Methane thermal decomposition is a promising technology for producing CO₂-free hydrogen. This study experimentally examines how temperature (1,000–1,400^oC) and residence time affect methane decomposition in a ceramic tubular reactor. The results show that both the methane conversion rate and hydrogen yield increased with temperature, reaching approximately 95% and 45%, respectively, at 1,400^oC. At lower temperatures (1,000–1,200^oC), residence time had a significant impact, while at higher temperatures (1,300–1,400^oC), temperature became the predominant factor. Additionally, the formation of C₂ hydrocarbons, particularly acetylene (C₂H₂), increased as residence time decreased, negatively affecting both methane conversion and hydrogen yield. Analysis of the solid carbon by-products identified two distinct forms: amorphous, spherical carbon black particles and a semi-graphitic, crystalline carbon film. These findings provide essential data for optimizing the conditions of methane thermal decomposition.

Among chemical coating methods, deposition using electrostatic spraying is commonly employed in coating processes to control the deposition rate, thickness, and properties of the formed materials. In this study, we considered the following variables: ring electrode, ring diameter (RD), ring voltage (RV), and nozzle-ring distance (NTR). Through experiments, we determined the atomization mode applied voltage, Sauter mean diameter (SMD), and SMD standard deviation of the nozzle. Additionally, we derived the voltage intensity and electric field along the axial direction using ANSYS maxwell to identify the optimal ring electrode atomization conditions.