Dewetting surfaces for environmental applications (11/11/22)

Speaker and Affliation:

Dr. Sriharitha Rowthu
Assistant Professor
Materials Engineering, IIT Gandhinagar

Speaker’s Biography

Dr. Sriharitha Rowthu is currently serving as an assistant professor in the Materials Engineering Discipline at IIT Gandhinagar. Also, she is a group leader of the Functional Materials Laboratory (FML) at IIT Gandhinagar, comprising of 2 postdoctoral researchers, 3 Ph.D. students, 2 M. Tech students, 1 JRF and 1 UG student. The group conducts research in the surface science and engineering domain, specifically in the fields of wetting, tribology, soft lithography, ceramics and powders processing. Dr. Sriharitha Rowthu pursued integrated dual degree (M.Tech. + B.Tech.) program in the Metallurgical and Materials Engineering department at Indian Institute of Technology (IIT) Madras, during 2006- 2011. Following that, she pursued her doctoral studies (Dec 2011-May 2016) at École polytechnique fédérale de Lausanne (EPFL) and jointly at Empa Thun, Switzerland. Later, she went to pursue her postdoctoral research work in the Laboratory for Nuclear Materials at Paul Scherrer Institute (PSI) in Switzerland. Dr. Sriharitha Rowthu has published 15 articles, 1 book chapter and 3 more articles are under review. As a principal/co-principal investigator, she has raised a total funding of Rs. 2.5 Crore so far, from several funding agencies namely DST, SERB, Gujarat State Archaeology, and IIT Gandhinagar. She has been recipient of several national and international awards for excellence in poster and oral presentations at several forums, including the prestigious E-MRS, NMD-ATM, EUROCORR etc. as well as research excellence award by IIT Gandhinagar for a period of 3 years (Dec 2019-Dec 2022). Recently, Dr. Sriharitha Rowthu has been recognized for her excellence in teaching contributions by IIT Gandhinagar for the “Corrosion and degradation of Materials” course taught during Jan-May 2022. More details including the achievements of her advisees can be found at


11th November, 2022 (Friday), 11:00 AM (India Standard Time)


KPA Auditorium


Non-wetting surfaces can be useful in several sectors such as marine, biomedical, paint, food industries etc. They are primarily prepared by mimicking natural surfaces such as Lotus leaves, Shark skin, bird feathers, flower petals, Nepenthes Pitcher Plant etc. Typically, the surface chemistries and surface topologies are carefully controlled to tailor the surface wettability. Globally, researchers are focusing on the fabrication of novel non-wetting surfaces to achieve anti-frosting, anti-icing, anti- bacterial surfaces etc. However, most of them have utilized protruding (positive) textures or simply untextured (referred to as flat) surfaces. In this talk, the emphasis will be given to compare the performance of dimples (negative) on the non-wetting properties with that of the positive textures and untextured surfaces. For this, the silicone oil coated textured PDMS surfaces are employed. The static contact angles, dynamic contact angles and slide-off angles of water drops were measured as a function of oil film thickness and thermodynamic models were adapted to explain the observations. Also, the shear drainage of the lubricant and the normal adhesion of the water drops atop these positively textured, negatively textured and flat, oil coated surfaces were quantitatively measured. They reveal that the negative textures outperform the positive textures and flat surfaces. Additionally, these textures have shown high promise in terms of lubricant retention in submerged sea-water flowing conditions as tested up to 7 days. Further, the use of non-wetting surfaces for sanitation applications, marine applications and food industries will be discussed briefly.