Abstract: The disclosed technology generally relates to energy storage devices, and more particularly to energy storage devices comprising frustules. According to an aspect, a supercapacitor comprises a pair of electrodes and an electrolyte, wherein at least one of the electrodes comprises a plurality of frustules having formed thereon a surface active material. The surface active material can include nanostructures. The surface active material can include one or more of a zinc oxide, a manganese oxide and a carbon nanotube.

Abstract: A printed energy storage device includes a first electrode, a second electrode, and a separator between the first and the second electrode. At least one of the first electrode, the second electrode, and the separator includes frustules, for example of diatoms. The frustules may have a uniform or substantially uniform property or attribute such as shape, dimension, and/or porosity. A property or attribute of the frustules can also be modified by applying or forming a surface modifying structure and/or material to a surface of the frustules. A membrane for an energy storage device includes frustules. An ink for a printed film includes frustules.

Abstract: The invention is a process wherein SO.sub.2 is absorbed in a concentrated solution of potassium citrate and the solution is reacted with H.sub.2 S at a temperature above the melting point of sulfur to form elemental sulfur. The reaction produces a solution lean in sulfur dioxide. SO.sub.2, in the form of a rich solution or a gas, can be introduced into the lean solution in order to inhibit post-formation of sulfur. This introduction of SO.sub.2 avoids a tendency for sulfur to form continually after the solution exits the reaction zone.

Abstract: A continuous process for the reduction of sulfur dioxide to sulfur in which a gas stream containing sulfur dioxide is contacted with a carbon source in the form of particulate coal at a temperature of at least 600.degree. C. in a plasma arc reaction zone generated by a rotating direct current arc.