A facile one-step printing process by 3D micro-extrusion affording binder-free thermally reduced graphene oxide (TRGO) based electrochemical capacitors (ECs) that display high-rate performance is presented. Key intermediates are binder-free TRGO dispersion printing inks with concentrations up to 15 g L −1 . This versatile printing technique enables easy fabrication of EC electrodes, useful in both aqueous and non-aqueous electrolyte systems. The as-prepared TRGO material with high specifi c surface area (SSA) of 593 m 2 g −1 and good electrical conductivity of ≈16 S cm −1 exhibits impressive charge storage performances. At 100 and 120 Hz, ECs fabricated with TRGO show time constants of 2.5 ms and 2.3 ms respectively. Very high capacitance values are derived at both frequencies ranging from 3.55 mF cm −2 to 1.76 mF cm −2 . Additionally, these TRGO electrodes can be charged and discharged at very high voltage scan rates up to 15 V s −1 yielding 4 F cm −3 with 50% capacitance retention. Electrochemical performance of TRGO electrodes in electrolyte containing tetraethyl ammonium tetrafl uoroborate and acetonitrile (TEABF4-ACN) yields high energy density of 4.43 mWh cm −3 and power density up to 42.74 kW cm −3 , which is very promising for AC line fi ltering application and could potentially substitute state of the art electrolytic capacitor technology.

Cobalt (Co) has been considered as one of the candidates for the barrier material in copper (Cu) interconnects. As a metal that is less noble than copper, Co poses two challenges to the integration scheme. For example, during the post-chemical mechanical planarization (CMP) cleaning step, corrosion of Co and galvanic corrosion between Co and Cu may occur. To minimize such corrosion, a corrosion inhibitor is often added into the post-CMP cleaning solution. The present study investigates the interaction between these metals and a representative corrosion inhibitor 1,2,4-triazole (TAZ). More specifically, this study uses various analytical techniques to elucidate the mechanism with which TAZ reduces the corrosion density of Co and Cu and prevents galvanic corrosion between the two metals. Furthermore, it is found that TAZ preferentially forms a passivating film on the relative stable Co surface containing cobalt hydroxide (Co(OH) 2 ) whereas the instability of Co reduces the effectiveness of TAZ inhibition. The corrosion protection for cobalt at pH 10 in presence of TAZ is mainly attributed to the physisorption and chemisorption of TAZ molecules on oxide covered Co surface, which follows Langmuir adsorption isotherm. It is anticipated that the same passivation mechanism may also be applicable to other structurally similar corrosion inhibitors.

High-quality graphene oxide (GO) with high crystallinity and electrical conductivity as well as in situ doped with nitrogen and sulfur is obtained via the electrochemical exfoliation of graphite. Furthermore, iron incorporated GO sheets show promising catalytic activity and stable methanol tolerance durability when used as electrocatalysts for the oxygen reduction reaction.

We report a novel three-dimensional nitrogen containing carbon foam/silicon (CFS) composite as potential material for lithium ion battery anodes. Carbon foams were prepared by direct carbonization of low cost, commercially available melamine formaldehyde (MF, Basotect) foam precursors. The carbon foams thus obtained display a three-dimensional interconnected macroporous network structure with good electrical conductivity (0.07 S/cm). Binder free CFS composites used for electrodes were prepared by immersing the as-fabricated carbon foam into silicon nanoparticles dispersed in ethanol followed by solvent evaporation and secondary pyrolysis. In order to substantiate this new approach, preliminary electrochemical testing has been done. The first results on CFS electrodes demonstrated initial capacity of 1668 mAh/g with 75% capacity retention after 30 cycles of subsequent charging and discharging. In order to further enhance the electrochemical performance, silicon nanoparticles were additionally coated with a nitrogen containing carbon layer derived from codeposited poly(acrylonitrile). These carbon coated CFS electrodes demonstrated even higher performance with an initial capacity of 2100 mAh/g with 92% capacity retention after 30 cycles of subsequent charging and discharging.