微应变激活导电性的液态金属颗粒墨水的制备及柔性印刷电子应用

Preparation and application of flexible printed electronics of liquid metal particles ink with microstrain-activated conductivity

摘要

用于直接墨水书写 (DIW)的液态金属颗粒 (LMPs) 墨水,需通过机械烧结工艺激活其导电性。然而墨水中过多的高分子会导致导电性激活所需的应变增大,进而引发液态金属泄漏和电导率下降等问题。为减少对机械烧结工艺的依赖,采用调控 LMPs复合聚乙烯吡咯烷酮 (LM-PVP)墨水黏度的方法以实现微应变激活导电性。通过引入乙醇添加剂,将导电性激活所需应变降至约3.6%,同时使激活后的电导率提升至1.2×10⁶ S/m。以乙醇为溶剂的墨水展现出广泛的基底适应性,可在多种基底上实现柔性电子产品的制备,为柔性印刷电子技术的发展开辟了新途径。

Abstract

The liquid metal particles (LMPs) inks used for direct ink writing (DIW) rely on a mechanical sintering process to activate their electrical conductivity. However, excessive polymer content in the ink increases the strain required for conductivity activation, leading to issues such as liquid metal leakage and reduced electrical conductivity. To address these issues, the method of regulating the viscosity of liquid metal particles (LMPs)/polyvinylpyrrolidone (PVP) composite (LM-PVP) inks is adopted to achieve conductivity activation under microstrain. By adding ethanol, the strain required for conductivity activation was reduced to only about 3.6%, while achieving a high conductivity of 1.2×10⁶ S/m after activation. This ink with ethanol as the solvent shows broad substrate adaptability. It can be used to fabricate flexible electronic devices on a wide range of substrates. This new approach offers a practical new way forward for flexible printed electronics technology.

关键词

液态金属颗粒墨水 / 导电性 / 直接墨水书写 / 柔性印刷电子

Key words

liquid metal particles ink / conductivity / direct ink writing / flexible printed electronics

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基金资助

国家自然科学基金(52373201)

国家自然科学基金(52103252)