Chuanbao Cao and colleagues note that carbon is a key component in commercial Li-ion energy storage devices including batteries and supercapacitors. Most commonly, graphite fills that role, but it has a limited energy capacity. To improve the energy storage, manufacturers are looking for an alternative material to replace graphite. Cao’s team wanted to see if they could develop such a material using a sustainable source.
The researchers found a way to process natural silk to create carbon-based nanosheets that could potentially be used in energy storage devices. Their material stores five times more lithium than graphite can — a capacity that is critical to improving battery performance. It also worked for over 10,000 cycles with only a 9 percent loss in stability. The researchers successfully incorporated their material in prototype batteries and supercapacitors in a one-step method that could easily be scaled up, the researchers note.