Nitrogen doping of graphene with systematically controlled dopant content and distribution of nitrogen species is demonstrated to improve the size distribution of the deposited platinum (Pt) nanoparticles. While the dopant content can be tuned by varying the urea dosage, the doped nitrogen species (namely pyridinic N, pyrrolic N, and graphitic N) can be controlled through the annealing temperature. Chemically reduced Pt nanoparticles were found to be evenly distributed on the nitrogen-doped graphene sheets (NRGO) with particle size centred at 2.7 nm. In comparison, the decoration of Pt on the non-doped graphene (RGO) yielded a composite material with larger Pt (7.8 nm) and poorer size distribution. The loading of Pt nanoparticles is shown to correlate with the concentration of the nitrogen dopant, in particular that of the graphitic N species. Owing to the smaller and better distributed Pt nanoparticles which facilitated more active sites for reaction, the Pt-loaded NRGO photocatalytically generated H2 gas ten times higher than that of Pt-loaded RGO when coupled with photoactive graphitic carbon nitride (g-C3N4).

中文翻译：

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在掺氮石墨烯片上装饰铂：控制铂粒度分布以改进光催化 H 2 生成

具有系统控制的掺杂剂含量和氮物种分布的石墨烯的氮掺杂被证明可以改善沉积的铂 (Pt) 纳米颗粒的尺寸分布。虽然可以通过改变尿素剂量来调整掺杂剂含量，但可以通过退火温度控制掺杂的氮物质（即吡啶 N、吡咯 N 和石墨 N）。发现化学还原的 Pt 纳米粒子均匀分布在掺氮石墨烯片 (NRGO) 上，粒径集中在 2.7 nm。相比之下，Pt 在非掺杂石墨烯 (RGO) 上的装饰产生了具有更大 Pt (7.8 nm) 和更差尺寸分布的复合材料。Pt 纳米颗粒的负载显示与氮掺杂剂的浓度相关，特别是石墨 N 物质的浓度。