Biodegradable ferroelectric molecular crystal with large piezoelectric response

Area of Science:

• Materials Science
• Biomedical Engineering
• Crystallography

Background:

• Transient implantable piezoelectric materials are crucial for advanced biomedical applications like biosensing and drug delivery.
• Conventional piezoelectric materials often lack the required flexibility, biocompatibility, and biodegradability for in-vivo use.

Purpose of the Study:

• To identify and characterize a novel molecular crystal with high piezoelectric properties suitable for transient implantable devices.
• To evaluate the biocompatibility and biodegradability of the new material in physiological environments.

Main Methods:

• Synthesis and characterization of the molecular crystal 2,2,3,3,4,4-hexafluoropentane-1,5-diol (HFPD).
• Measurement of piezoelectric coefficients (d33 and g33) under unpoled conditions.
• Fabrication of composite films with polyvinyl alcohol.
• Assessment of biocompatibility with biological cells and biodegradation in physiological conditions.

Main Results:

• HFPD exhibits significant piezoelectricity with d33 ~138 pC/N and g33 ~2450 × 10^-3 V·m/N without poling.
• The material demonstrates good biocompatibility and desirable biodegradation and biosafety.
• Flexible piezoelectric films were created by compositing HFPD with polyvinyl alcohol, showing a d33 of 34.3 pC/N.

Conclusions:

• Molecular crystals can possess excellent piezoelectric properties, offering an alternative to traditional materials.
• HFPD is a promising candidate for developing transient implantable electromechanical devices due to its piezoelectricity, biocompatibility, and biodegradability.