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A series of zinc-based catalysts was evaluated for their efficiency in decomposing formic acid into molecular hydrogen and carbon dioxide in the gas phase using quadrupole ion trap mass spectrometry experiments. The effectiveness of the catalysts in the series [(L)Zn(H)]+ , where L=2,2':6',2''-terpyridine (tpy), 1,10-phenanthroline (phen) or 2,2'-bipyrydine (bpy), was found to depend on the ligand used, which turned out to be fundamental in tuning the catalytic properties of the zinc complex. Specifically, [(tpy)Zn(H)]+ displayed the fastest reaction with formic acid proceeding by dehydrogenation to produce the zinc formate complex [(tpy)Zn(O2 CH)]+ and H2 . The catalysts [(L)Zn(H)]+ are reformed by decarboxylating the zinc formate complexes [(L)Zn(O2 CH)]+ by collision-induced dissociation, which is the only reaction channel for each of the ligands used. The decarboxylation reaction was found to be reversible, since the zinc hydride complexes [(L)Zn(H)]+ react with carbon dioxide yielding the zinc formate complex. This reaction was again substantially faster for L=tpy than L=phen or bpy. The energetics and mechanisms of these processes were modelled using several levels of density functional theory (DFT) calculations. Experimental results are fully supported by the computational predictions.

A new decarbonylation reaction is observed for [(K2-acetate)Pd(K2-diphosphine)]+ complexes. Gas-phase IR experiments identify the product as [CH3Pd(OP(Ph2)CH2PPh2)]+. DFT calculations uncovered a plausible mechanism involving O atom abstraction by the diphosphine ligand within the coordination sphere to yield the acetyl complex, [CH3COPd(OP(Ph2)CH2PPh2)]+, which then undergoes decarbonylation.

Two pseudohalide thiocyanate ions (SCN � ) have been used to replace two iodides in CH3NH3PbI3, and the resulting perovskite material was used as the active material in solar cells. In accelerated stability tests, the CH3NH3Pb(SCN)2I perovskite films were shown to be superior to the conventional CH3NH3PbI3 films as no significant degradation was observed after the film had been exposed to air with a relative humidity of 95 % for over four hours, whereas CH3NH3PbI3 films degraded in less than 1.5 hours. Solar cells based on CH3NH3Pb(SCN)2I thin films exhibited an efficiency of 8.3 %, which is comparable to that of CH3NH3PbI3 based cells fabricated in the same way. Perovskite-type CH3NH3PbX3 solid-state solar cells with over 19 % efficiency have recently been reported. (1) They represent promising candidates for next-generation photo- voltaic devices owing to their astoundingly high efficiency, the low costs associated with their solution-based fabrication, and tunable optical properties. (2) Furthermore, this material performs very well in terms of both charge transport (electron/hole diffusion lengths of ca. 1 mm and 1.2 um, respectively, for CH3NH3PbI3� xClx), (3) and light absorption (1.5 � 10 4 cm � 1 at 550 nm). (4) In general, perovskite solar cells