Synergistic effects between polyvinylpyrrolidone and oxygen vacancies on improving the oxidase-mimetic activity of flower-like CeO2 nanozymes. Issue 37 (21st July 2020)

• Record Type: Journal Article
• Authors: Zhu, Mingyun; Wen, Yifeng; Song, Shugui; Zheng, Anqi; Li, Jingcang; Sun, Weiwei; Dai, Yunqian; Yin, Kuibo; Sun, Litao
• Is Part Of: Nanoscale. Volume 12:Issue 37(2020)
• Page Start: 19104
• Page End: 19111
• Publication Date: 2020-07-21
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d0nr04177g
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : The synergy between polyvinylpyrrolidone and enriched oxygen vacancies can promote the adsorption of reactants (TMB and O2 ) and desorption of reaction products, which results in the enhanced oxidase-mimetic activity of CeO2 nanoflowers. Abstract : Both oxygen vacancies and surface chemistry can affect the enzyme-like catalytic activities of CeO2 -based nanozymes. However, the mechanism of the enzyme-mimetic process is not yet clearly elucidated, which is of great importance to guide the synthesis of high-performance nanozymes with desirable properties. Herein, we report a facile one-pot solvothermal method for the preparation of polyvinylpyrrolidone (PVP)-capped CeO2 nanoflowers with adjustable oxygen vacancies by changing appropriate solvothermal reaction parameters. Oxygen vacancies effectively increase under a higher precursor concentration, extended solvothermal time, and proper reaction temperature. The maximum content of surface Ce(iii ) cations is up to 50% for 31.1 nm CeO2 nanoflowers, which exhibit 0.07 mM apparent Michaelis constant towards 3, 3′, 5, 5′-tetramethylbenanozymeidine and show a higher binding affinity than the other CeO2 -based catalysts. Theoretical results indicate that the synergy between PVP and oxygen vacancies can significantly promote the adsorption of O2 and TMB on CeO2, which directly enhances the oxidase-mimetic activity of flower-like CeO2 nanozymes. This work can shed light on a new perspective on the enzyme-like performance promotion of CeO2 -based catalysts and surface engineering of nanozymes.