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Conventional thermocatalytic hydrogenation employs high temperatures and pressures and often exhibits low selectivity toward desired products. Electrochemical hydrogenation can reduce energy input by operating at ambient conditions and improving process control and selectivity; however, electrocatalysts face stability and conductivity limitations. To overcome these obstacles, we physically mixed a traditional electrocatalyst (Pd black) with a hydrogenation‐active metal (Pd) supported on a conventional metal oxide support (alumina, Al2O3) and investigated electrochemical hydrogenation of furfural, a model biomass compound. Experiments were conducted in a proton exchange membrane (PEM) reactor, in which synthesized electrocatalysts were used as cathodes. Catalysts with Pd black and varying loadings of Pd on Al2O3 were used to determine the impact of hydrogen spillover on electrocatalytic hydrogenation mechanisms, selectivity, and rates. Observed hydrogenation rates and selectivities were linked to structural and compositional properties of the catalyst mixtures. Of the Pd black cathodes tested, 5 wt % Pd/Al2O3 exhibited production rates as high as pure Pd black and higher selectivity towards completely hydrogenated products. Improved selectivity and rates were attributed to a synergistic interaction between Pd black and 5 wt % Pd/Al2O3 in which Pd/Al2O3 increased the number of active sites, while Pd black provided stable conductivity.

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Early transition metal carbides and nitrides (ETMCNs), materials in which carbon or nitrogen occupies interstitial sites within a parent metal lattice, possess unique physical and chemical properties that motivate their use as catalysts. Specifically, these materials possess multiple types of catalytic sites, including metallic, acidic, and basic sites, and as such, exhibit reactivities that differ from their parent metals. Moreover, their surfaces are dynamic under reaction conditions. This chapter reviews recent (since 2010) experimental and computational investigations into the catalytic properties ofETMCNmaterials for applications including biomass conversion, syngas andCO2upgrading, petroleum and natural gas refining, and electrocatalytic energy conversion, energy storage, and chemicals production, and attempts to link catalyst performance to active site identity/surface structure in order to elucidate the present level of understanding of structure–function relationships for these materials. The chapter concludes with a perspective on leveraging the unique properties of these materials to design and develop improved catalysts through a dedicated, multidisciplinary effort.

Silver nanoparticles are formed through an environmentally-benign electrochemically-driven method on type 304 stainless steel electrodes, with potential energy and biomedical applications. An electrochemically-deposited initial layer of chitosan strongly adheres to the passive layer formed on the 304 stainless steel electrodes. Electrochemical deposition from a subsequent silver nitrate solution forms nanoparticles in the size range of 10 to 200 nm depending on processing parameters, in situ, rapidly and at room temperature. The overall coating has been shown to possess mechanical cohesiveness, flexibility, and durability, including remarkable stability with atmospheric exposure (both of the matrix and the nanoparticles contained within). Infrared, Raman and UV-vis spectroscopies, synchrotron X-ray absorption, and electron microscopy have been used to characterize the materials and indicate that chitosan provides protection from environmental degradation (as well as promotes formation of the nanoparticles).

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