Ionic liquid gating (ILG) that drives the ions incorporate into or extract from the crystal lattice, has emerged as a new pathway to design materials. Although many intriguing emergent phenomena, novel physical properties and functionalities have been obtained, the gating mechanism governing the ion and charge transport remains unexplored. Here, by using the model system of brownmillerite SrCoO_2.5 and the corresponding electric-field controlled tri-state phase transformation among the pristine SrCoO_2.5, hydrogenated HSrCoO_2.5 and oxidized perovskite SrCoO_3−δ through the dual ion switch, the ionic diffusion and electronic transport processes were carefully investigated. Through controlling gating experiment by design, we find out that the collaborative interaction between charge transport and ion diffusion plays an essential role to prompt the hydrogen or oxygen ions incorporate into the crystal lattice of SrCoO_2.5, and therefore leading to formation of new phases. At region closer to the electrode, the electron can shuttle more readily in (out) the material, correspondingly the incorporation of hydrogen (oxygen) ions and phase transformation is largely affiliated. With the compensated charge of electron as well as the reaction front gradually moving away from the electrode, the new phases would be developed successively across the entire thin film. This result unveils the underlying mechanism in the electric-field control of ionic incorporation and extraction, and therefore provides important strategy to achieve high efficient design of material functionalities in complex oxide materials.

驱动离子掺入或从晶格中提取的离子液体门控 (ILG) 已成为设计材料的新途径。尽管已经获得了许多有趣的新兴现象、新的物理性质和功能，但控制离子和电荷传输的门控机制仍未探索。在此，通过使用褐煤 SrCoO _2.5的模型系统和相应的电场控制的原始 SrCoO _2.5、氢化 HSrCoO _2.5和氧化钙钛矿 SrCoO _{3- δ之间的三态相变} 通过双离子开关，仔细研究了离子扩散和电子传输过程。通过设计控制门控实验，我们发现电荷传输和离子扩散的协同作用在促使氢或氧离子进入SrCoO _{2.5的晶格中起着至关重要的作用。}，因此导致新阶段的形成。在靠近电极的区域，电子可以更容易地穿梭进（出）材料，相应地，氢（氧）离子的结合和相变在很大程度上是相关的。随着电子的补偿电荷以及反应前沿逐渐远离电极，新相将在整个薄膜上连续发展。该结果揭示了离子掺入和提取的电场控制的潜在机制，因此为实现复合氧化物材料中材料功能的高效设计提供了重要策略。