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Hydrogen released from chemical hydride ammonia borane (AB, NH3BH3) can be greatly improved when AB is confined in metal–organic frameworks (MOFs), showing reduced decomposition temperature and suppressed unwanted byproducts. However, it is still debatable whether the mechanism of improved AB dehydrogenation is due to catalysis or nanosize. In this research, selected MOFs (IRMOF-1, IRMOF-10, UiO-66, UiO-67, and MIL-53­(Al)) were chosen to explore both catalytic effect of the metal clusters and the manipulation of pore size for nanoconfinement by variations in ligand length. When AB particle size was restricted by the controlled micropores of MOFs, we observed that the decomposition temperature was not correlated to the MOF catalytic environment, but inversely proportional to the reciprocal of the particle size. The results correspond well with the derived thermodynamic model for AB decomposition considering surface tension of nanoparticles.

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A fruitful paradigm in the development of low‐cost and efficient water splitting systems for hydrogen generation is to search the highly active non‐noble catalysts towards hydrogen evolution reaction (HER). Here, the electrocatalytic HER activity of nanostructured amorphous nickel boride (Ni−B) alloy has been investigated. Amorphous Ni−B has exhibited excellent catalytic efficiency and long‐term stability for HER over a broad pH range, which is actually comparable to the performance of Pt. This high catalytic activity is due to the amorphous structure and the moderate electron structure of Ni−B. The Ni−B catalyst is easily obtained via electroless plating technique and we could get a supported Ni−B catalyst on desired substrates. Given the low cost, abundance, corrosion resistance, high efficiency and ease of fabrication, amorphous Ni−B is among the best alternatives to noble metal hydrogen evolution catalysts for water splitting.

Thermodynamic properties of glycerin steam reforming have been studied with the method of Gibbs free energy minimization for hydrogen and/or synthesis gas production. Equilibrium compositions including the coke-formed and coke-free regions were determined as a function of water/glycerin molar ratios (1:1-12:1) and reforming temperatures (550-1200 K) at different pressures (1-50 atm). Optimum conditions for hydrogen production are temperatures between 925 and 975 K and water/glycerin ratios of 9-12 at atmospheric pressure, whereas temperatures above 1035 K and water/glycerin ratios between 2 and 3 at 20-50 atm are suitable for the production of synthesis gas that favors both methanol synthesis and low-temperature Fischer-Tropsch synthesis. However, synthesis gas obtained from glycerin steam reforming is not feasible for direct use in high-temperature Fischer-Tropsch synthesis. Under these optimum conditions, carbon formation can be thermodynamically inhibited.