Aero cellulose. Coloured scanning electron micrograph (SEM) showing the fibres within the structure of aero cellulose. This highly porous form of cellulose forms a material with a much larger surface area, higher porosity and lower density than that of normal cellulose. It is therefore suitable for use in applications such as filtration and as hydrogen storage in super capacitors, or as a lightweight biodegradable material structure. Magnification: x6700, when printed 10 centimetres wide.