Abstract Commercially available Cu foils are leading candidates as substrates employed for the generation of large-area graphene using chemical vapour deposition (CVD) techniques. However, the growth of high-quality graphene on Cu foils is often hindered by contamination particles, which will also be detrimental for many potential applications of graphene. Here we investigate the influence of typical substrate impurities on the formation of CVD graphene using as-received Cu foils of various purities from different suppliers and the same cleaned by popular methods. Analytical characterisation of the Cu foils revealed that contamination particles consist of calcium, aluminium, and silicon oxides. We show that contamination particles are present on foils with purities ranging between 99.8% and 99.9999% and that these particles influence the nucleation density, growth rate, and growth features of graphene domains. Based on our findings we propose new industrially applicable targeted cleaning procedures of immersion in purposely-selected HCl and KOH solutions to chemically dissolve the aforementioned impurities, bringing about improved growth of graphene.

中文翻译：

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有针对性地去除铜箔表面杂质以改进 CVD 石墨烯的合成

摘要 市售的铜箔是使用化学气相沉积 (CVD) 技术生成大面积石墨烯的主要候选材料。然而，高质量石墨烯在铜箔上的生长往往受到污染颗粒的阻碍，这也将不利于石墨烯的许多潜在应用。在这里，我们使用来自不同供应商的各种纯度的原样铜箔并通过常用方法清洁相同的铜箔，研究典型基板杂质对 CVD 石墨烯形成的影响。铜箔的分析表征表明，污染颗粒由钙、铝和氧化硅组成。我们表明，污染颗粒存在于纯度在 99.8% 到 99% 之间的箔上。9999% 并且这些粒子影响石墨烯域的成核密度、生长速率和生长特征。基于我们的研究结果，我们提出了新的工业适用的靶向清洁程序，即浸入特意选择的 HCl 和 KOH 溶液中，以化学方式溶解上述杂质，从而改善石墨烯的生长。