Lawrence Livermore National Laboratory , Livermore , California 94550 , United States.
Department of Chemistry , University of California Riverside , Riverside , California 92521 , United States.
ACS Appl Mater Interfaces. 2018 Oct 31;10(43):36860-36865. doi: 10.1021/acsami.8b10349. Epub 2018 Oct 22.
Understanding and controlling the electrical response at a complex electrode-electrolyte interface is key to the development of next-generation supercapacitors and other electrochemical devices. In this work, we apply a theoretical framework based on the effective screening medium and reference interaction site model to explore the role of electrical double-layer (EDL) formation and its interplay with quantum capacitance in graphene-based supercapacitors. In addition to pristine graphene, we investigate a novel C-modified graphene supercapacitor material, which promises higher charge-storage capacity. Beyond the expected enhancement in the quantum capacitance, we find that the introduction of C molecules significantly alters the EDL response. These changes in EDL are traced to the interplay between surface morphology and charge localization character and ultimately dominate the overall capacitive improvement in the hybrid system. Our study highlights a complex interplay among surface morphology, electronic structure, and interfacial capacitance, suggesting general improvement strategies for optimizing carbon-based supercapacitor materials.
理解和控制复杂的电极-电解质界面的电响应是开发下一代超级电容器和其他电化学器件的关键。在这项工作中，我们应用了基于有效屏蔽介质和参考相互作用位点模型的理论框架，来探索双电层（EDL）形成及其与基于石墨烯的超级电容器中的量子电容相互作用的作用。除了原始石墨烯外，我们还研究了一种新型的 C 修饰石墨烯超级电容器材料，该材料有望提供更高的电荷存储容量。除了预期的量子电容增强之外，我们还发现 C 分子的引入显著改变了 EDL 的响应。这些 EDL 的变化可归因于表面形态和电荷定位特性之间的相互作用，最终主导了混合系统中整体电容的改善。我们的研究强调了表面形态、电子结构和界面电容之间的复杂相互作用，为优化基于碳的超级电容器材料提供了一般的改进策略。
