N-doped semi-graphitic C loaded with metallic Co: synthesis parameters and catalytic selective reduction of -nitrophenol

• Published in: New journal of chemistry Vol. 47; no. 8; pp. 3834 - 3846
• Main Authors: Zhang, Qinjun, Lu, Xinhuan, Yue, Fanfan, Guo, Haotian, Shi, Congxing, Tao, Yiyuan, Duan, Jingui, Zhou, Dan, Xia, Qinghua
• Format: Journal Article
• Published: 20.02.2023
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d2nj05922c

p -Nitrophenol (PNP) is an important pesticide intermediate, and is also a water pollutant that is extremely harmful to personal health. It can be converted to p -aminophenol (PAP) through selective catalytic hydrogenation reduction. This work reports that the Co/CN- x ( x is the pyrolysis temperature) catalysts derived from the precursor Co-ZIF-9 could catalyze highly selective hydrogenation of PNP with H 2 to PAP. The obtained N-doped semi-graphitic C loaded with a metallic Co (Co/CN) catalyst had an extraordinary morphology and exhibited excellent catalytic hydrogenation activity. The size effect of Co NPs dispersed on nitrogen-carbon materials played a critical role in promoting the reaction efficiency. It was found that the conversion of PNP reached 100% and the selectivity of PAP was 98.5% over Co/CN-350 under mild reaction conditions. In addition, Co/CN- x catalysts also displayed excellent substrate tolerance and good recyclability with a catalytic performance remaining between 97.4% and 100% with 14 recycles. This work not only provides a new idea for the application of environment-friendly Co-based catalysts, but also opens up a suitable catalytic route for selective hydrogenation of nitrophenols. The N-doped semi-graphitic C loaded with metallic Co (Co/CN) could catalyze highly selective hydrogenation of p -nitrophenol (100% conversion) to p -aminophenol (98.5% selectivity). The magnetically separable catalyst was reusable for 14 cycles.