...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Catalysis science & technology >N-Coordinated Ir single atoms anchored on carbon octahedrons for catalytic oxidation of formaldehyde under ambient conditions
【24h】

N-Coordinated Ir single atoms anchored on carbon octahedrons for catalytic oxidation of formaldehyde under ambient conditions

机译：在环境条件下，在碳八面体上锚定甲醛催化氧化的N配位IR单原子用于催化氧化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Molecular oxygen activation over single atoms catalysts (SACs) has been a thorny issue in catalytic oxidation of toxic formaldehyde (HCHO) under ambient conditions. Metal oxide supported SACs are far from satisfactory due to the insufficient oxygen activation and high temperature (>20 °C) for complete oxidation of HCHO. Herein, N-doped carbon was selected as a non-oxide support to stabilize iridium single atoms (Ir1–N–C), which could deliver high HCHO removal and conversion efficiency (>95%) with high/low concentrations at 20 °C. The specific rate can reach 401.8 mmol gIr−1 h−1, superior to that of Ir-based catalysts reported to date. The local structure of Ir–N4 sites was confirmed by spherical aberration correction electron microscopy and X-ray absorption fine structure. Based on the theory calculations and electron spin resonance results, the strong electronegativity of N atoms in Ir–N4 active sites enhanced the polarization of Ir atoms, thus forming strong electronic coupling between the Ir 5d orbitals and O2 2p orbitals, promoting the dissociation of O2. In situ diffuse reflectance infrared Fourier transform spectroscopy revealed the main reaction pathways. Dioxymethylene (DOM) and formate species were detected as the intermediates. This work enlightens the great potential of Ir SACs supported on non-oxides in air purification including HCHO.
机译：在环境条件下，单个原子催化剂（SAC）对单个原子催化剂（SAC）的分子氧活化一直是毒性甲醛（HCHO）的棘手问题。由于氧气激活不足和高温（> 20°C），无法完全氧化HCHO，因此氧化金属支撑的囊远非令人满意。在此，选择了N掺杂的碳作为非氧化物支持，以稳定虹膜单原子（IR1 – N – C），可在20°C下具有高/低浓度的高HCHO去除和转化效率（> 95％） 。特定速率可以达到401.8 mmol GIR-1 H-1，优于迄今为止报告的基于IR的催化剂。通过球形像差校正电子显微镜和X射线吸收精细结构证实了IR – N4位点的局部结构。基于理论计算和电子自旋共振结果，IR – N4活性位点N原子的强电负性增强了IR原子的极化，从而形成了IR 5D轨道和O2 2P轨道之间的强电子耦合，从而促进了O2的解离。原位弥散反射率红外傅立叶变换光谱揭示了主要反应途径。检测到二氧甲基（DOM）和甲酸物种为中间体。这项工作启发了包括HCHO在内的空气纯化中支持非氧化物的IR囊的巨大潜力。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号