“…They both exhibited a pair of spin–orbit bimodal signals, with Co 2p 3/2 and Co 2p 1/2 peaks of CoP/NC observed at 778.48 and 793.35 eV and ascribed to Co-P bonds in CoP/NC, with peaks observed at 781.84 and 797.63 eV and ascribed to Co-O bonds that may have resulted from surface oxidation, and with peaks observed at 785.93 and 802.62 eV and considered to be shake-up satellite peaks (indicated as “Sat”). 31,32 Compared with those of CoP/NC, the binding energy levels of the Co 2p 3/2 and Co 2p 1/2 peaks of 4.3% B-CoP/NC were negatively shifted by about 0.01 eV, attributed to the introduction of B atoms into CoP. In general, the ability of low-electronegativity B to absorb electrons is lower than that of P, which results in fewer electrons nearby the B atom and an increase in the electron density nearby the Co atom for the Co-B bond, which in turn would be expected to result in a relatively lower valence state of Co in 4.3% B-CoP/NC.…”