The graphene-water interface is acidic

التفاصيل البيبلوغرافية
العنوان: The graphene-water interface is acidic
المؤلفون: Advincula, Xavier R., Fong, Kara D., Michaelides, Angelos, Schran, Christoph
سنة النشر: 2024
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Physics - Chemical Physics, Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: Water's ability to autoionize into hydroxide and hydronium ions profoundly influences surface properties, rendering interfaces either basic or acidic. While it is well-established that the water-air interface is acidic, a critical knowledge gap exists in technologically relevant surfaces like the graphene-water interface. Here we use machine learning-based simulations with first-principles accuracy to unravel the behavior of the hydroxide and hydronium ions at the graphene-water interface. Our findings reveal that the graphene-water interface is acidic, with the hydronium ion predominantly residing in the first contact layer of water. In contrast, the hydroxide ion exhibits a bimodal distribution, found both near the surface and towards the interior layers. Analysis of the underlying electronic structure reveals strong polarization effects, resulting in counterintuitive charge rearrangement. Proton propensity to the graphene-water interface challenges the interpretation of surface experiments and is expected to have far-reaching consequences for ion conductivity, interfacial reactivity, and proton-mediated processes.
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2408.04487
رقم الأكسشن: edsarx.2408.04487
قاعدة البيانات: arXiv