Solvothermal synthesis of transition metal (iron/copper) and nitrogen co−doped carbon nanomaterials: comparing their peroxidase−like properties

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology Vol. 24; no. 4
• Main Authors: Lee, Bryan, Tian, Siyu, Xiong, Guoping, Yang, Ying, Zhu, Xiaoshan
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2022; Springer Nature B.V
• Subjects: Carbon; Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper; Horseradish peroxidase; Hydrogen peroxide; Inorganic Chemistry; Iron; Lasers; Materials Science; Nanomaterials; Nanoparticles; Nanotechnology; Nitrogen; Optical Devices; Optics; Peroxidase; Photonics; Physical Chemistry; Research Paper; Substrates; Transition metals; Carbon nanomaterial, Synthesis; Nanozyme; Copper-nitrogen; Iron–nitrogen
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-022-05470-y

In this work, iron- and nitrogen-doped carbon nanomaterials (Fe–N-CNMs) and copper- and nitrogen-doped CNMs (Cu–N-CNMs) were synthesized through a facile one-pot solvothermal approach. Their peroxidase-like properties were studied and compared. The Michaelis-constant K m of Fe–N-CNMs with H 2 O 2 or TMB as the primary substrate is 19 µM and 78 µM at optimal conditions, respectively, while K m of Cu–N-CNMs with H 2 O 2 or TMB as the primary substrate is 2.4 mM and 0.44 mM at optimal conditions, respectively. The K m values of both types of materials are lower than or comparable to those of horseradish peroxidase (HRP). Moreover, under the same mass concentration, Fe–N-CNMs is superior to Cu–N-CNMs in achieving higher values of the maximum reaction rate V max (e.g., 5.67 × 10 –8  M/s for Fe–N-CNMs compared to 4.68 × 10 –8  M/s for Cu–N-CNMs with H 2 O 2 as the primary substrate). However, it was also found that under high concentrations of substrates (3,3,5,5′-tetramethylbenzidine (TMB) and hydrogen peroxide (H 2 O 2 )), the reaction rates of Fe–N-CNMs are saturated, but the reaction rates of Cu–N-CNMs are increasing versus the concentrations of substrates and are higher than those of Fe–N-CNMs. Experimental results showed that synergistic efforts of both the catalytic mechanism and the product-microaggregation process could be involved in the Cu–N-CNM-based reaction to enhance the measured reaction rates. Potential applications were discussed on the basis of the reaction characteristics of these two peroxidase-like materials.