Co 3 O 4 /CoFe 2 O 4 Hollow Nanocube Multifunctional Nanozyme with Oxygen Vacancies for Deep-Learning-Assisted Smartphone Biosensing and Organic Pollutant Degradation

作者：Shaojuan Jiang, Gehong Su, Jianbing Wu, Chang Song, Zhiwei Lu, Wu Chun, Yanying Wang, Pingrong Wang, Mingxia He, Ying Zhao, Yuanyuan Jiang, Xiao‐Qing Zhao, Hanbing Rao, Mengmeng Sun · 发表于：ACS Applied Materials & Interfaces · 年份：2023 · DOI：10.1021/acsami.2c22136 · 被引用次数：101 · 研究领域：Advanced Nanomaterials in Catalysis、Advanced biosensing and bioanalysis techniques、Electrochemical sensors and biosensors

Although the application of nanozymes has been widely studied, it is still a huge challenge to develop highly active and multifunctional nanozyme catalysts with a wider application prospect. Co 3 O 4 /CoFe 2 O 4 hollow nanocubes (HNCs) with oxygen vacancies were proposed in this study, which had a porous oxide heterostructure with CoFe 2 O 4 as the core and Co 3 O 4 as the shell. The Co 3 O 4 /CoFe 2 O 4 HNCs had three enzyme activities: peroxidase-like, oxidase-like, and catalase-like. Combining XPS depth profiling with density functional theory (DFT), the catalytic mechanism of peroxidase-like activity was explored in depth, which was mainly originated from ·OH produced by the synergistic effect between the outer oxygen and inner oxygen and electron transfer between Co and Fe. A colorimetry/smartphone dual sensing platform was designed based on the peroxidase-like activity. Especially, a multifunctional intelligent sensing platform based on deep learning-YOLO v3 algorithm-assisted smartphone was constructed to realize real-time and rapid in situ detection of l -cysteine, norfloxacin, and zearalenone. Surprisingly, the detection limit of norfloxacin was low at 0.015 μM, which was better than that of the newly published detection method in the field of nanozymes. Meanwhile, the detection mechanism of l -cysteine and norfloxacin was successfully investigated by in situ FTIR. In fact, it also showed outstanding applications in detecting l -cysteine in the food environment and n...