IIT Bombay Develops Lotus Leaf-Like Solar Evaporators for Sustainable Desalination

By siliconindia  |  Wednesday, 16 April 2025, 11:55:29 AM IST

IIT Bombay Develops Lotus Leaf-Like Solar Evaporators for Sustainable Desalination
In a breakthrough that could significantly advance sustainable water purification, scientists at the Indian Institute of Technology (IIT) Bombay have developed a graphene-based solar evaporator inspired by the self-cleaning properties of lotus leaves. The innovation addresses the global freshwater scarcity crisis, offering a promising solution for desalination, especially in landlocked regions.
Led by Prof. Swatantra Pratap Singh, the research team developed a novel material named Dual-Sided Superhydrophobic Laser-Induced Graphene (DSLIG) evaporator. Designed to purify saltwater using both solar and electric heating, DSLIG ensures continuous water treatment regardless of sunlight availability. The hybrid heating approach allows the material to function efficiently even under low-light or cloudy conditions through Joule heatingn an electrical heating method.
A key feature of DSLIG is its superhydrophobic nature, which mimics the lotus leaf effect. This property enables water droplets to roll off the surface without wetting it, minimizing salt accumulation and maintaining the evaporator’s efficiency over time. “The primary goal of our work was to create a superhydrophobic surface, exhibiting the lotus effect, capable of functioning with both solar and Joule heating”, said Prof. Singh.
To fabricate the material, the researchers coated a polymer called polyvinylidene fluoride (PVDF) onto one side of a thin poly(ether sulfone) (PES) layer. Using laser engraving technology, they inscribed a graphene pattern on the PVDF surface, giving it the desired lotus-like texture and characteristics. Laboratory tests confirmed that DSLIG resists salt deposition and performs exceptionally well under both solar and electric heating, even in highly saline water conditions.
What sets this innovation apart is its sustainability profile. DSLIG offers a low carbon footprint, low toxicity, and cost-effective scalability, making it suitable for large-scale desalination and industrial wastewater treatment.
As freshwater resources grow scarcer due to climate change and population growth, such technological solutions are vital. With only about 0.05% of Earth’s freshwater readily accessible, efficient and sustainable desalination methods like DSLIG could pave the way for global water security. IIT Bombay’s advancement marks a crucial step toward clean water access and energy-efficient desalination systems.

ON THE DECK

Top Banner

Related Articles