Reuseable nanosponges could soak up oil spills

A new wonder material that has the ability to repeatedly absorb oil spilled in water has been touted by researchers in the US.

The Rice University team, in collaboration with researchers from Penn State University, found that adding a dash of boron to carbon while creating nanotubes turned them into solid, spongy, reusable blocks with remarkable capabilities. According to researcher Daniel Hashim, a graduate student at Rice, the blocks are both superhydrophobic - meaning they repel water allowing them to float extremely well, and oleophilic – meaning they have a strong affinity for oils. The nanosponges, which are more than 99% air, also conduct electricity and can easily be manipulated with magnets. To demonstrate its capabilities, the sponge was dropped into a dish of water with used motor oil floating on top, which it soaked it up. Hashim then put a match to it, burned off the oil and returned the sponge to the water to absorb more. The robust sponge, he says, can be used repeatedly and withstand up to 10,000 compressions. Remarkably, it can also absorb more than a hundred times its weight in oil also and even store it for later retrieval. "These samples can be made pretty large and can be easily scaled up," Hashim noted. "They're super low density, so the available volume is large. That's why the uptake of oil can be so high." The researchers have high hopes for the material's environmental applications. "For oil spills, you would have to make large sheets of these or find a way to weld sheets together," Hashim commented. "Oil spill remediation and environmental cleanup are just the beginning of how useful these new nanotube materials could be. "For example, we could use these materials to make more efficient and lighter batteries. We could use them as scaffolds for bone tissue regeneration. We even could impregnate the nanotube sponge with polymers to fabricate robust and light composites for the automobile and plane industries." Hashim believes the nanosponges could also work as membranes for filtration. "I don't think anybody has created anything like this before," he concluded. "It's a spectacular nanostructured sponge."