New metal-free porous framework materials may have potential for hydrogen storage

Phys.org  May 22, 2024 The isoreticular principle, which allows families of structurally analogous frameworks to be built in a predictable strategies do not translate to other common crystalline solids, such as organic salts, in which the intermolecular ionic bonding is less directional. Researchers in the UK showed that chemical knowledge could be combined with computational crystal-structure prediction (CSP) to design porous organic ammonium halide salts that contain no metals. The nodes in the salt frameworks were tightly packed ionic clusters that directed the materials to crystallize in specific ways on the predicted lattice energy landscapes. The energy landscapes allowed them […]

Researchers harness the sun to produce hydrogen gas from water

Phys.org  March 26, 2024 To understand the factors that promote bimetallic H–H coupling researchers at the University of North Carolina at Chapel Hill, USA, subjected molecular iridium catalysts to undergo photoelectrochemical dihydrogen (H2) evolution via a bimolecular mechanism. Covalently tethered diiridium catalysts evolved H2 from neutral water faster than monometallic catalysts, even at lower overpotential. The unexpected origin of this improvement was non-covalent supramolecular self-assembly into nanoscale aggregates that efficiently harvested light and form H–H bonds. Monometallic catalysts containing long-chain alkane substituents leveraged the self-assembly to evolve H2 from neutral water at low overpotential and with rates close to the […]

New catalyst could provide liquid hydrogen fuel of the future

Science Daily   October 12, 2023 Hydrogen for energy storage and hydrogen-powered fuel cells for energy conversion can play important roles. However, storage of hydrogen itself is difficult. Researchers in Sweden investigated a car fuel comprised of a liquid that is converted to hydrogen by a solid catalyst. The used liquid is then emptied from the tank and charged with hydrogen, after which it can be used again. A key part in the adaption of liquid organic hydrogen carriers (LOHCs) is the catalyst design for efficient dehydrogenation of these hydrogen-carrying species. They investigated the use of silica- and alumina-supported POCOP–Ir systems […]