fig3

Figure 3. (A) XRD of the as-synthesized Ni₃S₂@NF, Co_xNiS@NF, and NF. (B) Corresponding enlarged XRD patterns. (C) XPS spectra of Ni 2p for Co_0.4NiS@NF and Ni₃S₂@NF. In situ Raman spectra of Co_0.4NiS@NF electrodes during (D) OER (1.0 M KOH) and (E) HMFOR (1.0 M KOH with 50 × 10^-3 M HMF) under increasing potential from OCP to 1.6 V. (F) In situ Raman spectra of Co_0.4NiS@NF electrodes during OER (1.0 M KOH) and half-way injected HMF (10 × 10^-3 M HMF) under 1.45 V. (G) Linear sweep voltammetry (LSV) curve. (H) Tafel plots. (I) Nyquist. Reproduced with permission^[70]. Copyright 2022, Wiley.