Djeffal is professor, University of Batna-2, Batna, Algeria. His contributions to materials science, solid-state devices and artificial intelligence (AI) have gained substantial research acclaim in the field of electronic device modeling and fabrication, specifically in the area of development of new high-performance and low cost microelectronic devices for renewable energy and environmental sensing applications, as evidenced by the number of citations for his published papers in a short span of time. In the context of microelectronic devices for renewable energy and environmental sensing applications, Djeffal has successfully developed new approaches and design techniques of microelectronic devices using soft-computing and AI-based methods. These approaches are now widely used by several scientific centers. He has published more than 280 journal articles and conference papers and is the author of some books and book-chapters in the field of photovoltaic devices/environmental sensors and soft-computing. Member of the African Academy of Sciences, he has received the Abdul Hameed Shoman Award for Arab Researchers and Microsoft-TWAS-AAS Award, among others.