‘Promoting Chemistry Applied to World Needs‘ webinar series

The total volume of water on earth is constant at 10²¹ liters. India has 4% of the global fresh-water resources with ~20% of the global population. Therefore, majority of Indian sub-continent is suffering from acute water stress. Equitable access to clean potable water is both a direct, important target of United National Sustainable Development Goals (SDG 6) and simultaneously carries significance to several other SDGs (SDG 3,7,13,15). Therefore, sustainable, cost-effective and affordable recovery of freshwater from contaminated water feedstock is the need of the hour to ensure it equitable access.

Solar-thermal interfacial evaporation offers immense and hitherto untapped potential for energy-efficient, sustainable freshwater production. However, fundamental challenges in materials and system-design result in low water evaporation rates (Rw < 1-2 kgm^-2h^-1) and even lower solar-freshwater productivity (SWP). Further, the lack of thermally and chemically stable materials that can operate in extreme salinities such as seawater without fouling or degrading is a major bottleneck that limits the wider adaptation of the technology.

This Talk by Chandramouli Subramaniam (Department of Chemistry, Indian Institute of Technology Bombay) would describe an ultra-thin, porosity-engineered polymeric scaffold (poly-HIPE, PH) that is anisotropically coated with nanostructured carbon florets (NCF) to deliver high solar-thermal conversion efficiency (η-STC = 84%), excellent Rw (6.5 kgm^-2h^-1) and exceptional SWP (3.5 Lm^-2h^-1) from sea-water. A few salient features of the material are

• Thinnest such membrane with no-signs of fouling over 30 days in sea-water, achieving
• Salt-rejection of ~95% with facile reusability for over 30 days,
• Producing freshwater of ~20 liters per m² area per day at
• Lowest CO₂ footprint (< 3 W/L, ~3 g /L)

Fundamental insights of materials-design to address the exothermic water-evaporation step that are synergized with systems-design approaches to achieve these key performance indices would be discussed.

September 24th from 8-9 a.m. EDT / 12-1 p.m. GMT

Zoom link: https://us06web.zoom.us/j/84303130066

References

1. Adv. Energy Mater., 2021, 11, 2003626
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3. ACS Appl. Mater. Interfaces, 2022, 14, 13271
4. ACS Sus. Chem. Eng. 2021, 9, 7792
5. ACS Appl. Mater. Interfaces, 2020, 12, 42669
6. ACS Appl. Nano Mater. 2019, 3, 468
7. ACS Appl. Mater. Interfaces, 2020, 13, 7969
8. npj clean water, 2023, 6, 75
9. ACS Appl. Mater. Interface, 2023, 15, 43810
10. Renewable Energy, 2023, 217, 119168
11. Indian Patent Application 202021042432, PCT/IN2022/051059

This is the 4th installment of the webinar series, “Promoting Chemistry Applied to World Needs” presented by Beyond Benign and IUPAC Chemrawn. If you haven’t already registered for this free series, RSVP here! https://buff.ly/4Gck2pv

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