Fig. 6. (a) Transmittance in the ON and OFF states before and after agitation with a vortex mixer for 30 s when IPA only and a mixture of IPA and PEG are used. (b) Microscopic image of the disassembled microrods formed in IPA only after mechanical agitation. (c) Microscopic image of the stable microrods formed in a liquid mixture after mechanical agitation. The scale bars represent 100 μm. (d) Schematic illustration of the PEG coating on the magnetic rods to stabilise them. (e) Transmittance in the ON and OFF states after making the magnetic rods and after 24 h when using Fe₂O₃ and Fe₃O₄. (f) Pictures in the ON and OFF states of a smart window filled with Fe₃O₄ microrods after leaving the sample for a day. (g) Microscopic image of the clustered Fe₃O₄ magnetic rods after a day. The scale bars in (b), (c), and (g) represent 100 μm.