808142-88-3Relevant academic research and scientific papers
Homogeneous catalytic system for photoinduced hydrogen production utilizing iridium and rhodium complexes
Cline, Eric D.,Adamson, Samantha E.,Bernhard, Stefan
, p. 10378 - 10388 (2009/04/14)
An efficient homogeneous catalytic system for the visible-light-induced production of hydrogen from water utilizing cyclometalated iridium(III) and tris-2,2′-bipyridyl rhodium(III) complexes is described. Synthetic modification of the photosensitizer lr(C∧N)2(N∧N)+ and water reduction catalyst Rh(N∧N)33+ creates a family of catalysts with diverse photophysical and electrochemical properties. Parallel screening of the various catalyst combinations and photoreaction conditions allows the rapid development of an optimized photocatalytic system that achieves over 5000 turnovers with quantum yields (1/2 H2 per photon absorbed) greater than 34%. Photophysical and electrochemical characterization of the optimized system reveals that the reductive quenching pathway provides the necessary driving force for the formation of [Rh(N∧N)2]0, the active catalytic species for the reduction of water to produce hydrogen. Tests for system poisoning with mercury or CS2 provide strong evidence that the system is a true homogeneous system for photocatalytic hydrogen production.
Accelerated luminophore discovery through combinatorial synthesis
Lowry, Michael S.,Hudson, William R.,Pascal Jr., Robert A.,Bernhard, Stefan
, p. 14129 - 14135 (2007/10/03)
A method for accelerating the discovery of ionic luminophores using combinatorial techniques is reported. The photophysical properties of the resulting transition-metal-based chromophores were compared against a series of analogous, traditionally prepared species. The strong overlap between these two sets confirms the identity of the parallel synthesis products and supports the truthfulness of the combinatorial results. Further support for the combinatorial method comes from the adherence of these complexes to the energy gap law. The relationship between the structure of a complex and its photophysical properties was also considered, and static DFT calculations were used to assess whether it is feasible to predict the luminescent behavior of novel materials.
