Department of Chemistry and Materials Science, Aalto University, 00076, Aalto, Finland.
Published: September 2019
AI Article Synopsis
Article Abstract
The combined atomic and molecular layer deposition (ALD/MLD) technique offers a unique way to build-both known and previously unknown-crystalline coordination polymer materials directly from gaseous precursors in a high-quality thin-film form. Here, we demonstrate the ALD/MLD of crystalline Li-, Na-, and K-based 3,5-pyridinedicarboxylate (3,5-PDC) thin films; the Li -3,5-PDC films are of the known Li-ULMOF-4 crystal structure whereas the other as-deposited crystalline films possess structures not previously reported. Another exciting possibility offered by ALD/MLD is the deposition of well-defined but amorphous metal-organic thin films, such as our Mg-, Ca-, Sr-, and Ba-based 3,5-PDC films, which can then be crystallized into water-containing structures through a post-deposition humidity treatment. All together, the new metal-organic structures realized in this study through ALD/MLD comprise a majority of the (anhydrous and water-containing) members of the s-block metal 3,5-pyridinedicarboxylate family.
TUM School of Natural Sciences, Department of Chemistry, Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, Garching bei München 85748, Germany.
The activation of C-F bonds has long been regarded as the subject of research in organometallic chemistry, given their synthetic relevance and the fact that fluorine is the most abundant halogen in the Earth's crust. However, C-F bond activation remains a largely unsolved challenge due to the high bond dissociation energies, which was historically dominated by transition metal complexes. Main group elements that can cleave unactivated monofluorobenzene are still quite rare and restricted to s-block complexes with a biphilic nature.
Terminal oxygen radicals involving p- and d-block atoms are quite common, but s-block compounds with an oxygen radical character remain rare. Here, we report that alkaline-earth metal beryllium atoms react with OF to form the oxygen beryllium fluorides OBeF and OBeF. These species are characterized by matrix-isolation infrared spectroscopy with isotopic substitution and quantum-chemical calculations.
College of Materials Science and Engineering, Pinghu Institute of Advanced Materials, Zhejiang University of Technology, Hangzhou, 310014, P. R. China.
The development of efficient oxygen electrocatalysts is crucial for improving Zn-air batteries (ZABs) across various temperatures.
A new approach using magnesium (Mg) to modulate cobalt (Co) catalysts shows enhanced electrocatalytic performance, with the MgCo─NC catalyst exhibiting an impressive lower activation energy for the oxygen reduction reaction.
The MgCo─NC catalyst not only delivers a high power density of 157.0 mW/cm², but also demonstrates remarkable durability and minimal capacity loss even under extreme temperature variations.
Rubidium and cesium are the least studied naturally occurring s-block metals in organometallic chemistry but are in plentiful supply from a sustainability viewpoint as highlighted in the periodic table of natural elements published by the European Chemical Society. This underdevelopment reflects the phenomenal success of organometallic compounds of lithium, sodium, and potassium, but interest in heavier congeners has started to grow. Here, the synthesis and structures of rubidium and cesium bis(amido)alkyl magnesiates [(AM)MgN'alkyl], where N' is the simple heteroamide N(SiMe)(Dipp), and alkyl is Bu or CHSiMe, are reported.
Context: The s-block metals dissolved in ammonia form metal-ammonia complexes with diffuse electrons which could be used for redox catalysis. In this theoretical paper, we investigated the possibility of the d-bloc transition metals (Mn, Fe, Co, Ni, and Cu) solvated by ammonia. It has been demonstrated that both Mn and Fe atoms undergo into an oxidative reaction with NH forming an inserted species, HMNH.
