Nanoimprint lithography is proposed as a highly versatile method for the production of nanostructured supercapacitors (micro-supercapacitors, MSC). Liquid sucrose- and lignin-precursor printing produces patterns with high quality and a line width down to 500 nm. The liquid-carbon-precursor NIL-printing approach enables nitrogen doping to achieve an increased supercapacitor performance for aqueous electrolytes (Li2SO4). The lines are interconverted into nanoporous carbon materials (d ≈ 1 nm) with high specific surface area (>1000 m2 g-1) to form stable structures reaching specific resistivities as low as ρ = 3.5 × 10-5 Ωm and capacitances up to 7 F cm-3.

A novel three-electrode electrolyte supercapacitor (electric double-layer capacitor [EDLC]) architecture in which a symmetrical interdigital "working" two-electrode micro-supercapacitor array (W-Cap) is paired with a third "gate" electrode that reversibly depletes/injects electrolyte ions into the system controlling the "working" capacity effectively is described. All three electrodes are based on precursor-derived nanoporous carbons with welldefined specific surface area (735 m 2 g −1 ). The interdigitated architecture of the W-Cap is precisely manufactured using 3D printing. The W-Cap operating with a proton conducting PVA/H 2 SO 4 -hydrogel electrolyte and high capacitance (6.9 mF cm −2 ) can be repeatedly switched "on" and "off ". By applying a low DC bias potential (−0.5 V) at the gate electrode, the AC electroadsorption in the coupled interdigital nanoporous carbon electrodes of the W-Cap is effectively suppressed leading to a stark capacity drop by two orders of magnitude from an "on" to an "off " state. The switchable micro-supercapacitor is the first of its kind. This general concept is suitable for implementing a broad range of nanoporous materials and advanced electrolytes expanding its functions and applications in future. The integration of intelligent functions into EDLC devices has extensive implications for diverse areas such as capacitive energy management, microelectronics, iontronics, and neuromodulation.

High-resolution interdigital micro-supercapacitor (MSC) devices are produced by one-step printing of liquid carbon precursors based on renewable resources. A piezo-driven micro-pipetting system allows precise positioning of the ink, offering a high degree of variability in terms of geometric supercapacitor designs. The printed precursor structures were directly converted into nanoporous carbon materials by pyrolysis at 900 °C. A hydrogel electrolyte based on PVA/H 2 SO 4 was used to form quasi-solid-state MSCs. Stable structures with an ohmic serial resistance of around 540 Ω and capacitance up to 151 F cm −3 (3.9 mF cm −2 ) could be produced via additional nitrogen doping of the nanoporous carbon. The capacitance retention of piezoelectric-printed structures after 10,000 cycles remains as high as 96%.

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The isolation of 2D nanosheets of layered metal-organic frameworks (MOFs) has become an active research field, due to the various advantages resulting from shape anisotropy. The most sophisticated method to...

A highly energetic carbon precursor suitable for soft lithographic processing based on acetylene dicarboxylic acid is presented. High-resolution micro-supercapacitors with line width down to 500 nm are produced using the...

A three‐step fabrication process for optically transparent, conducting ITO thin films with an intrinsic inverse opal structure is described. The preparation is based on colloidal crystal templating using polystyrene microspheres (100 nm–600 nm). For the realization of varying periodicities in this structure, different sphere sizes were assembled to monolayers on a substrate by spin coating and infiltrated afterwards similarly. The influence of rotation parameters as well as dispersion concentration was studied. Using this approach different geometries of the surface are accessible by systematically varying the rotation parameters and infiltration volume. The thin films show excellent anti‐reflection behavior, good transmission (>80% in the visible range) as well as a low resistance of 200 Ω/sq compared to other porous ITO interfaces. The properties are very promising for several optoelectronic applications such as in‐ or out‐coupling structures in solar cells and organic light emitting diodes.

Ac ombination of soft lithographic printing and soft templating has been used to fabricate high-resolution interdigitatedm icro-supercapacitors (MSC). Surfactant-assisted self-assembly produces high surface area orderedm esoporous carbons(490 m 2 g À1). For the first time, such precursors have been printed by nano-imprint lithography as microdevices with al ine width of only 250 nm and as pacing of only 1 mm. The devices are crack-free with low specific resistance(1.2 10 À5 Wm) and show good device capacitance up to 0.21 Fcm À3 .