This study reveals the effect of the catalytic 1D supports (carbon, ceria, alumina and titanate) for ruthenium particles on the low temperature release of hydrogen from ammonia. While the state-of-art literature presents Ru/carbon nanotubes (CNT) as the most active catalyst, we found in this work that ruthenium supported on ceria nanorods (Ru/CeO 2 ) catalyst exhibited activity over 8 times higher than the Ru/CNT counterpart system. This enhanced activity is believed to be related to a strong metal-support interaction on the Ru/CeO 2 catalysts promoting the formation of small (~ 3 nm) Ru particles. Addition of sodium as a promoter leads to the formation of smaller Ru particle sizes in addition to the modification of the electronic environment of Ru, enhancing the ammonia decomposition activity at low temperatures. This effect is particularly noticeable in the Ru-Na/CNT catalysts, facilitated by the high conductivity of the support, allowing distant electronic modification of the Ru active sites. This work provides novel insights in designing catalysts for hydrogen production from ammonia in our effort to enable the long-term energy storage in chemical bonds.

Construction of a molecular system in which the magnetic lattice exhibits long-range order is one of the fundamental goals in materials science. In this study, we demonstrate the artificial construction of a ferrimagnetic lattice by doping electrons into acceptor sites of a neutral donor/acceptor metal-organic framework (D/A-MOF). This doping was achieved by the insertion of Li-ions into the D/A-MOF, which was used as the cathode of a Li-ion battery cell. The neutral D/A-MOF is a layered system composed of a carboxylate-bridged paddlewheel-type diruthenium(II,II) complex as the donor and a TCNQ derivative as the acceptor. The ground state of the neutral form was a magnetically disordered paramagnetic state. Upon discharge of the cell, spontaneous magnetization was induced; the transition temperature was variable. The stability of the magnetically ordered lattice depended on the equilibrium electric potential of the D/A-MOF cathode, which reflected the electron-filling level.

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