Magnetic chains are formed through the interaction between magnetic Ni layers inside the Au@Ni@TiO2 micromotors under external magnetic field. The scheme in Figure A shows the formation of the chain under magnetic field. Correspondingly, the SEM image (Figure ) shows the assembled chain formed by individual Au@Ni@TiO2 micromotors. These assemblies can move directionally in both, H2O and H2O2 solution under magnetic field. As shown in Figure (Video S5, S6), the assembled chain can move directionally at a speed of 7.35 µm s -1 in H2O, and at a speed of 26.96 µm s -1 in 0.1% H2O2 solution with UV light under magnetic field. Despite being slower than single micromotors, the assemblies benefit from the larger area covered by the chain and can achieve considerable shovelling effects, thus holding greater potential for microplastics removal in real environmental filed. To verify the shovelling effect on microplastics and suspended matter removal by assembled chains independent of fuel under magnetic field, different experiments have been carried out in H2O2 solution and H2O.