Highly active and stable electrocatalysts for hydrogen evolution have been developed on the basis of molybdenum compounds (Mo2C, Mo2N, and MoS2) on carbon nanotube (CNT)-graphene hybrid support via a modified urea-glass route. By a simple modification of synthetic variables, the final phases are easily controlled from carbide, nitride to sulfide with homogeneous dispersion of nanocrystals on the CNT-graphene support. Among the prepared catalysts, Mo2C/CNT-graphene shows the highest activity for hydrogen evolution reaction with a small onset overpotential of 62 mV and Tafel slope of 58 mV/dec as well as an excellent stability in acid media. Such enhanced catalytic activity may originate from its low hydrogen binding energy and high conductivity. Moreover, the CNT-graphene hybrid support plays crucial roles to enhance the activity of molybdenum compounds by alleviating aggregation of the nanocrystals, providing a large area to contact with electrolyte, and facilitating the electron transfer.

Pure formic acid was produced via CO2 hydrogenation over a heterogeneous PdNi alloy catalyst on carbon nanotube-graphene support in water solvent without a base additive.

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Highly ordered, honeycomb-like iron oxide (hematite) films were fabricated by double-step anodic oxidation of iron foil. The honeycomb structure obtained by double step anodization was found to be more effective in producing a large area film with homogeneous pore distribution compared to nanotubes fabricated by the conventional single-step anodic oxidation process. To prevent agglomeration of the hematite film during the annealing process, a thin alumina layer was deposited on the hematite film surface by atomic layer deposition. With this alumina shielding and subsequent removal by alkaline treatment, one-dimensional (1-D) hematite nanostructure was preserved perfectly after annealing at 550 C. This highly ordered 1-D nanostructure film showed much enhanced photoelectrochemical cell performances relative to hematite films with low degrees of ordering.

Generation of hydrogen from renewable sources and its safe utilization for efficient one-pot upgrading of renewable biofuels are a challenge. Bimetallic PdAg catalyst supported on Fe 3 O 4 /nitrogen-doped reduced graphene oxide (N-rGO) were synthesized for hydrogen generation from formic acid with high TOF (497 h −1 at 50 °C), and the hydrogen was subsequently utilized in situ for selective defunctionalization of lignin-derived chemicals with preserved aromatic nature at ambient pressure. Hydrodeoxygenation of aromatic aldehydes and ketones gave excellent yields (99% at 130 °C) with no use of additives. Furthermore, hydrogenolysis of β-O-4 and α-O-4 C−O model compounds produced only two products with high selectivity at 120 °C, which is an efficient and versatile one-pot platform for valorization of lignin biomass.