Dr. Hairus Abdullah received his doctoral degree from the Department of Materials Science and Engineering, National Taiwan University of Science and Technology (NTUST), in 2016. He continued to serve as a postdoctoral fellow in the same department till 2019. Afterward, he became a visiting professor in the Department of Materials Science and Engineering, NTUST. In addition, he also supports academic and research activities at Universitas Prima Indonesia (UNPRI), Medan, Indonesia. His research interests are in photocatalysis (including hydrogen evolution reaction, hydrogenation of toxic species, antibacterial application), electrocatalysis, photoelectrocatalysis, and supercapacitors.