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Water electrolysis using renewable energy inputs is being actively pursued as a green route for hydrogen production. However, it is limited by the high energy consumption due to the sluggish...

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The electrochemical oxidation of furfural and down-pathway intermediate and product species (furoic acid, 2­(5H)-furanone, 5-hydroxy-2­(5H)-furanone, and maleic acid) is investigated on platinum electrodes via attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) with modulation excitation spectroscopy (MES). Density functional theory (DFT) calculations are performed to further illuminate the elementary reaction mechanism and the surface orientations of key reaction intermediates. Evidence from these techniques suggests that oxidation selectivity of the furanic compounds is governed by a balance between several properties of the catalyst. Propensity toward C–C cleavage steps yields self-limiting accumulation of adsorbed CO at low potentials and promotes the formation of C4 products and CO2 at higher potentials. Affinity for surface carboxylates such as furoate and maleate species also leads to their accumulation on the surface at higher potentials. It is thus suggested that correlations between the various surface oxygenate binding energies represent a challenge in balancing accumulation of strongly bound intermediates against a need for the surface to bind hydroxyl to initiate O-addition steps.

Nanoemulsion synthesis has proven to be an effective way for transportation of immobile, insoluble bioactive compounds. Citronella Oil (lemongrass oil), a natural plant extract, can be used as a mosquito repellent and has less harmful effects compared to its available market counterpart DEET (N, N-Diethyl-meta-toluamide). Nanoemulsion of citronella oil in water was prepared using cavitation-assisted techniques while investigating the effect of system parameters like HLB (Hydrophilic Lipophilic Balance), surfactant concentration, input energy density and mode of power input on emulsion quality. The present work also examines the effect of emulsification on release rate to understand the relationship between droplet size and the release rate. Minimum droplet size (60nm) of the emulsion was obtained at HLB of 14, S/O ratio of 1.0, ultrasound amplitude of 50% and irradiation time of 5min. This study revealed that hydrodynamic cavitation-assisted emulsification is more energy efficient compared to ultrasonic emulsification. It was also found that the release rate of nanoemulsion enhanced as the droplet size of emulsion reduced.

is key to the development of processes that can convert CO and CO 2 to hydrocarbons, and nitrate to ammonia. The hydrogen evolution reaction (HER) often competes with these processes. Few studies studied this reaction on Cu under alkaline conditions. Herein, we examined the HER on Cu electrodes under alkaline conditions in Na + -and Cs + -containing electrolytes. We found that in 0.1 M solutions of NaOH and CsOH of the highest commercially available purity grades, trace impurities of iron deposit on the Cu electrode during electrolysis. As a result, the rate of the HER is enhanced by up to a factor of ≈5 over the course of eleven cyclic voltammograms (CV) from 0.15 to −0.65 V vs the reversible hydrogen electrode. After removal of the iron impurities, the CVs are stable as a function of cycle number. Comparison of the CVs in pre-electrolyzed 0.1 M NaOH and CsOH reveals that changing the cation from Na + to Cs + has no measurable effect on the HER. With density functional theory (DFT), we further rationalized our experimental findings. We discuss the implications of our results for electrocatalytic processes on Cu electrodes.

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