Related papers: Microbial iron reduction under oxic conditions: im…
Reducible oxides are widely used catalyst supports that can increase oxidation reaction rates by transferring their lattice oxygen at the metal-support interface. The interfacial oxidation process is typically described in terms of a…
Impacts may have had a significant effect on the atmospheric chemistry of the early Earth. Reduced phases in the impactor (e.g., metallic iron) can reduce the planet's H$_2$O inventory to produce massive atmospheres rich in H$_2$. Whilst…
Employing electrons for direct control of nanoscale reaction is highly desirable since it provides fabrication of nanostructures with different properties at atomic resolution and with flexibility of dimension and location. Here, applying…
Whether extant life exists in the martian subsurface is an open question. High concentrations of photochemically produced CO and H2 in the otherwise oxidizing martian atmosphere represent untapped sources of biologically useful free energy.…
Some microbes appear to be able to metabolize in glacial ice or permafrost. The rate depends on temperature, nutrient level, and bioelement availability, among other factors. I have developed a plausible argument that they do this while…
The Cassini mission to the Saturn system discovered a plume of ice grains and water vapor erupting from cracks on the icy surface of the satellite Enceladus. This moon has a global ocean in contact with a rocky core beneath its icy…
The adaptability of extremophiles on Earth raises the question of what strategies putative life might have used to adapt to the present conditions on Mars. Here, we hypothesize that organisms might utilize a water-hydrogen peroxide…
Kinetic understanding of hydrogen co-reduction of multinary and multi-phase oxides is of interest for enhancing sustainability of alloy production and transition to a hydrogen-based economy. Benefits include decrease in energy consumption,…
Biotite crystals are phyllosilicate trioctahedral micas with the general chemical formula K(Mg,Fe)3AlSi3O10(OH)2 that form a solid-solution series with iron-poor phlogopite and iron-rich annite endmembers. With a wide band gap energy and a…
A key challenge in origins-of-life studies is estimating the abundances of species relevant to the chemical pathways proposed to have contributed to the emergence of life on early Earth. Dissolved nitrogen oxide anions (NO$_{X}^{-}$), in…
Photosynthetic microbes have evolved and successfully adapted to the ever-changing environmental conditions in complex microhabitats throughout almost all ecosystems on Earth. In the absence of light, they can sustain their biological…
Metabolism displays striking and robust regularities in the forms of modularity and hierarchy, whose composition may be compactly described. This renders metabolic architecture comprehensible as a system, and suggests the order in which…
Competing geophysical/geochemical hypotheses for how Earth's surface became oxygenated - organic carbon burial, hydrogen escape to space, and changes in the redox state of volcanic gases - are examined and a more biologically-based…
Iron is essential for all known life due to its redox properties, however these same properties can also lead to its toxicity in overload through the production of reactive oxygen species. Robust systemic and cellular control are required…
Mars today has no active volcanism and its atmosphere is oxidizing, dominated by the photochemistry of CO2 and H2O. Using a one-dimensional photochemical model, we consider whether plausible volcanic gas fluxes could have switched the…
The (111) facet of magnetite (Fe$_3$O$_4$) has been studied extensively by experimental and theoretical methods, but controversy remains regarding the structure of its low-energy surface terminations. Using density functional theory (DFT)…
We report superconductivity induced in films of the non-superconducting, antiferromagnetic parent material FeTe by low temperature oxygen incorporation in a reversible manner. X-ray absorption shows that oxygen doping changes the nominal Fe…
Oxygen is a well-studied biosignature. Studying potential abiotic pathways for O2 build-up in exoplanet atmospheres is essential for evaluating whether the detection of O2 would constitute a biosignature detection on other worlds. Previous…
Ferropericlase, (Mg,Fe)O, is the second-most abundant mineral of the Earth's lower mantle. With increasing pressure, the Fe ions in the material begin to collapse from a magnetic to non-magnetic spin state. We present a finite-temperature…
Natural oxidation is a common degradation mechanism of both mechanical and electronic properties for most of the new two-dimensional materials. From another perspective, controlled oxidation is an option to tune material properties,…