The conversion of light energy into chemical energy is a focus of much research. Solar energy is of sufficient energy
to drive water splitting to generate hydrogen and oxygen. The splitting of water involves multi-electron reactions and
the breaking and formation of chemical bonds. Light driven water splitting has therefore proven elusive.
Supramolecular complexes that contain ruthenium or osmium polyazine units can efficiently absorb visible light and
generate charge transfer excited states. While many supramolecular complexes can absorb solar light efficiently, few are
able to convert this energy into chemical energy via the conversion of a readily available chemical feedstock into a fuel.
One process that is proposed as applicable for light to energy conversion is photoinitiated electron collection.
Photoinitiated electron collection is a multi-step process whereby light energy is used to collect reducing equivalents.
The collection of reducing equivalents is an essential step in the use of light energy to drive multi-electron reactions such
as water splitting. The development of mixed-metal complexes as photoinitiated electron collectors is described,
including the factors impacting device function. The use of Rh based electron collectors allows for the reducing
equivalents generated by photoinitiated electron collection to be transferred to substrates, such as the reduction of water
to produce hydrogen.
In the investigation of alternative energy sources, specifically, solar hydrogen production from water, the ability to
perform experiments with a consistent and reproducible light source is key to meaningful photochemistry. The design,
construction, and evaluation of a series of LED array photolysis systems for high throughput photochemistry have been
performed. Three array systems of increasing sophistication are evaluated using calorimetric measurements and
potassium tris(oxalato)ferrate(II) chemical actinometry and compared with a traditional 1000 W Xe arc lamp source. The
results are analyzed using descriptive statistics and analysis of variance (ANOVA). The third generation array is
modular, and controllable in design. Furthermore, the third generation array system is shown to be comparable in both
precision and photonic output to a 1000 W Xe arc lamp.