Supercapacitors: Cellulose Nanocrystal Aerogels as Universal 3D Lightweight Substrates for Supercapacitor Materials (Adv. Mater. 40/2015)

An improved 3D energy‐storage device, constructed by trapping functional nanoparticles within the walls of a foam‐like structure made of cellulose nanocrystals is demonstrated by E. D. Cranston and co‐workers on page 6104. The resulting supercapacitor is lightweight and flexible with excellent capacitance retention, low internal resistance and fast charge–discharge rates. The front‐cover image is an artistic rendition of the device's internal structure (credit: Dr. Kevin G. Yager, Brookhaven National Lab).