Fig. 6. M − H curves of the Fe₃O₄ and Fe₃O₄–Ag Janus 10 h particles. The insets in the top left are photographs of the samples in solution, Fe₃O₄ (left) and Fe₃O₄–Ag Janus (right). The insets in the bottom right are photographs of the Fe₃O₄–Ag Janus 10 h taken before and after magnetic attraction by an applied magnet.