Synthesis, Characterization and Electrocatalytic Studies of Bi-Metallic Oxides

Abstract

Owing to slow and complex sluggish kinetics of oxygen evolution reaction (OER) of water splitting, engineering an economical and stable material is a challenging task. Low over potential, high current density, and good reaction kinetics are deciding factors of an good catalyst for OER.Considering these factors, a e ort was made to synthesize the industrious, e cacious and e ective catalysts. In the rst scheme, Antimony-Lead bimetallic oxide was synthesized by dual source precursor method followed by di erent optimizations factors such as annealing temperatures. In second scheme , the antimony trioxide was synthesized by precipitation method by optimizing the annealing temperatures. With the help of AACVD (aerosol assisted chemical vapour deposition ) FTO substrates based thin lms were obtained and tested for electrochemical splitting of water. The as-synthesized materials were also characterized using [powder X-ray di raction technique(XRD), Scanning Electron Microscopy (SEM), Energy Dispersive spectroscopy (EDX), and Raman spectroscopy. It was found that highly crystalline Sb2O5-Pb3O4 was synthesized and its crystallinity varied with di erent factors. Sb2O5- Pb3O4 composite and Sb2O3 were then employed for electrocatalytic water splitting particularly oxygen evolution reaction. The Sb2O5-Pb3O4 compos ite was synthesized through dual precursor method with 3 hours of annealing reaction at di erent temperatures. The Sb2O5-Pb3O4 composite annealed at 500°C manifested the highest current density of 15 mA cmð€€€2 with onset potential of 1.39 V vs Reverse Hydrogen Electrode (RHE). The over potential at 10 mA of current was about 220 mV with a least tafel slope of 50 mV decð€€€1 with good stability and least charge transfer resistance of only 455.7 ohm. Similarly, Sb2O3 synthesized through precipitation method at 500°C annealing temperature re ected exceptional results. Antimonious oxide exhibited current density of 8 mAcmð€€€2 at with onset potential of 1.55 V vs Reverse Hydrogen Electrode (RHE). The over potential for 1 mAcmð€€€2 current density was found 370 mV with least tafel slope of 70 mv decð€€€1, and least charge transfer resistance of only 1.9x106 ohm. Stability and durability was checked and found no signi cant degradation was observed. Further research and modi cation in as-synthesized catalysts can be used on a commercial and industrial scale to meet the rising energy need.