fig2

Figure 2. (A) XRD patterns of ZIF-8, MWCNTs, ZIF-8@MWCNTs-1, ZIF-8-C, Se@ZIF-8-C@MWCNTs-1, and selenium. (B) Nitrogen adsorption and desorption isotherms of ZIF-8-C, Se@ZIF-8-C, ZIF-8-C@MWCNTs-1 and Se@ZIF-8-C@MWCNTs-1. (C) TGA curves of Se@ZIF-8-C and Se@ZIF-8-C@MWCNTs-1 under nitrogen with a rate of 5 °C min^-1. XPS spectrum of Se@ZIF-8-C@MWCNTs-1: (D) Survey scan; (E) C1s; and (F) Se3d.