RESUMEN
Traditional metal-organic frameworks (MOFs) based micro/nanomotors (MOFtors) can achieve three-dimensional (3D) motion mainly depending on noble metal (e.g., Pt), toxic fuels (e.g., hydrogen peroxide), and surfactants, or under external magnetic fields. In this study, light-driven MOFtors are constructed based on PCN-224(H) and regulated their photothermal and photochemical properties responding to the light of different wavelengths through porphyrin metalation. The resulting PCN-224(Fe) MOFtors presented a strong 3D motion at a maximum speed of 1234.9 ± 367.5 µm s-1 under visible light due to the various gradient fields by the photothermal and photochemical effects. Such MOFtors exhibit excellent water sterilization performance. Under optimal conditions, the PCN-224(Cu) MOFtors presented the best antibacterial performance of 99.4%, which improved by 23.4% compared to its static counterpart and 43.7% compared to static PCN-224(H). The underlying mechanism demonstrates that metal doping could increase the production of reactive oxygen species (ROS) and result in a more positive surface charge under light, which are short-distance effective sterilizing ingredients. Furthermore, the motion of MOFtors appears very important to extend the short-distance effective sterilization and thus synergistically improve the antibacterial performance. This work provides a new idea for preparing and developing light-driven MOFtors with multi-responsive properties.
RESUMEN
The design of MOF-based micromotors (MOFtors) is still challenging and with limited approaches, especially for the MOF nanoparticles (NPs). Herein, we report a universal and straightforward strategy to efficiently self-assembly MOF NPs into robust MOFtors for enhanced organic- or heavy-metal-ion-contaminants remediation without mechanical stirring. Based on the transient Pickering emulsion method, Fe3 O4 @NH2 -UiO-66 (Fe-UiO) NPs are rapidly self-assembled into Fe3 O4 @NH2 -UiO-66 colloidosomes (Fe-UiOSomes) on a large scale, and the formation mechanism is systematically studied. The Fe-UiOSomes-Pt micromotors through chemical reduction (Micromotor-C) presented a higher motility of 450±180â µm s-1 in a 5â wt% H2 O2 aqueous solution. Finally, the bubble-propelled Micromotor-C was employed to efficiently remove dyes and heavy metal ions (94 % for MO and 91 % for CrVI ).
RESUMEN
This paper studies the scheduling of autonomous mobile robots (AMRs) at hospitals where the stochastic travel times and service times of AMRs are affected by the surrounding environment. The routes of AMRs are planned to minimize the daily cost of the hospital (including the AMR fixed cost, penalty cost of violating the time window, and transportation cost). To efficiently generate high-quality solutions, some properties are identified and incorporated into an improved tabu search (I-TS) algorithm for problem-solving. Experimental evaluations demonstrate that the I-TS algorithm outperforms existing methods by producing high-quality solutions. Based on the characteristics of healthcare requests and the AMR working environment, scheduling AMRs reasonably can effectively provide medical services, improve the utilization of medical resources, and reduce hospital costs.