Platinum nanoparticles encapsulated in nitrogen-doped graphene quantum dots: Enhanced electrocatalytic reduction of oxygen by nitrogen dopants
Platinum nanoparticles encapsulated in nitrogen-doped graphene quantum dots: Enhanced electrocatalytic reduction of oxygen by nitrogen dopants
复制标题
DOI：
10.1016/j.ijhydene.2017.10.078
复制
发表时间：
2017-12
影响因子：
7.2
通讯作者：
Limei Chen;Yi Peng;Jia-En Lu;Nan Wang;Peiguang Hu;Bingzhang Lu;Shaowei Chen
中科院分区：
文献类型：
--
作者：
Limei Chen;Yi Peng;Jia-En Lu;Nan Wang;Peiguang Hu;Bingzhang Lu;Shaowei Chen
通过柠檬酸和尿素水热处理制备的氮掺杂石墨烯量子点（NGQD）被用作通过一氧化碳还原水中 Pt（IV）合成的铂纳米颗粒的有效载体。 TEM 测量结果表明，与 AFM 测量结果相比，铂纳米粒子的直径为 2.03 ± 0.43 nm，并包裹着一层 NGQD。 XPS 测量证实了金属铂的形成以及氮掺杂剂在石墨分子骨架中的结合，Pt 4f 结合能的变化表明，与未掺杂 GQD（Pt-GQD）上负载的铂纳米颗粒相比，负电性更大的氮掺杂剂促进了从 Pt 到 NGQD 的电荷转移。因此，与 Pt-GQD 相比，Pt-NGQD 纳米复合材料在碱性介质中对氧还原反应的催化活性显着增强，其比活性是商业 Pt/C 的三倍以上。与 NGQDs 支持的金纳米粒子的进一步比较表明，铂纳米粒子而不是 NGQDs 在确定 ORR 活性方面发挥了主导作用。
Nitrogen-doped graphene quantum dots (NGQDs) prepared by hydrothermal treatment of citric acid and urea were used as an effective support for platinum nanoparticles synthesized by carbon monoxide reduction of Pt(IV) in water. TEM measurements showed that the platinum nanoparticles were 2.03 ± 0.43 nm in diameter, and wrapped with one layer of NGQDs, as compared to results from AFM measurements. XPS measurements confirmed the formation of metallic platinum and the incorporation of nitrogen dopants within the graphitic molecular skeleton, and the shifts of Pt 4f binding energy suggested that charge transfer from Pt to NGQDs was facilitated by the more electronegative nitrogen dopants, as compared to platinum nanoparticle supported on undoped GQDs (Pt-GQDs). Because of this, the Pt-NGQDs nanocomposites showed markedly enhanced catalytic activity towards oxygen reduction reactions in alkaline media, as compared to Pt-GQDs, with a specific activity more than three times that of commercial Pt/C. Further comparison with NGQDs-supported gold nanoparticles showed that the platinum nanoparticles, rather than the NGQDs, played a dominant role in determining the ORR activity.