Current Status and Prospects of Additive Manufacturing of Flexible Piezoelectric Materials

As a kind of important functional materials, flexible piezoelectric materials have the advantages of good toughness, high plasticity and light-weight.The flexible piezoelectric materials can realize the effective conversion between mechanical energy and electrical energy, and it can be attached to the human body to obtain human or environment information in real time, thereby widely used in motion detection, health monitoring, and human computer interaction.With the high requirements of various there dimensional (3D) structures of flexible piezoelectric materials, additive manufacturing has been extensively utilized to fabricate different kinds of piezoelectric materials.Fortunately, this technology is expected to break the bottleneck of traditional processing of piezoelectric material by improving the structural design freedom and piezoelectric performance of flexible piezoelectric materials.Thus, the emergence of additive manufacturing printing technology provides enormous potential and opportunities for the application of flexible piezoelectric materials.Based on the introduction of the classification and performance of flexible piezoelectric materials, this paper systematically explained the main additive manufacturing technologies, including fused deposition modeling, direct ink writing, selective laser sintering, electric-assisted direct writing, stereolithography, and inkjet printing.In thefollowing, the structural designs of flexible piezoelectric materials produced by different additive manufacturing approaches were summarized, such as multi-layer structure, porous structure, and interdigital structure.Moreover, the applications of flexible piezoelectric materials produced by additive manufacturing were systematically introduced in fields of energy harvesting, piezoelectric sensing, human computer interaction, bioengineering.Finally, the challenges faced by additive manufacturing of flexible piezoelectric materials and the development trends in the future were summarized and prospected.