Title Page
Contents
Abstract 8
1. Introduction 9
2. Experimental 12
2.1. Materials synthesis 12
2.2. Materials Characterization 12
2.3. Electrocatalytic Measurements 13
3. Results and discussion 15
3.1. Synthesis and characterization of CoFe₂O₄/β-Ni(OH)₂ 15
3.2. Electrochemical measurements 23
4. Conclusions 32
5. References 33
Table 1. Comparison of OER performance parameters of the synthesized samples 28
Table 2. Comparison of the OER activity between CoFe₂O₄/β-Ni(OH)₂ and... 30
Fig. 1. Schematic illustration of preparation of CoFe₂O₄/β-Ni(OH)₂. 15
Fig. 2. (a) Ellingham diagram of Gibbs free energy of formation (△G) of the... 16
Fig. 3. XRD patterns for (a) β-Ni(OH)₂ and (b) CoFe₂O₄. 17
Fig. 4. (a) XRD pattern, (b) SEM image, (c) low-magnification TEM, (d)... 18
Fig. 5. XPS spectra in the (a) Co 2p, (b) Fe 2p, and (c) Ni 2p regions of the... 20
Fig. 6. EELS spectra of (a) Co, (b) Fe, and (c) Ni of the samples. 21
Fig. 7. (a) Polarization curves of CoFe₂O₄/β-Ni(OH)₂, CoFe₂O₄, β-Ni(OH)₂,... 23
Fig. 8. Electrochemical characterization for various concentration of samples.... 25
Fig. 9. Electrochemical stability of CoFe₂O₄/β-Ni(OH)₂. (a)... 27