Physical and chemical mechanisms of hydrophobicity of nanoparticle membranes (Mg+Al2 O 3 ) Wahyudia , R. Subagyob,*, F. Gapsaric a Department of Mechanical Engineering, Faculty of Engineering,Universitas Muhammadiyah Yogyakarta, Brawijaya street, Kasihan, Bantul, Yogyakarta, 55183, Indonesia b Mechanical Engineering Department, Engineering Faculty, University Lambung Mangkurat, Jenderal Achmad Yani Street KM 35.5, Banjarbaru, South Kalimantan, 70714, Indonesia c Mechanical Engineering Department, Engineering Faculty, University Brawijaya, Veteran street No. 16, Malang, East Java, 65145, Indonesia * Corresponding e-mail address: rachmatsubagyo@ulm.ac.id ABSTRACT Purpose: Investigate the hydrophobic, superhydrophobic and hydrophilic properties of Alumina (Al2 O 3 ) and Magnesium (Mg) nanoparticles. Design/methodology/approach: This research was conducted by SEM-EDX analysis of Magnesium and Alumina nanoparticles, observation of gas bubbles when droplets of water contact with membrane surfaces, measurement of surface roughness and detection of Hydrogen gas production using Gas Chromatography. There are eleven compositions (Al2 O 3 :Mg) membranes used in this study, namely: (0:100; 10:90; 20:80; 30:70; 40:60; 50:50; 60:40; 70:30; 80:20; 90:10; and 100:0). Findings: Successfully found an alloy membrane between Alumina (Al2 O 3 ) and Magnesium (Mg) nanoparticles in the composition of Mg:Al2 O 3 (0:100%) having Hydrophobic properties; Mg:Al2 O 3 (50:50%) has Superhydrophobic properties and Mg:Al2 O 3 (100:0%) has hydrophilic properties. Three conditions occur when H2 O droplets come in contact with the membrane layer, namely: hydrophobic conditions when the trapped gas pressure is smaller than the droplet pressure. Superhydrophobic conditions when the trapped gas pressure is equal to the droplet pressure. Hydrophilic conditions occur when the trapped gas pressure is greater than the droplet pressure. Research limitations/implications: This research is limited to the hydrophobic nature of Nano Alumina (Al2 O 3 ) and Magnesium (Mg) membrane particles. Practical implications: Superhydrophobic properties are very suitable to be applied to membranes that are useful for destiny. Originality/value: The novelty of this study is to find the right mixture of nanoparticles of Alumina and Magnesium in a composition that is capable of creating hydrophobic, superhydrophobic and hydrophilic properties. Keywords: Hydrophobic, Superhydrophobic, Hydr

Abstract

Purpose: Investigate the hydrophobic, superhydrophobic and hydrophilic properties of Alumina (Al2 O 3 ) and Magnesium (Mg) nanoparticles. Design/methodology/approach: This research was conducted by SEM-EDX analysis of Magnesium and Alumina nanoparticles, observation of gas bubbles when droplets of water contact with membrane surfaces, measurement of surface roughness and detection of Hydrogen gas production using Gas Chromatography. There are eleven compositions (Al2 O 3 :Mg) membranes used in this study, namely: (0:100; 10:90; 20:80; 30:70; 40:60; 50:50; 60:40; 70:30; 80:20; 90:10; and 100:0). Findings: Successfully found an alloy membrane between Alumina (Al2 O 3 ) and Magnesium (Mg) nanoparticles in the composition of Mg:Al2 O 3 (0:100%) having Hydrophobic properties; Mg:Al2 O 3 (50:50%) has Superhydrophobic properties and Mg:Al2 O 3 (100:0%) has hydrophilic properties. Three conditions occur when H2 O droplets come in contact with the membrane layer, namely: hydrophobic conditions when the trapped gas pressure is smaller than the droplet pressure. Superhydrophobic conditions when the trapped gas pressure is equal to the droplet pressure. Hydrophilic conditions occur when the trapped gas pressure is greater than the droplet pressure. Research limitations/implications: This research is limited to the hydrophobic nature of Nano Alumina (Al2 O 3 ) and Magnesium (Mg) membrane particles. Practical implications: Superhydrophobic properties are very suitable to be applied to membranes that are useful for destiny. Originality/value: The novelty of this study is to find the right mixture of nanoparticles of Alumina and Magnesium in a composition that is capable of creating hydrophobic, superhydrophobic and hydrophilic properties.