Figure 5. Nanoporous carbon membranes as electrodes for supercapacitors.

(a) SEM image of the cross-section of a half-etched carbon/silica membrane, in which the silica is uniformly etched from the top of the membrane. (b) Cyclic voltametry curves of a 20 μm-thick membrane in a three-electrode system using 0.2 M K₂SO₄ as electrolyte. (c) Calculated volumetric capacitances of monolithic nanoporous carbon membranes. (d) A wafer with different electrode patterns after one-step lithography of silica-templated SU-8. The inset photograph shows a micro supercapacitor prototype fabricated using the same process as a nanoporous carbon membrane. The device has 8 interdigital fingers as electrodes, each finger is 320 μm wide and separated by 160 μm-wide space. (e) Cyclic voltametry curves of a micro supercapacitor using 0.2 M K₂SO₄ as electrolyte. (f) Calculated specific capacitances of the micro supercapacitor from cyclic voltametry curves.