Open AccessHigh surface area nitrogen-functionalized Ni nanozymes for efficient peroxidase-like catalytic activity
Author(s) -
Anuja Tripathi,
Kenneth D. M. Harris,
Anastasia L. Elias
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0257777
Subject(s) - catalysis , surface modification , wetting , chemical engineering , x ray photoelectron spectroscopy , nitrogen , substrate (aquarium) , ammonia , materials science , inductively coupled plasma , plasma , chemistry , nanotechnology , organic chemistry , oceanography , physics , quantum mechanics , engineering , geology
Nitrogen-functionalization is an effective means of improving the catalytic performances of nanozymes. In the present work, plasma-assisted nitrogen modification of nanocolumnar Ni GLAD films was performed using an ammonia plasma, resulting in an improvement in the peroxidase-like catalytic performance of the porous, nanostructured Ni films. The plasma-treated nanozymes were characterized by TEM, SEM, XRD, and XPS, revealing a nitrogen-rich surface composition. Increased surface wettability was observed after ammonia plasma treatment, and the resulting nitrogen-functionalized Ni GLAD films presented dramatically enhanced peroxidase-like catalytic activity. The optimal time for plasma treatment was determined to be 120 s; when used to catalyze the oxidation of the colorimetric substrate TMB in the presence of H 2 O 2 , Ni films subjected to 120 s of plasma treatment yielded a much higher maximum reaction velocity (3.7⊆10 −8 M/s vs. 2.3⊆10 −8 M/s) and lower Michaelis-Menten coefficient (0.17 mM vs. 0.23 mM) than pristine Ni films with the same morphology. Additionally, we demonstrate the application of the nanozyme in a gravity-driven, continuous catalytic reaction device. Such a controllable plasma treatment strategy may open a new door toward surface-functionalized nanozymes with improved catalytic performance and potential applications in flow-driven point-of-care devices.