Al-N-Compounds – Possible Materials for Hydrogen Storage

Aluminum hydride (AlH3) by itself has already been considered as a hydrogen storage material over 50 years ago based on its high volumetric (148 g H2 L-1) and gravimetric (10.1 wt.-%) hydrogen density. Based on its low decomposition temperature and light weight, research on AlH3 confining the impractical re-hydrogenation conditions is still in progress. Attempts to stabilize AlH3 with a Lewis base, such as an amine, lead to a significant reduction of the thermodynamic hydrogenation barrier of Al. This approach enables the hydrogenation at room temperature and reasonable pressures to generate amine AlH3 adducts, called amino alanes. The influence of tertiary amines leads to stabilized phases under mild conditions offering promising properties for reversible hydrogenation.
[1]   J. Ortmeyer, A. Bodach, L. Sandig-Predzymirska, B. Zibrowius, F. Mertens, M. Felderhoff, Direct Hydrogenation of Aluminum via Stabilization with Triethylenediamine: A Mechanochemical Approach to Synthesize the Triethylenediamine AlH₃ Adduct, ChemPhysChem, 2019, DOI: 10.1002/cphc.20180109
[2]     M.B. Ley, T. Bernert, J. Ruiz-Fuertes, R. Goddard, C. Fares, C. Weidenthaler, M. Felderhoff, The plastic crystalline A15 phase of dimethylaminoalane, [N(CH3)2–AlH2]3, Chem. Commun. 2016, 52, 11649–11652.

By: Dr. Michael FEDERHOFF
MPI Mülheim an der Ruhr - Germany

Dr. Camille Petit

Approaches to porous materials development to address separation challenges

ChE-605 - Highlights in Energy Research seminar series
Access to clean water along with sustainable energy and the protection of the environment are probably the greatest challenges of our society but also a unique opportunity to reshape our technology landscape. Major molecular separation issues underpin these areas. Take for instance CO2 capture: here, one wishes to separate CO2 from other flue gas (or ambient air) components. Notably, existing separation processes account for 10 to 15% of the world energy consumption. Researchers must propose transformative approaches to molecular separations possibly exploiting the increasing complexity and sophistication of materials available to perform such separations.
This seminar will provide an overview of our research – past and current – in that direction. I will discuss selected examples of our work on the design, synthesis, characterisation and testing of porous materials (i.e. sorbents) to address separation challenges related to environmental, water and energy sustainability. I will focus specifically on our study of metal-organic frameworks and porous boron nitride for applications in carbon management and solar energy conversion. I will describe how our approach to material design, which combines aspects of chemistry, materials science and chemical engineering, enables us to identify key materials structure-property relationships while also accelerating the identification of the ‘best’ material for a given application.

By: Dr. Camille PETIT
Department of Chemical Engineering,
Barrer Centre, Imperial College London

Electrochemical CO2 Reduction Across Scales: From Mechanistic Pathways to Practical Applications

ChE-605 - Highlights in Energy Research seminar series
Electrocatalytic CO2 reduction has the dual-promise of neutralizing carbon emissions in the near future, while providing a long-term pathway to create energy-dense chemicals and fuels from atmospheric CO2. The field has advanced immensely in recent years, taking significant strides towards commercial realization. While catalyst innovations have played a pivotal role in increasing the product selectivity and activity of both C1 and C2 products, slowing advancements indicate that electrocatalytic performance may be approaching a hard cap. Meanwhile, innovations at the systems level have resulted in the intensification of CO2 reduction processes to industrially‑relevant current densities by using pressurized electrolytes, gas-diffusion electrodes and membrane-electrode assemblies to provide ample CO2 to the catalyst. The immediate gains in performance metrics offered by operating under excess CO2 conditions goes beyond a reduction of system losses and high current densities, however, with even simple catalysts outperforming many of their H-cell counterparts. This talk will focus on some of the underlying reasons for the observed changes in catalytic activity, and propose that further advances can be made by shifting additional efforts in catalyst discovery and fundamental studies to system-integrated testing platforms.  Recent results will be shown that highlight the use of computational modeling, in-situ/operando spectroelectrochemistry, and reactor engineering to understand and optimize electrochemical systems across many scales.

By: Prof. Wilson A. SMITH
Department of Chemical Engineering,
Delft University of Technology, The Netherlands

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