کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5435044 | 1509147 | 2017 | 9 صفحه PDF | دانلود رایگان |
- Coral-like CeO2/NiO nanocomposites with different Ce content were synthesized.
- CeO2 was highly dispersed in the NiO matrixes with high surface area.
- CeO2/NiO nanocomposites exhibited efficient peroxidase-like activity.
- A colorimetric H2O2 sensor was constructed based on the efficient peroxidase-like activity.
Development of nanomaterials-based enzymatic mimics has gained considerable attention in recent years, because of their low cost, high stability and efficiently catalytic ability. Here, CeO2 was successfully incorporated into the coral-like NiO nanostructures assembled by nanoflakes with high surface area, forming the coral-like CeO2/NiO nanocomposites. The morphology and composition of CeO2/NiO nanocomposites were characterized by XRD, SEM, element mapping and XPS. The results of characterization showed that cerium was highly dispersed in the coral-like NiO nanostructures. The peroxidase-like activity of CeO2/NiO nanocomposites was investigated, and they exhibited enhanced peroxidase-like activity in comparison to that of pure NiO or CeO2. The catalytic activity was dependent on the cerium content, and the optimal content was 2.5%. The enhanced catalytic activity of CeO2/NiO nanocomposites arised from their high ability of electron transfer because of cerium incorporation. The catalytic performance of CeO2/NiO nanocomposites was evaluated by steady-state kinetic, which showed that the CeO2/NiO nanocomposites exhibited higher affinity for the substrates and similar catalytic efficiency compared with natural peroxidase. Based on the efficient peroxidase-like activity, CeO2/NiO was used for H2O2 determination. The constructed colorimetric H2O2 sensor had fast response for only 5 min, a wide linear range from 0.05 to 40 mM and a low detection limit with 0.88 μM. The CeO2/NiO nanocomposites were expected to have potential applications in clinical diagnosis and biotechnology as enzymatic mimics.
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Journal: Materials Science and Engineering: C - Volume 74, 1 May 2017, Pages 434-442