Improving reaction selectivity is the next target for nanozymes to mimic natural enzymes. Currently, the majority of strategies in this field are exclusively applicable to metal-organic-based or organic-based nanozymes, while limited in regulating metal oxide-based semiconductor nanozymes. Herein, taking semiconductor Co₃O₄ as an example, a heterojunction strategy to precisely regulate nanozyme selectivity by simultaneously regulating three vital factors including band structure, metal valence state, and oxygen vacancy content is proposed. After introducing MnO₂ to form Z-scheme heterojunctions with Co₃O₄ nanoparticles, the catalase (CAT)-like and peroxidase (POD)-like activities of Co₃O₄ can be precisely regulated since the introduction of MnO₂ affects the position of the conduction bands, preserves Co in a higher oxidation state (Co³⁺), and increases oxygen vacancy content, enabling Co₃O₄-MnO₂ exhibit improved CAT-like activity and reduced POD-like activity. This study proposes a strategy for improving reaction selectivity of Co₃O₄, which contributes to the development of metal oxide-based semiconductor nanozymes.

中文翻译：

---

异质结介导的能带结构和价态的共同调节实现半导体纳米酶的选择性调控

提高反应选择性是纳米酶模仿天然酶的下一个目标。目前，该领域的大多数策略仅适用于金属有机基或有机基纳米酶，而仅限于调控金属氧化物基半导体纳米酶。本文以半导体Co ₃ O ₄为例，提出了一种通过同时调控能带结构、金属价态和氧空位含量三个重要因素来精确调控纳米酶选择性的异质结策略。引入MnO _{2与Co 3} O ₄纳米粒子形成Z型异质结后，由于MnO ₂的引入影响了位置，因此可以精确调控Co ₃ O ₄的过氧化氢酶（CAT）和过氧化物酶（POD）活性。导带的变化，将Co保持在较高的氧化态(Co ³⁺ )，并增加氧空位含量，使得Co ₃ O ₄ -MnO ₂表现出改善的CAT样活性和降低的POD样活性。本研究提出了提高Co ₃ O ₄反应选择性的策略，有助于金属氧化物基半导体纳米酶的发展。