Ionic conductivity and disorder in calcium and barium nitrogen hydrogen phases.

Nitrogen-hydrogen based alkali and alkaline earth metal compounds have recently received a substantial amount of attention as co-catalysts for heterogeneous mild condition ammonia synthesis (MCAS). The incorporation of these materials has been shown to result in positive reaction orders with respect to H, solving the issue of hydrogen poisoning, , the occupation of the majority of transition metal (TM) active sites by H-adatoms due to the significantly faster kinetics of H dissociation as compared to N. The mechanism that underlies this is thought to be the incorporation (sinking) of H-adatoms from the surface of TMs to the bulk of the N-H phases.

Hydrogen ionic conductors and ammonia conversions.

Electrochemical and catalytic conversion to and from ammonia is strongly enhanced by appropriate choice of hydrogen conducting electrolyte or substrate. Here we explore both protonic and hydride ionic conductors in relation to ammonia conversions. Protonic conductors tend to require too high a temperature to achieve sufficient hydrogen flux for ammonia synthesis as thermal decomposition competes strongly.

Ion selective permeation through cellulose acetate membranes in forward osmosis.

Solute-solute interactions can have a dramatic impact on the permeation of solutes through dense polymeric membranes. In particular, understanding how solute-solute interactions can affect the design of osmotically driven membrane processes (ODMPs) is critical to the successful development of these emerging water treatment and energy generation processes. In this work, we investigate the influence that solute-solute interactions have on nitrate permeation through an asymmetric cellulose acetate forward osmosis membrane.