Efficient Electrochemical CO2 Reduction to CO by Metal and Nitrogen Co-doped Carbon Catalysts Derived from Pharmaceutical Wastes Adsorbed on Commercial Carbon Nanotubes
Efficient Electrochemical CO2 Reduction to CO by Metal and Nitrogen Co-doped Carbon Catalysts Derived from Pharmaceutical Wastes Adsorbed on Commercial Carbon Nanotubes
复制标题
DOI：
10.1016/j.cej.2022.139712
复制
发表时间：
2022-10
影响因子：
15.1
通讯作者：
Yang Gang;Boyang Li;Siyuan Fang;John E. Pellessier;Lingzhe Fang;Fuping Pan;Zichen Du;Yun Hang Hu;Tao Li;Guofeng Wang;Ying Li
中科院分区：
文献类型：
--
作者：
Yang Gang;Boyang Li;Siyuan Fang;John E. Pellessier;Lingzhe Fang;Fuping Pan;Zichen Du;Yun Hang Hu;Tao Li;Guofeng Wang;Ying Li
过渡金属和氮掺杂的碳催化剂（M单键N单键C）是一种有效的电化学还原CO2为CO的高选择性催化剂。然而，活性金属-氮催化剂的可规模化和成本有效的合成尚待开发。在此，我们报告了一种简单和可持续的方法，利用商业碳纳米管（CNTs）吸附的药物废物，磺胺甲恶唑（SMX），然后适度热解，以制备有效的M单键N单键C催化剂。来自CNT的固有金属杂质对于形成活性金属位点是必不可少的，并且与使用最广泛的氮前体（诸如三聚氰胺和尿素）的方法相比，它需要显著更少的氮前体。CNT-SMX催化剂可提供高CO2 RR性能，在传统H电池中，在−0.76 V（相对于RHE）下具有91.5%的CO法拉第效率和14 mA/cm 2CO局部电流密度。该催化剂在可扩展的流动电池中也是有效的，在300 mA/cm 2下表现出97.5%的CO选择性，加上在100 mA/cm 2下稳定的CO2 RR性能超过24小时。扫描透射电子显微镜（STEM）和X-射线吸收光谱（XAS）分析证实存在的单原子位点主要是在Fe-N键的形式，是活性位点CO2 RR。密度泛函理论（DFT）计算表明，碳纳米管中的Fesingle单键和C单键与Ni纳米颗粒之间存在协同作用，通过降低CO中间体的脱附能，提高了CO的生成速率和选择性.据我们所知，这项工作的结果是最好的碳基催化剂。此外，在这项工作中开发的催化剂在中等温度下合成，无需预氧化或后酸洗，并利用廉价或废料，提供了一种简单，可持续和具有成本效益的方法来合成高活性催化剂。
Transition metal and nitrogen doped carbon catalysts (Msingle bondNsingle bondC) are effective in electrochemical reduction of CO2to CO with a high selectivity. However, scalable and cost-effective synthesis of active metal-nitrogen catalysts is yet to be developed. Herein, we report a simple and sustainable method that utilizes commercial carbon nanotubes (CNTs) to adsorb a pharmaceutical waste, sulfamethoxazole (SMX), followed by moderate pyrolysis to prepare an efficient Msingle bondNsingle bondC catalyst. The intrinsic metal impurities from CNTs are essential to form active metal sites, and it requires significantly less nitrogen precursor than methods using most widely nitrogen precursors such as melamine and urea. The CNT-SMX catalyst delivers high CO2RR performance with 91.5 % CO Faradaic efficiency and 14 mA/cm2CO partial current density at −0.76 V vs RHE in a traditional H-Cell. The catalyst is also efficient in a scalable flow cell, exhibiting 97.5 % CO selectivity at 300 mA/cm2, plus stable CO2RR performance for more than 24 h at 100 mA/cm2. The scanning transmission electron microscopy (STEM) and X-ray absorption spectroscopy (XAS) analyses confirm the existence of single atomic sites primarily in the form of Fe-N bonds that are active sites for CO2RR. Density functional theory (DFT) calculations suggest a synergy between the single atomic Fesingle bondNsingle bondC sites and Ni nanoparticles embedded in the CNTs, which enhances CO production rate and selectivity by lowering the desorption energy of *CO intermediate. To the best of our knowledge, the results in this work are among the top performing carbon-based catalysts. Furthermore, catalysts developed in this work are synthesized at a moderate temperature without pre-oxidation or post-acid-washing and utilize cheap or waste materials, presenting a simple, sustainable, and cost-effective way to synthesize highly active catalysts.