Figure 3
From: Synthesis of lignin-derived nitrogen-doped carbon as a novel catalyst for 4-NP reduction evaluation
XPS spectra of NC at different annealing temperature and g-C3N4/lignin ratio. (a) N 1 s scans of NC at different temperature. (b) XPS spectra of NC at different g-C3N4/lignin ratio. (c) Nitrogen content of each type of N species at different temperature. (d) Element content of NC samples at different g-C3N4/lignin ratio.
