Guo Zichang, Jin Dongdong, Li Haohui, Zhu Xinyu, Zheng Tianqi, Xu Zirong, Chen Yi, Liu Xiaojia, Song Yinuo, Wang Dai, Yan Xiaohui, Ma Xing
Sauvage Laboratory for Smart Materials, School of Integrated Circuits, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
State Key Laboratory of Vaccines for Infectious Diseases, Center for Molecular Imaging and Translational Medicine, Xiang An Biomedicine Laboratory, School of Public Health, Xiamen University, Xiamen 361005, China.
ACS Nano. 2025 Jun 3;19(21):20037-20050. doi: 10.1021/acsnano.5c03785. Epub 2025 May 19.
Photocatalytic micro/nanomotors (MNMs) driven by electrophoresis have attracted considerable attention by virtue of their active mobility and versatile functionality. However, the rapid recombination of photogenerated electron-hole pairs on light illumination severely compromises the involvement of charge species in the catalytic redox reactions of fuels, thus hindering both the propulsion and the application performance of photocatalytic MNMs. Herein, we report a facile strategy to amplify charge separation by incorporating liquid metal (LM) into the construction of photocatalytic MNMs, thereby strengthening the electrophoretic propulsion of MNMs and promoting the generation of reactive oxygen species (ROS) for antibacterial application. The MNMs are constructed with a gallium (Ga) LM core, coated with abundant graphite-phase carbon nitride (g-CN) nanosheets and half covered by a thin platinum layer. These MNMs exhibit self-propulsion in hydrogen peroxide (HO) solution, with their motion dynamics further enhanced by light irradiation. Theoretical calculations and simulations reveal that the composition between Ga and g-CN forms an ohmic junction in the electronic energy band structure, which effectively improves the charge separation efficiency of electron-hole pairs. These results align well with the experimental electrochemical tests and consequently intensify the catalytic redox reactions of HO, as well as accelerate the charge migration across MNMs, contributing to the enhancement of their propulsion performance. Simultaneously, the amplified separation of electrons facilitates increased ROS generation, empowering the MNMs with motion-enhanced antibacterial activity against . Finally, an in vivo wound healing experiment is conducted, verifying the superior antibacterial therapeutic performance of photocatalytic MNMs. This work not only provides insights into the role of charge species in phoretic motion of MNMs but also gives inspiration for developing photocatalytic MNMs with advanced biomedical applications.
基于电泳驱动的光催化微纳马达（MNMs）凭借其活跃的移动性和多功能性受到了广泛关注。然而，光照下光生电子 - 空穴对的快速复合严重阻碍了电荷物种参与燃料的催化氧化还原反应，从而影响了光催化MNMs的推进性能和应用性能。在此，我们报道了一种简便的策略，通过将液态金属（LM）引入光催化MNMs的结构中来增强电荷分离，从而强化MNMs的电泳推进，并促进用于抗菌应用的活性氧物种（ROS）的生成。MNMs由镓（Ga）液态金属核心构建而成，表面包覆有大量石墨相氮化碳（g-CN）纳米片，且一半被薄铂层覆盖。这些MNMs在过氧化氢（HO）溶液中表现出自推进能力，光照进一步增强了它们的运动动力学。理论计算和模拟表明，Ga与g-CN之间的组成在电子能带结构中形成了欧姆结，有效提高了电子 - 空穴对的电荷分离效率。这些结果与实验电化学测试结果高度吻合，进而强化了HO的催化氧化还原反应，并加速了MNMs上的电荷迁移，有助于提高其推进性能。同时，电子的增强分离促进了ROS的更多生成，使MNMs对具有运动增强的抗菌活性。最后，进行了体内伤口愈合实验，验证了光催化MNMs卓越的抗菌治疗性能。这项工作不仅深入了解了电荷物种在MNMs电泳运动中的作用，还为开发具有先进生物医学应用的光催化MNMs提供了灵感。
