中文版本

Opportunity

The development of piezoelectric materials has long been dominated by synthetic inorganic ceramics like lead zirconate titanate (PZT), which offer high piezoelectric performance but suffer from drawbacks such as brittleness, environmental toxicity (due to lead content), and poor biocompatibility. In contrast, naturally derived biomaterials exhibit intrinsic piezoelectricity, biocompatibility, and sustainability, making them ideal for medical and wearable applications. However, existing piezoelectric biomaterials face significant challenges, including weak piezoelectric output (e.g., phage virus films with ~7.8 pm/V) and difficulty in aligning molecular dipoles to achieve uniform polarization. Traditional self-assembly methods often rely on interface-dependent processes, limiting scalability and control over film properties. This patent addresses these limitations by introducing a scalable fabrication method for bio-organic films with ceramic-like piezoelectric performance, enabling applications where flexibility, biocompatibility, and high energy conversion efficiency are critical.  

Technology

The patent discloses a novel method to fabricate piezoelectric bio-organic films by combining electric field-driven nanocrystallization and in-situ poling. The process involves:  

1. Homogeneous nucleation: Biomaterials (e.g., glycine, L-alanine) are dissolved in water and atomized into nanodroplets under an electric field (4–4.5 kV), forming nanocrystals (100–800 nm grain size) with aligned dipoles.  
2. Ceramic-like structure: The nanocrystals self-assemble into dense, polycrystalline films resembling inorganic ceramics, achieving a piezoelectric strain constant (d33 ≈ 11.2 pm/V) and voltage constant (g33 ≥ 250×10−3 V·m/N), rivaling conventional piezoceramics.  
3. In-situ electric alignment: The electric field not only facilitates nanocrystal formation but also acts as a poling mechanism to orient domains uniformly, enhancing piezoelectric response.  
4. Thermodynamic stability: The films exhibit exceptional thermal stability (no phase transition until melting at ~180°C) due to nanoconfinement effects.  

The technology is compatible with diverse substrates (silicon, plastics) and allows tunable film thickness (2–30 µm) and shape via electrohydrodynamic jet parameters.  

Advantages

• High performance: Comparable piezoelectricity to PZT ceramics (d33 up to 11.2 pm/V).  
• Biocompatibility: Safe for medical implants and wearable devices.  
• Scalability: Electric field-driven process enables wafer-scale production.  
• Thermal stability: No phase degradation below melting point (~180°C).  
• Flexibility: Tunable thickness, shape, and substrate compatibility (e.g., flexible plastics).  

Applications

• Medical devices: Implantable sensors, pacemakers, and tissue engineering scaffolds.  
• Energy harvesting: Flexible nanogenerators for self-powered electronics.  
• Wearables: Pressure-sensitive skins and health monitors.  
• Acoustics: Ultrasonic transducers for imaging or therapy.