Figure 7

M-H curves of (a) the comparative Bi2S3 sample; (b) the multi-level hollow Bi2S3 spheres and (c) the multi-level follower-like Bi2S3 structures.
M-H curves of (a) the comparative Bi2S3 sample; (b) the multi-level hollow Bi2S3 spheres and (c) the multi-level follower-like Bi2S3 structures.