Miniaturization of synthetic micro/nanomotors (MNMs) brings great application prospects but limits their functionalization ability. Here, we report self-fueled metal organic framework (MOF) micromotors that are endowed with capabilities of self-propulsion and antibacterial therapy by their material’s intrinsic properties. The spontaneous degradation of the MOF micromotors in water would release their own constituting components of ions which act as fuels to propel themselves by ionic diffusionphoresis with a high energy conversion efficiency. Meanwhile, the metal cations released from the MOF micromotors can also serve as antibacterial reagents to kill Escherichia coli (E. coli) with motion enhanced efficacy, which could significantly accelerate the wound closure in a bacterially infected wound model in vivo. Our work provides a general guidance for constructing functional MNMs by taking advantage of the motors’ own materials to achieve self-propulsion and on-demand task assignments, which would promote future development of highly integrated micro/nanorobotic systems at micro/nanoscale.

Four earthquakes above magnitude 5.0 in Yunnan and Tibet, China occurred from 2010 to 2011. By calculating the tidal-force changes induced by celestial bodies in this region, we found that the earthquakes occurred when tidal-forces continuously grew from low to peak levels and approached the maximum amplitude phase, which indicated a tidal-force that had a trigger or inducing effect of active tectonic earthquakes when the ground stress reached a critical point. At the same time analyzing the abnormal changes of outgoing longwave radiation (OLR), along with the tidal cycle, indicated that the regional distribution of the enhancement region of OLR anomalies was closely related to geologic structure, especially active faults. The OLR radiation anomaly evolved: an initial infrared rise, followed by an enhancement reaching peak, attenuation, and then a return to normal. The entire process was similar to changes observed in rock-breaking process under stress loads. Our investigation showed that the tidal-force changes caused by celestial bodies could trigger an earthquake when tectonic stress reached its critical breaking point, and the OLR anomaly was the radiation signature of the change in seismic tectonic stress. Therefore, the method of combining measurements of the tidal-force changes induced by celestial bodies with those of thermal-anomaly changes has some practical value for detecting the precursor state of impending earthquakes.

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