This talk will discuss some of the limitations and optimizations relating to solar fuels device. From an experimental standpoint, our work on ultra-low Pt loadings for photocatalytic hydrogen production on silicon photocathodes shows that platinum is potentially even more scalable than non-noble metal catalysts. From a modeling standpoint, our web based model at solarfuelsmodeling.com¹ allows users to model and analyze efficiencies of device given various input parameters.  By comparing experimental data to theoretically optimal data, we have quantitatively analyzed how close best in class photoabsorber materials are to reaching their thermodynamic limits.  This approach also shows what the fundamental issues (photocurrent vs. photovoltage) are holding back a particular material.  We have also branched out using this modeling for non-water splitting reactions, such as CO₂ reduction and halide production and the potential for these reactions will also be discussed.

1. A Flexible Web-Based Approach to Modeling Tandem Photocatalytic Devices. Seger B.; Hansen, O.; Vesborg  P.C.K. Solar RRL 2017, 1, 1600013