#loofahs

Access to clean water is being strained as the human population increases and contamination impacts freshwater sources. Devices currently in development that clean up dirty water using sunlight can only produce up to a few gallons of water each day. But now, researchers in ACS Central Science report how loofah sponges inspired a sunlight-powered porous hydrogel that could potentially purify enough water to satisfy someone's daily needs—even when it's cloudy.

Previously, researchers have suggested that sunlight-driven evaporation could be a low-energy way to purify water, but this approach doesn't work well when it's cloudy. One solution could be temperature-responsive hydrogels, specifically poly(N-isopropyl acrylamide) (PNIPAm), that switch from absorbing water at cooler temperatures to repelling it when heated. However, conventional PNIPAm gels can't generate clean water fast enough to meet people's daily needs because of their closed-off pores. Conversely, natural loofahs, which many people use to exfoliate in the shower, have large, open and interconnected pores. So, Rodney Priestley, Xiaohui Xu, and colleagues wanted to replicate the loofah's structure in a PNIPAm-based hydrogel, yielding a material that could rapidly absorb water at room temperature, and rapidly release purified water when heated by the sun's rays under bright or cloudy conditions.

🎀 various kidcore stims 🌈