Synthesis and Characterization of Carbon-Based Heterogeneous Catalysts for Energy Release of Molecular Solar Thermal Energy Storage Materials.

Molecular solar thermal energy storage (MOST) systems are rapidly becoming a feasible alternative to energy storage and net-zero carbon emission heating. MOST systems involve a single photoisomerization pair that incorporates light absorption, storage, and heat release processes in one recurring cycle. Despite significant recent advancements in the field, the catalytic back-reaction from MOST systems remains relatively unexplored.

Unravelling the water adsorption in a robust iron carboxylate metal-organic framework.

A Fe-MOF was obtained from aqueous solution in high yield under reflux. The water sorption properties were studied by powder X-ray diffraction, volumetric and gravimetric sorption experiments and molecular simulations. The subsequent filling of hydrophobic and hydrophilic pores as well as the stability of the material are demonstrated.

A metal-organic framework for efficient water-based ultra-low-temperature-driven cooling.

Efficient use of energy for cooling applications is a very important and challenging field in science. Ultra-low temperature actuated (T < 80 °C) adsorption-driven chillers (ADCs) with water as the cooling agent are one environmentally benign option. The nanoscale metal-organic framework [Al(OH)(CHOS)] denoted CAU-23 was discovered that possess favorable properties, including water adsorption capacity of 0.

Development and application of an exchange model for anisotropic water diffusion in the microporous MOF aluminum fumarate.

Diffusion of water in aluminum fumarate was studied by means of pulsed field gradient (PFG) nuclear magnetic resonance (NMR). Due to water molecules exchanging between the intracrystalline anisotropic pore space and the isotropic intercrystalline void space the model of intracrystalline anisotropic diffusion fails to describe the experimental PFG NMR data at high observation times. Therefore, the two-site exchange model developed by Kärger is extended to the case of exchange between an anisotropic and an isotropic site.

Scalable Green Synthesis and Full-Scale Test of the Metal-Organic Framework CAU-10-H for Use in Adsorption-Driven Chillers.

The demand for cooling devices has increased during the last years and this trend will continue. Adsorption-driven chillers (ADCs) using water as the working fluid and low temperature waste energy for regeneration are an environmentally friendly alternative to currently employed cooling devices and can concurrently help to dramatically decrease energy consumption. Due to the ideal water sorption behavior and proven lifetime stability of [Al(OH)(m-BDC)] ∙ x H O (m-BDC = 1,3-benzenedicarboxylate), also denoted CAU-10-H, a green very robust synthesis process under reflux, with high yields up to 95% is developed and scaled up to 12 kg-scale.

Ambient pressure synthesis of MIL-100(Fe) MOF from homogeneous solution using a redox pathway.

Micro- to mesoporous iron(iii) trimesate MIL-100(Fe) is a MOF of high interest for numerous applications. With regard to large-scale synthesis, e.g.

High-yield, fluoride-free and large-scale synthesis of MIL-101(Cr).

MIL-101(Cr), one of the most important prototypical MOFs, is well investigated and widely used in many scientific fields. With regard to MOF synthesis in general, the addition of a modifier is commonly used to improve the properties of the products. The effect of inorganic (mineral) and organic acid modifiers was thoroughly investigated in the synthesis of MIL-101(Cr) and HNO3 could increase the yield to over 80% of a product with average SBET > 3200 m(2) g(-1) in repeated experiments (from an average of 50% in most published syntheses) in small-scale laboratory synthesis.

Multicycle water vapour stability of microporous breathing MOF aluminium isophthalate CAU-10-H.

The hydrothermal stability of aluminium hydroxide isophthalate MOF CAU-10-H was proven, under humid multi-cycling conditions. Detailed in situ thermogravimetric measurements and in situ powder X-ray diffraction analysis during water ad-/desorption were used. A reversible structural change during adsorption was detected and thereby exemplified the robustness of breathing-like MOFs over 700 water vapour ad/desorption cycles.

Porous coordination polymers as novel sorption materials for heat transformation processes.

Porous coordination polymers (PCPs)/metal-organic frameworks (MOFs) are inorganic-organic hybrid materials with a permanent three-dimensional porous metal-ligand network. PCPs or MOFs are inorganic-organic analogs of zeolites in terms of porosity and reversible guest exchange properties. Microporous water-stable PCPs with high water uptake capacity are gaining attention for low temperature heat transformation applications in thermally driven adsorption chillers (TDCs) or adsorption heat pumps (AHPs).

Programming MOFs for water sorption: amino-functionalized MIL-125 and UiO-66 for heat transformation and heat storage applications.

Sorption-based heat transformation and storage appliances are very promising for utilizing solar heat and waste heat in cooling or heating applications. The economic and ecological efficiency of sorption-based heat transformation depends on the availability of suitable hydrophilic and hydrothermally stable sorption materials. We investigated the feasibility of using the metal-organic frameworks UiO-66(Zr), UiO-67(Zr), H2N-UiO-66(Zr) and H2N-MIL-125(Ti) as sorption materials in heat transformations by means of volumetric water adsorption measurements, determination of the heat of adsorption and a 40-cycle ad/desorption stress test.

High performance metal-organic-framework coatings obtained via thermal gradient synthesis.

For many possible applications of metal-organic frameworks, a coating onto a metallic support capable of both superior heat and mass transfer is required. A heated substrate in contact with a chilled solution of metal salt and linker reproducibly yields polycrystalline, highly stable, thermally conductive MOF coatings at a growth rate of 50 μm h(-1), illustrated by the formation of Cu(3)(btc)(2) as an example.

MOFs as adsorbents for low temperature heating and cooling applications.

The 3D metal-organic framework (MOF) (3)(infinity){[Ni(3)(mu(3)-btc)(2)(mu(4)-btre)(2)(mu-H(2)O)(2)]. approximately 22H(2)O} is found to be a reversibly dehydratable-hydratable water-stable MOF material with a large loading spread of 210 g/kg as a candidate for solid adsorbents in heat transformation cycles for refrigeration, heat pumping, and heat storage.