Phys.org August 7, 2023 Recently it was predicted based on ab initio quantum Monte Carlo simulations that, in a uniform electron gas, the peak ω0 of the dynamic structure factor S(q,ω) exhibits an unusual nonmonotonic wave number dependence, where dω0/dq<0, at intermediate q, under strong coupling conditions. Researchers in Germany predicted that this nonmonotonic dispersion resembling the roton-type behavior known from superfluids should be observable in a dense, partially ionized hydrogen plasma. Based on a combination of path integral Monte Carlo simulations and linear response results for the density response function, they presented the approximate range of densities, temperatures and […]
Tag Archives: Hydrogen
Seawater split to produce ‘green’ hydrogen
Science Daily February 1, 2023 The use of vast amounts of high-purity water for hydrogen production may aggravate the shortage of freshwater resources. Seawater is abundant but must be desalinated before use in typical proton exchange membrane (PEM) electrolysers. An international team of researchers (China, Australia, USA – Kent State University) has demonstrated direct electrolysis of real seawater that has not been alkalised nor acidified, achieving long-term stability exceeding 100 h at 500 mA cm−2 and similar performance to a typical PEM electrolyser operating in high-purity water. This was done by introducing a Lewis acid layer (for example, Cr2O3) on transition metal oxide catalysts […]
Revolutionary technique to generate hydrogen more efficiently from water
Phys.org October 27, 2022 Typically, electron transfer proceeds solely through either a metal redox chemistry or an oxygen redox chemistry without the concurrent occurrence of both metal and oxygen redox chemistries in the same electron transfer pathway. An international team of researchers (Singapore, USA – Brookhaven National Laboratory, China) has discovered an electron transfer mechanism that involves a switchable metal and oxygen redox chemistry in nickel-oxyhydroxide-based materials with light as the trigger. The proposed light-triggered coupled oxygen evolution mechanism requires the unit cell to undergo reversible geometric conversion between octahedron (NiO6) and square planar (NiO4) to achieve electronic states with […]