Zhang Tao, Zuo Songlin
International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
Molecules. 2024 Jul 30;29(15):3611. doi: 10.3390/molecules29153611.
Besides outstanding catalytic performance, the stability of nitrogen-doped carbon materials during storage is equally crucial for practical applications. Therefore, we conducted the first investigation into the stability of highly nitrogen-doped activated carbon (AC-NC-T) obtained by modifying activated carbon with CO/NH in different storage media (air, vacuum and N). The results of the catalysis of the oxygen reduction reaction and the activation of peroxymonosulfate for degrading bisphenol A by AC-NC-T show that the catalytic activity of AC-NC-T stored in air decays most prominently, while the performance attenuated only marginally when stored in vacuum and N. The results from N adsorption isotherms, Raman spectroscopy, elemental and X-ray photoelectron spectroscopy indicate that the decline in catalytic activity is due to the presence of oxygen in the environment, causing a decrease in absolute contents of pyridinic N (N-6) and graphitic nitrogen (N-Q). After being stored in an air atmosphere for 28 days, the absolute contents of N-6 and N-Q in AC-NC-950 decreased by 19.3% and 12.1%, respectively. However, when stored in a vacuum or N, the reduction in both was less than 7%. This study demonstrates that reducing oxygen concentration during storage is crucial for preserving high catalytic activity of nitrogen-containing carbon materials.
除了出色的催化性能外，氮掺杂碳材料在储存期间的稳定性对于实际应用同样至关重要。因此，我们首次对通过在不同储存介质（空气、真空和氮气）中用CO/NH改性活性炭获得的高氮掺杂活性炭（AC-NC-T）的稳定性进行了研究。AC-NC-T对氧还原反应的催化以及对过一硫酸盐活化降解双酚A的结果表明，储存在空气中的AC-NC-T的催化活性衰减最为显著，而在真空和氮气中储存时性能仅略有衰减。氮气吸附等温线、拉曼光谱、元素分析和X射线光电子能谱的结果表明，催化活性的下降是由于环境中存在氧气，导致吡啶氮（N-6）和石墨氮（N-Q）的绝对含量降低。在空气气氛中储存28天后，AC-NC-950中N-6和N-Q的绝对含量分别下降了19.3%和12.1%。然而，当在真空或氮气中储存时，两者的下降均小于7%。这项研究表明，储存期间降低氧气浓度对于保持含氮碳材料的高催化活性至关重要。
