Fig. 1.

Characterization of BSNs. (A) Diagram of the preparation of BSNs through sol-gel soft template method. (B) XRD patterns of the prepared four types of BSNs. The broad peaks indicated the amorphous structure of BSNs. (C) FTIR spectrum of BSNs. The peaks at 1060 and 805 cm⁻¹ were attributed to the vibration of [Si–O–Si] and the peaks at 1393 and 942 cm⁻¹ were associated with the vibration of [B–O–B]. (D) TEM images of the prepared BSNs. They showed BSNs were mesoporous dispersed nanoparticles which are distributed around 50 nm in particle size; scale bar: 50 nm. (E) Cu 2p XPS spectrum of BSNs-Cu. (F) Mn 2p XPS spectrum of BSNs-Mn. (G) Cu 2p XPS spectrum of BSNs-Cu-Mn. (H) Mn 2p XPS spectrum of BSNs-Cu-Mn. The XPS spectrums of BSNs confirmed that copper existed in the form of Cu(Ⅱ); most manganese existed in the form of Mn(Ⅲ), and a small amount existed in the form of Mn(Ⅳ).