Ni-CeO2 is a highly efficient, stable and non-expensive catalyst for methane dry reforming at relative low temperatures (700 K). The active phase of the catalyst consists of small nanoparticles of nickel dispersed on partially reduced ceria. Experiments of ambient pressure XPS indicate that methane dissociates on Ni/CeO2 at temperatures as low as 300 K, generating CHx and COx species on the surface of the catalyst. Strong metal-support interactions activate Ni for the dissociation of methane. The results of density-functional calculations show a drop in the effective barrier for methane activation from 0.9 eV on Ni(111) to only 0.15 eV on Ni/CeO2-x (111). At 700 K, under methane dry reforming conditions, no signals for adsorbed CHx or C species are detected in the C 1s XPS region. The reforming of methane proceeds in a clean and efficient way.

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The ultra-low density graphene xerogel was prepared through the chemical reduction of graphene oxide suspension using a hypophosphorous acid-iodine mixture. The chemically converted graphene xerogel (CCGX) exhibited superior electrical conductivity (up to 500 S m(-1)) and high C/O atomic ratio (14.7), which were the highest values reported for the graphene-based xerogel.

Chemically converted graphene that was reduced with phenylhydrazine was highly dispersed in organic solvents, and its "paper" prepared by filtration of the reduced graphene possessed an electrical conductivity value as high as 20,950 S m(-1).

The immobilization of miniscule quantities of RuO2 (~ 0.1%) onto one-dimensional (1D) TiO2 nanorods (NRs) allows H2 evolution from water under the irradiation of visible light.Rod-like rutile TiO2 structures, exposing preferentially (110) surfaces, are shown to be critical for the deposition of RuO2 to enable photocatalytic activity in the visible region. This performance is rationalized based on fundamental experimental studies and theoretical calculations, demonstrating that RuO2(110) grown as 1D nanowires on rutile TiO2(110), which occurs only at extremely low loads of RuO2, leads to the formation of a heterointerface that efficiently adsorbs visible light.