fig2
Figure 2. XPS spectra for N1s of (A) HCP-PNTL-A, (B) HCP-PNTL-Co-A, (D) HCP-PNTL-B and (E) HCP-PNTL-Co-B; Co2p of (C) HCP-PNTL-Co-A and (F) HCP-PNTL-Co-B. XPS: X-ray photoelectron spectroscopy; HCP: hypercrosslinked polymer; PNTL: 1,10-phenanthroline.