Joshi Prerna, Yadav Rohit, De Silva K Kanishka H, Hara Masanori, Shibuya Hayato, Motoyama Yukihiro, Yoshimura Masamichi
Surface Science Laboratory, Toyota Technological Institute, Nagoya 468-8511, Japan.
Catalytic Organic Chemistry Laboratory, Toyota Technological Institute, Nagoya 468-8511, Japan.
ACS Omega. 2022 Aug 10;7(33):29287-29296. doi: 10.1021/acsomega.2c03496. eCollection 2022 Aug 23.
We report the synthesis of nitrogen-doped graphene oxide, with 5.7-7.0 wt % nitrogen doping, from different sizes of precursor graphite and study its effect on the oxygen evolution reaction (OER) activity of IrO in an acidic medium. The nitrogen-doped supports are expected to have pyridinic, pyrrolic, and graphitic functionalities at different ratios responsible for their improved performance. The N-doped supports and catalysts are synthesized pyrolysis and the hydrothermal method using natural and synthetic graphite of three different flake sizes and evaluated for their structural and electrochemical characteristics. The average size of IrO nanoparticles deposited on the N-doped supports is independent of the flake size and doping amount of nitrogen. The catalysts show optimum current densities but improved stability with increasing flake sizes of 7, 20, and 125 μm. Our results demonstrate that the selection of the flake size of the doped support is necessary to achieve durable catalysts for the OER in an acidic medium.
我们报道了从不同尺寸的前驱体石墨合成氮掺杂量为5.7 - 7.0 wt%的氮掺杂氧化石墨烯，并研究了其在酸性介质中对IrO析氧反应（OER）活性的影响。预计氮掺杂载体具有不同比例的吡啶型、吡咯型和石墨型官能团，这是其性能提高的原因。使用三种不同片状尺寸的天然和合成石墨，通过热解和水热法合成了氮掺杂载体和催化剂，并对其结构和电化学特性进行了评估。沉积在氮掺杂载体上的IrO纳米颗粒的平均尺寸与片状尺寸和氮掺杂量无关。随着片状尺寸增加到7、20和125μm，催化剂显示出最佳电流密度，但稳定性有所提高。我们的结果表明，选择掺杂载体的片状尺寸对于在酸性介质中实现用于OER的耐用催化剂是必要的。
