fig1

Figure 1. (A) XPS surface survey scan and high-resolution O 1s, N 1s, Fe 2p and Ni 2p spectra of Ni₂Fe₁@PANI-KOH900. (B) XRD patterns of Ni₂Fe₁-900, Ni₂Fe₁ NPN, Ni₂Fe₁@PANI-900 and Ni₂Fe₁@PANI-KOH900. (C) Schematic illustration of synthesis procedure for Ni₂Fe₁ NPN, Ni₂Fe₁@PANI-900 and Ni₂Fe₁@PANI-KOH900. (D) TEM (1), SAED (2) and HADDF-STEM (3) images of Ni₂Fe1@PANI-KOH900. Reproduced with permission. Copyright 2019, Royal Society of Chemistry^[48].