Palladium hexadecylthiolate is shown to serve as a negative-tone direct-write electron resist to produce nanopatterns down to 30 nm. The written patterns do not deviate much from the precursor in composition, while a post-treatment at 230 degrees C in air produced metallic Pd nanowires with residual carbon less than 10% and resistivity close to the bulk value, a desirable property of interconnects in nanocircuitry. The as-written patterns contain small nanocrystals (<5 nm) in a hydrocarbon matrix, which upon annealing aggregate to form well-connected networks of larger nanocrystals (5-15 nm), thus giving rise to metallic conductivity.

Conducting polymers that absorb three primary colors, red, green, and blue (RGB), were introduced with a yellow electrochromic polymer (Y) for the preparation of black electrochromic devices. Red poly(3-hexylthiophene) (P3HT) and blue poly(3,4-ethylenedioxythiophene) (PEDOT) were coated on one side of the electrode as a cathodically coloring electrochromic (EC) layer, while green poly(aniline-N-butylsulfonate) (PANBS) and yellow EC poly{[1,3-bis(9',9'-dihexylfluoren-20-yl)azulenyl]-alt-[2",7"-(9",9"-dihexylfluorenyl]} (PDHFA) were coated on the opposite electrode to complete a complementary EC device. The yellow PDHFA layer effectively compensated for absorption below 450 nm and above the 600 nm region, which was lacking in the RGB electrode. The resultant RGBY ECD provided a black color near the CIE black with L*, a*, and b* values of 32, -1.1, and 3.7, respectively, covering a broad absorption in the visible range in the colored state. The state of the black EC device was maintained, even after the electricity was turned off for 200 h, showing stable memory effect.

We report a catalyst-free synthesis of cantilevered carbon nanosheet extensions, or petals, from graphite fibers by microwave plasma CVD. Results reveal that the petals grow from the fiber surface layers while preserving graphitic continuity from fiber to the petals. Subtraction of Raman signatures from pristine and decorated fibers reveals a convolution of two underlying peaks at 2687 and 2727 cm−1 that are consistent with profiles of multilayer graphene flakes between 5 and 25 layers. Such structures offer the possibility of minimizing interfacial losses in transport applications, improved interactions with surrounding matrix materials in composites, and a route toward substrate independence for device applications.

For the first time, we report the synthesis of turbostratic carbon derived from tire waste with high surface area and its utilization as an electrode material in vanadium redox flow batteries (VRFBs). The tire waste carbon was initially subjected to acid demineralization followed by KOH activation wherein the carbon to KOH ratio was varied (1:1, 1:2, and 1:5), and the electrochemical performance toward VO2+/VO2 +, V3+/V4+, and V2+/V3+ redox reactions was investigated. The turbostratic nature of carbon derived from tire waste was confirmed by high-resolution transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. Brunauer–Emmett–Teller (BET) measurements revealed the surface area was as high as 875 m2·g–1 for the 1:5 KOH activated sample. The electrochemical performance of pretreated carbon (TW) and turbostratic carbon (1:1, 1:2, and 1:5) was compared by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge methods. Our results indicated that the 1:5 KOH activated electrode exhibited the highest surface area and performed much better than the other ratios in terms of overall electrochemical performance including high peak current, less peak potential difference, low polarization potential, small charge-transfer resistance, high charge–discharge capacity, high Coulombic efficiency, and high energy efficiency. Further, a full cell was fabricated and its electrochemical performance was tested. The results indicated impressive electrochemical performance with Coulombic efficiency as 87% at 10 mA·cm–2 along with stable cycling behavior up to 200 cycles, thus signifying the tire waste derived turbostratic carbon offers great promise as high-performance electrodes for VRFB applications.

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Nanocrystalline metallic Pd films have been produced by thermolysis of Pd hexadecanethiolate deposited on a Si surface. The particle size was in the range of 50-60 nm based on electron and atomic force microscopy. The Pd surface produced was found to be surface-enhanced Raman scattering (SERS) active with an enhancement factor of approximately 10(5). The electron-resist behavior of Pd thiolate is exploited in conceptualizing a prototype chip with patterned Pd regions that are SERS active, called "SERS bits", which host different biomolecules.

Along with the ability to form desired architectures at the nanoscale, maximizing the enhancement factor of a Raman signal is of primary importance in a rational design of a surface enhanced Raman scattering (SERS) substrate. Here, we report how a layer of carbon on Si(100) substrate can assist and tune the formation of nanogranular gold in an electroless deposition process. It is demonstrated that Au deposited on an optimized thickness of carbon layer (∼90 nm) leads to a maximum enhancement factor of 107 with thiophenol as the probe molecule. Having characterized the substrates with AFM, XPS, and optical profilometry, their performance in SERS was tested using rhodamine 6G, hemoglobin, myoglobin, adenosine triphosphate, and adenine. In addition, the substrates are shown to be stable in the temperature range 123−433 K.

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