological piezoelectric coatings on titanium and titanium alloys surface. •A BST rod array structure coating on titanium surface was designed.•The crystallographic formation mechanism of rod array structure was analyzed.•The influencing factors of potential distribution on rod array were elucidated.•The piezoelectric effect of the coating was excited by low-intensity pulsed ultrasound.