We report on the development of a very simple and robust reference electrode suitable for use in room temperature ionic liquids, that can be employed with planar devices. The reference electrode is based on LiFePO₄ (LFP), a common cathode material in Li-ion batteries, which is air and water stable. The reference electrode can be drop-cast onto a planar electrode device in a single step. We demonstrate that very low Li⁺-ion concentrations (millimolar or below) are sufficient to obtain a stable and reproducible LFP potential, thus making physical separation between the reference and working electrode unnecessary. Most importantly, the LFP potential is also entirely stable in the presence of oxygen and shows only a very small drift (<10 mV) in the presence of hydrogen gas, while the potential of a platinum pseudo-reference electrode is shifted >800 mV. This is the first time that such a stable reference electrode system for ionic liquids has been implemented in miniaturized, planar electrode devices.

我们报告了一种非常简单且坚固的参比电极的开发，该参比电极适用于室温离子液体，可与平面设备一起使用。参比电极基于LiFePO ₄（LFP），这是锂离子电池中常见的阴极材料，具有空气和水稳定性。可以在单个步骤中将参比电极滴铸到平面电极装置上。我们证明极低的Li ⁺离子浓度（毫摩尔或以下）足以获得稳定且可重现的LFP电位，因此无需在参比电极和工作电极之间进行物理分离。最重要的是，在有氧存在的情况下，LFP电位也完全稳定，在有氢气存在的情况下，LFP电位仅表现出很小的漂移（<10 mV），而铂假参比电极的电位偏移> 800 mV。这是首次在小型化的平面电极设备中实现了这种稳定的离子液体参比电极系统。