We examine possible mechanisms for graphitization at dislocation cores in diamond, both as an explanation for brown coloration in natural brown diamond and as a model for annealing in amorphous carbon materials. We find a metastable structure for the 90 • partial dislocation core where bonds are broken in both single-and double-period structures leading to a row of paired sp 2 C atoms. We examine the effect of hydrogen and other impurities on this core structure both through direct interaction and potential charging effects. We also investigate a mechanism for progressive aromatization through the migration and aggregation of 30 • partial dislocations.

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Conductive polymer (CP)–elastomer composites have been proposed as an alternative to the metals conventionally used for bioelectronic devices. Being softer and more stretchable than metals such as platinum and gold, they can mitigate the adverse effects associated with mechanical mismatch and fatigue failure. Such composites are conventionally made by embedding CP particles inside an elastomeric matrix. However, to achieve such a structure, a high CP loading that reaches a percolation threshold is required. High percolation thresholds lead to the degradation of mechanical properties. This study presents an alternate approach designed to reduce the CP content while maintaining conductivity through the matrix. A poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) composite was produced by filling a CP aerogel with polydimethylsiloxane (PDMS). This approach successfully formed a stretchable, conductive material, with only 1.8 wt. % CP. While elastic behavior was observed at low strain, the composite displayed plastic deformation at high strain (>20%). Future improvements will focus on the modification of the PEDOT:PSS–PDMS interface, to improve interaction of the polymer components and, hence, mechanical stability within the construct.

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The paper discusses the issues concerning producing of compact hydrogen resources for fuel cells. The suggested alternative is implementation of the reaction of activated aluminum with water. In the paper, as an activator Ga-In liquid eutectic alloy is used. One of the main features of the study is using various industrial aluminum alloys as basic materials. With the help of scanning electron microscopy investigation with local element analysis the process of activation of technical alloy on aluminum basis treated by Ga-In eutectic is studied. Such processing leads, on the one hand, to the intense embrittlement, on the other hand -to the sharp increase in material chemical activity in relation to water with hydrogen emission. It is demonstrated, that activated aluminum can be prospective energy carrier for small-scale hydrogen power energetics.

Patterning of conducting polymers (CPs) into fully functioning devices remains a challenge for the creation of polymeric bioelectronics. Presently, the most successful method for patterning CPs is preprocess blending with structural components and using either subtractive or additive processes to produce the desired design. This work focuses on the development and characterization of a filter‐based processing method for direct pattern transfer of the CP poly(3,4‐ethylenedioxythiophene) (PEDOT) to elastomeric substrates. Laser sintering of a pattern into the surface of a filter membrane and the subsequent filtering of PEDOT nanowires onto the surface of the filter enable feature sizes of approximately 400 μm to be resolved without the need for any postprocessing. The resulting films of patterned PEDOT nanowires are found to possess high conductivity as well as improved wet electrochemical properties in comparison to platinum. Using the process developed in this work, thin and flexible arrays of PEDOT nanowire films are produced and used as an EMG device to test muscle contractions.