Investigation of Synthesis Conditions for Anodized Copper Oxide Layers: Properties and Applications.

• Grant number: 23/08259-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2023
• End date: June 30, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Ernesto Chaves Pereira de Souza
• Grantee: Felipe Benedito Soares
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 13/07296-2 - CDMF - Center for the Development of Functional Materials, AP.CEPID

Abstract

The search for new nanostructured materials spans various scientific fields, including medicine, optoelectronics, acoustics, photonics, sensors, and catalysis. Metallic copper is an excellent component for alloys due to its exceptional electrical and thermal conductivity, mechanical strength, and corrosion resistance. Electrochemical anodization is a surface treatment process that enables the creation of nanostructures on metal surfaces. Copper oxide nanostructures, with their low cost, non-toxicity, and low band-gap value, hold great promise for numerous applications.The synthesis conditions can be adjusted by modifying electrolyte concentration, temperature, applied potential, and anodization time. Additionally, the incorporation of copper salts in the electrolyte can influence nanostructure formation. The quality of the oxide layer depends on factors such as electrolyte composition, temperature, current, and treatment duration. Selecting these factors carefully is crucial for obtaining nanostructures with desired properties.During copper anodization, surface oxidation occurs as an electric current passes through an appropriate electrolyte solution. The quality of the resulting oxide layer depends on electrolyte composition, temperature, current, and treatment time. The electrolyte's composition is critical, as it must provide necessary ions and maintain a suitable pH. Commonly used electrolytes include sulfuric acid, phosphoric acid, and alkaline cyanide solutions. Maintaining the solution temperature within the optimal range of 20-25°C is crucial. The applied current directly affects oxide layer thickness and must be adjusted based on desired thickness and metal surface condition. Maintaining a low pH (acidic) is preferred, achieved using sulfuric acid or phosphoric acid, as they provide an adequate amount of H+ ions for rapid and uniform oxide layer formation. However, excessively low pH can lead to a porous and unstable oxide layer. Precise pH adjustment is essential to ensure efficient anodization and prevent the formation of a porous oxide layer. Treatment duration also influences oxide layer quality, with longer times resulting in thicker layers but potentially compromising adhesion through increased porosity. Determining the ideal duration requires empirical testing for each electrolyte and desired layer thickness.In summary, achieving uniform and adherent copper oxide layers through anodization is a complex process requiring careful adjustment of treatment conditions. The selection of appropriate electrolytes, temperature, current, and treatment time is critical to ensure oxide layer quality. Studying the synthesis conditions of anodized copper oxide layers is vital for several reasons. It enables the production of consistent and predictable oxide layers, crucial for electronics, microfabrication, and materials engineering. Furthermore, anodized copper oxide layers possess unique properties such as high hardness, corrosion resistance, and catalytic activity, making them suitable for various applications. Understanding the conditions affecting these properties is essential for designing copper oxide layers that meet specific application requirements. Thus, this project aims to investigate the optimal electrochemical anodization conditions for forming copper oxide nanostructures with potential applications in diverse fields.