Alumina supported copper oxide nanoparticles (CuO/Al2O3) as high-performance electrocatalysts for hydrazine oxidation reaction

• Published in: Chemosphere (Oxford) Vol. 315; p. 137659
• Main Authors: Khan, Safia, Shah, Syed Sakhawat, Janjua, Naveed Kausar, Yurtcan, Ayse Bayrakçeken, Nazir, Muhammad Tariq, Katubi, Khadijah Mohammedsaleh, Alsaiari, Norah Salem
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2023
• Subjects: Aluminum Oxide - chemistry; Copper - chemistry; Copper oxide (CuO); Cyclic voltammetry; Electrocatalyst; Gamma alumina (γ-Al2O3); Hydrazine oxidation reaction (HzOR); Hydrazines; Impedance spectroscopy; Impregnation; Nanoparticles; Nanoparticles - chemistry; Oxides; Nanoparticles; Cyclic voltammetry; Impregnation; Electrocatalyst; Copper oxide (CuO); Impedance spectroscopy; Hydrazine oxidation reaction (HzOR); Gamma alumina (γ-Al2O3); Gamma alumina (γ-AlO)
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2022.137659

Direct hydrazine liquid fuel cell (DHFC) is perceived as effectual energy generating mean owing to high conversion efficiency and energy density. However, the development of well-designed, cost effective and high performance electrocatalysts is the paramount to establish DHFCs as efficient energy generating technology. Herein, gamma alumina supported copper oxide nanocatalysts (CuO/Al2O3) are synthesized via impregnation method and investigated for their electrocatalytic potential towards hydrazine oxidation reaction. CuO with different weight percentages i.e., 4%, 8%, 12%, 16% and 20% are impregnated on gamma alumina support. X-ray diffraction analysis revealed the cubic crystal structure and nanosized particles of the prepared metal oxides. Transmission electron microscopy also referred to the cubic morphology and nanoparticle formation. Electrochemical oxidation potential of the CuO/Al2O3 nanoparticles is explored via cyclic voltammetry as the analytical tool. Optimization of conditions and electrocatalytic studies shown that 16% CuO/Al2O3 presented the best electronic properties towards N2H2 oxidation reaction. BET analysis ascertained the high surface area (131.2546 m2 g1) and large pore diameter (0.279605 cm³ g−1) for 16% CuO/Al2O3. Nanoparticle formation, high porosity and enlarged surface area of the proposed catalysts resulted in significant oxidation current output (600 μA), high current density (8.2 mA cm−2) and low charge transfer resistance (3.7 kΩ). Electrooxidation of hydrazine on such an affordable and novel electrocatalyst opens a gateway to further explore the metal oxide impregnated alumina materials for different electrochemical applications. [Display omitted] •Alumina supported copper oxide nanoparticles are successfully synthesized via impregnation method.•These electrocatalysts displayed excellent stability and activity towards hydrazine oxidation reaction.•16% CuO/Al2O3 is found to be the best composition of the series owing to highest current density and rate constant.•Electrochemical parameters complimented the physicochemical properties of the catalysts.