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Meroueh, Laureen

Publications and source records attributed to Meroueh, Laureen.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Next-generation anion exchange membrane water electrolyzers operating for commercially relevant lifetimes

Alkaline anion exchange membrane (AEM) water electrolysis has gained increasing attention due to its potential to achieve low-cost, high performance hydrogen production. However, most existing membranes are not durable in industrial settings. In this work, we demonstrate good performance relative to industrial parameters using Sustainion® anion exchange membranes. Long-duration tests showed stable performance of 1 A/cm 2 at 1.85 V with a degradation rate of less than 1 μV/h over 10,000 h. The projected lifetime is thus over 20 years. Daily on/off cycling performance over the course of 30 years was simulated experimentally through accelerated voltage shock tests, resulting in a performance loss of only 0.15 μV/cycle over 11,000 cycles. As shown through impact and crossover testing, an improvement in performance is achieved by the addition of zirconia to the polymer matrix and mechanically reinforcing the membrane.

08 HYDROGEN↗
DOE OSTI2018

Energy storage based on SrCO 3 and Sorbents—A probabilistic analysis towards realizing solar thermochemical power plants

As greenhouse gases threaten our environment, it has become increasingly necessary to replace consumption of fossil fuels with renewable energy. Without energy storage, solar cannot provide power at night during times of peak demand, resulting in a gap between supply capabilities and demand. Solar thermochemical energy storage (TCES) has potential to resolve this critical temporal issue. An 800MWh th TCES subsystem has been designed to cost-effectively convert solar energy to electricity. An evaluation of each required component is provided, including the reactor chemistry. Strontium carbonate decomposition is used to densely store high temperature thermal energy via chemical reaction, while two different CO 2 storage methods are considered. To determine the practical feasibility of these schemes, a probabilistic analysis has been performed to explore exergy and energy efficiency, and cost. It has been found that a scheme storing CO 2 via sorbents is capable of ~71% energy and ~87% exergy efficiency, and an installed cost of ~48 USD kWh th -1 .

25 ENERGY STORAGE↗
DOE OSTI2017

Tailoring Superconductivity with Quantum Dislocations

Despite the established knowledge that crystal dislocations can affect a material’s superconducting properties, the exact mechanism of the electron-dislocation interaction in a dislocated superconductor has long been missing. Being a type of defect, dislocations are expected to decrease a material’s superconducting transition temperature (T c ) by breaking the coherence. Yet experimentally, even in isotropic type I superconductors, dislocations can either decrease, increase, or have little influence on T c . These experimental findings have yet to be understood. Although the anisotropic pairing in dirty superconductors has explained impurity-induced T c reduction, no quantitative agreement has been reached in the case a dislocation given its complexity. By generalizing the one-dimensional quantized dislocation field to three dimensions, we reveal that there are indeed two distinct types of electron-dislocation interactions. Besides the usual electron-dislocation potential scattering, there is another interaction driving an effective attraction between electrons that is caused by dislons, which are quantized modes of a dislocation. The role of dislocations to superconductivity is thus clarified as the competition between the classical and quantum effects, showing excellent agreement with existing experimental data. In particular, the existence of both classical and quantum effects provides a plausible explanation for the illusive origin of dislocation-induced superconductivity in semiconducting PbS/PbTe superlattice nanostructures. A quantitative criterion has been derived, in which a dislocated superconductor with low elastic moduli and small electron effective mass and in a confined environment is inclined to enhance T c . This provides a new pathway for engineering a material’s superconducting properties by using dislocations as an additional degree of freedom.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗