College of Materials Science and Engineering, Sichuan University, Chengdu 610064, China.
Sichuan Province Key Laboratory of Information Materials, Southwest Minzu University, Chengdu, 610041, P. R. China.
Mater Horiz. 2022 Aug 1;9(8):2180-2190. doi: 10.1039/d2mh00437b.
Implantable medical electronics (IMEs) are now becoming increasingly prevalent for diagnostic and therapeutic purposes. Despite extensive efforts, a primary challenge for IMEs is reliable wireless power and communication to provide well-controlled, therapeutically relevant effects. Ultrasonic energy transfer and communication (UETC) employing traveling ultrasound waves to transmit energy has emerged as a promising wireless strategy for IMEs. Nevertheless, conventional UETC systems are rigid, bulky, and based on toxic lead-based piezoelectric materials, raising efficiency and safety concerns. Here, we present a novel transcutaneous UETC system based on a two-dimensional flexible lead-free piezoelectric array (f-LFPA) that hybridizes high-performance (piezoelectric coefficient ≈ 503 pC N) (K,Na)NbO-based eco-friendly piezo-units with soft structural components. The newly developed lead-free piezo-unit exhibits submicron ferroelectric domains and superior energy harvesting figures of merit ( ≈ 20 000 × 10 m N), resulting in the prepared f-LFPA demonstrating a high output voltage of 22.4 V, a power density of 0.145 W cm, and a signal-to-noise ratio of more than 30 dB within the FDA safety limits, while maintaining the flexibility for wide-angle receiving. Further experiment demonstrates the adequate power supply capabilities of the f-LFPA and its possible application in future implantable eco-friendly bioelectronics for diagnostics, therapy, and real-time monitoring.
可植入医疗电子设备（IMEs）现在越来越多地用于诊断和治疗目的。尽管进行了广泛的努力，但 IMEs 的一个主要挑战是可靠的无线电源和通信，以提供良好控制的、治疗相关的效果。利用传播超声波传输能量的超声能量传输和通信（UETC）已经成为 IMEs 的一种有前途的无线策略。然而，传统的 UETC 系统是刚性的、庞大的，并且基于有毒的含铅压电材料，这引发了效率和安全方面的问题。在这里，我们提出了一种基于二维柔性无铅压电阵列（f-LFPA）的新型经皮 UETC 系统，该系统将高性能（压电系数≈503 pC N）（K，Na）NbO 基环保压电单元与软结构组件相结合。新开发的无铅压电单元具有亚微米级的铁电畴，并且具有卓越的能量收集优值（≈20,000×10 m N），从而使制备的 f-LFPA 展示出 22.4 V 的高输出电压、0.145 W cm 的功率密度和超过 30 dB 的信噪比，同时保持了宽角度接收的灵活性。进一步的实验证明了 f-LFPA 的充足供电能力及其在未来可植入环保生物电子学中的诊断、治疗和实时监测方面的应用潜力。
