Advancements in Carbon-Based Piezoelectric Materials: Mechanism, Classification, and Applications in Energy Science.

The piezoelectric phenomenon has garnered considerable interest due to its distinctive physical properties associated with the materials involved. Piezoelectric materials, which are inherently non-centrosymmetric, can generate an internal electric field under mechanical stress, enhancing carrier separation and transfer due to electric dipole moments. While inorganic piezoelectric materials are often investigated for their high piezoelectric coefficients, they come with potential drawbacks such as toxicity and high production cost, which hinder their practical applications. Consequently, carbon-based piezoelectric materials have emerged as an alternative to inorganic materials, boasting advantages such as a large specific surface area, high conductivity, flexibility, and eco-friendliness. Research into the applications of carbon-based piezoelectric materials spans environmental remediation, energy conversion, and biomedical treatments, indicating a promising future. This review marks the first comprehensive attempt to discuss and summarize the various types of carbon-based piezoelectric materials. It delves into the underlying mechanisms by which piezoelectricity influences catalysis, biomedical applications, nanogenerators, and sensors. Additionally, various potential techniques are presented to enhance the piezoelectric performance. The design principles of representative fabrication strategies for carbon-based piezoelectric materials are analyzed, emphasizing their current limitations and potential improvements for future development. It is believed that recent advances in carbon-based piezoelectric materials will make a significant impact.