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Formic acid (FA) has been extensively studied as one of the most promising hydrogen energy carriers today. The catalytic decarboxylation of FA ideally leads to the formation of CO2 and H2 that can be applied in fuel cells. A large number of transition‐metal based homogeneous catalysts with high activity and selectivity have been reported for the selective FA dehydrogentaion. In this review, we discussed the recent development of C,N/N,N‐ligand and pincer ligand‐based homogeneous catalysts for the FA dehydrogenation reaction. Some representative catalysts are further evaluated by the CON/COF assessment (catalyst on‐cost number)/(catalyst on‐cost frequency). Conclusive remarks are provided with future challenges and opportunities. [ABSTRACT FROM AUTHOR]

Abstract: For several decades, transition‐metal catalysis has been a popular method for many functional group transformations in organic chemistry. Recent developments in sustainability and applications of earth‐abundant metals have resulted in a synthetic renaissance and have attracted considerable interest in less toxic and inexpensive first‐row transition‐metal catalysts such as nickel. Herein, we highlight some recent computational insights into the reaction mechanisms of Ni‐catalyzed hydrofunctionalizations (i.e., hydrogenation, hydrovinylation, hydroacylation, hydroheteroarylation, hydrosilylation, and hydroalkoxylation) and Ni‐dependent enzymes (i.e., lactate racemase, methyl‐CoM reductase, and [NiFe]‐hydrogenase). These computational studies provide insights into these reaction mechanisms and thus assist in the development and design of sustainable catalysts. [ABSTRACT FROM AUTHOR]

Keywords: formic acid; hydrogen energy carrier; homogeneous catalysis EN formic acid hydrogen energy carrier homogeneous catalysis 933 933 1 04/08/20 20200401 NES 200401 B Fueling the future b : Formic acid (FA) has been extensively studied as one of the most promising hydrogen energy carriers. In this Minireview, the recent development of C,N/N,N-ligand and pincer ligand-based homogeneous catalysts for the FA dehydrogenation reaction were discussed and further evaluated by the CON/COF assessment (catalyst on-cost number)/(catalyst on-cost frequency). Formic acid, hydrogen energy carrier, homogeneous catalysis. [Extracted from the article]

To improve hydrogen storage capacity, MgH2 whiskers are produced directly from common Mg particles through hydrogenation at 420 °C under 2 MPa of H2 for 72 h. The morphology, thermal stability, growth direction, and growth mechanism of the whiskers are investigated. Results show that the as‐prepared sample with whiskers has a hydrogen storage capacity of 7.14 wt.%, but features high thermal stability. Under SEM, the MgH2 whiskers are 400–1000 nm in diameter and their lengths can reach to 150 µm. The long whiskers display, to some extent, flexibility like human hair. XRD test reveals that the preferred orientation for the whisker growth is along the [101] direction of β‐MgH2. Existence of liquid phase MgH2 is demonstrated. Two growth pathways for the MgH2 whiskers have been found according to their different morphologies. One is by vapor–liquid–solid mechanism from hydriding chemical vapor deposition and the other is by stress inducible recrystallization orientated growth from bulk MgH2 particles. Besides, the addition of transition metal (Cu, Co) is found to suppress the growth of MgH2 whiskers. MgH2 whiskers are produced directly from common Mg particles through long‐time hydrogenation. Two growth mechanisms are used to reveal the growth of the MgH2 whiskers. The first one is vapor‐liquid‐solid mechanism from hydriding chemical vapor deposition, in which the liquid phase is proved to be molten MgH2, and the second one is stress inducible recrystallization orientated growth from bulk MgH2 particles. [ABSTRACT FROM AUTHOR]

A variety of target compounds is available by the title process under conditions A). [ABSTRACT FROM AUTHOR]