Fabrication and Characterization of Hydrophobic Porous Metallic Membranes for High Temperature Applications

• Main Authors: Sara Claramunt, Muhammad Khurram, Walther Benzinger, Manfred Kraut, Roland Dittmeyer
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Processes
• Subjects: porous metal membrane; hydrophobic; plasma enhanced—chemical vapor deposition; amorphous carbon layer; dip coating; FAS
• Online Access: https://www.mdpi.com/2227-9717/9/5/809

Hydrophobic porous metallic membranes can be integrated in a microreactor for in situ separation of steam at high temperatures. This study investigates the fabrication and characterization of hydrophobic coatings on metallic substrates. Two different coating methods were explored: (1) Plasma Enhanced—Chemical Vapor Deposition (PE-CVD) to form amorphous carbon silicon-doped a-C:H:Si:O thin films and (2) Direct Immersion in fluoroalkyl silane (FAS-13) solution using dip coating to form Self-Assembled Monolayers. The results on wettability as well as SEM images and EDS/WDS analyses indicate that the coated sintered stainless steel membranes are adequate as hydrophobic surfaces, maintaining the porosity of the substrate and withstanding high temperatures. Especially the FAS-13 coating shows very good resistance to temperatures higher than 250 °C. These findings are of special significance for the fabrication of porous metal membranes for separation of steam in high temperature applications.