Boon Niels, Olvera de la Cruz Monica
Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Soft Matter. 2015 Jun 28;11(24):4793-8. doi: 10.1039/c5sm00573f. Epub 2015 May 20.
Soft materials can be used as the building blocks for electronic devices with extraordinary properties. We introduce a theoretical model for a field-effect transistor in which ions are the gated species instead of electrons. Our model incorporates readily-available soft materials, such as conductive porous membranes and polymer-electrolytes to represent a device that regulates ion currents and can be integrated as a component in larger circuits. By means of Nernst-Planck numerical simulations as well as an analytical description of the steady-state current we find that the responses of the system to various input voltages can be categorized into ohmic, sub-threshold, and active modes. This is fully analogous to what is known for the electronic field-effect transistor (FET). Pivotal FET properties such as the threshold voltage and the transconductance crucially depend on the half-cell redox potentials of the source and drain electrodes as well as on the polyelectrolyte charge density and the gate material work function. We confirm the analogy with the electronic FETs through numerical simulations of elementary amplifier circuits in which we successfully substitute the electronic transistor by an ionic transistor.
软材料可作为具有非凡特性的电子设备的构建材料。我们引入了一种场效应晶体管的理论模型，其中离子作为被门控的物种而非电子。我们的模型纳入了现成的软材料，如导电多孔膜和聚合物电解质，以代表一种调节离子电流且可作为组件集成到更大电路中的器件。通过能斯特 - 普朗克数值模拟以及稳态电流的解析描述，我们发现系统对各种输入电压的响应可分为欧姆、亚阈值和有源模式。这与电子场效应晶体管（FET）的情况完全类似。诸如阈值电压和跨导等关键的FET特性，关键取决于源极和漏极电极的半电池氧化还原电位，以及聚电解质电荷密度和栅极材料功函数。我们通过对基本放大器电路的数值模拟证实了与电子FET的类比，在模拟中我们成功地用离子晶体管替代了电子晶体管。
