Oxygen reduction reaction (ORR) plays a vital role in various fields, such as combustion, corrosion and fuel cell applications. Herein, we report the production of phosphorus-doped reduced graphene oxide (P-RGO) using triphenyl phosphine as a phosphorus source and graphene oxide in supercritical fluid method. The ratio of phosphorus source and graphene oxide has been varied to obtain optimum P-doping. P-RGO materials are characterized through X-ray diffractometer, Raman, field emission scanning electron microscopy and X-ray photoelectron spectroscopy techniques. The electrocatalytic activity of P-RGO materials are studied using linear sweep voltammetry and their ORR performance are evaluated using linear sweep voltammetry-rotating ring disk electrode studies in 0.1 M KOH electrolyte. Among the three different P-RGO materials, RGO with phosphorus doping (2:1) delivered the best ORR performance (0.75 A mg −1 ) compared to commercial HiSPEC Pt/C (0.12 A mg −1 ) catalyst. The enhanced ORR activity could be ascribed to the existence of surface-active phosphorous sites over the RGO sheet surface.

中文翻译：

---

使用超临界流体处理磷掺杂石墨烯对氧还原反应的高效电催化活性

氧还原反应 (ORR) 在燃烧、腐蚀和燃料电池应用等各个领域都发挥着至关重要的作用。在此，我们报告了使用三苯基膦作为磷源和氧化石墨烯在超临界流体方法中生产掺磷还原氧化石墨烯 (P-RGO)。改变磷源和氧化石墨烯的比例以获得最佳的 P 掺杂。P-RGO 材料通过 X 射线衍射仪、拉曼、场发射扫描电子显微镜和 X 射线光电子能谱技术进行表征。使用线性扫描伏安法研究 P-RGO 材料的电催化活性，并在 0.1 M KOH 电解质中使用线性扫描伏安法-旋转环盘电极研究评估其 ORR 性能。在三种不同的 P-RGO 材料中，与商业 HiSPEC Pt/C (0.12 A mg -1 ) 催化剂相比，具有磷掺杂 (2:1) 的 RGO 提供了最佳的 ORR 性能 (0.75 A mg -1 )。增强的 ORR 活性可归因于 RGO 片表面上存在表面活性磷位点。