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The Shockley-Queisser formulation is a guideline for solar cell technology. However, the SQ limit is fragile with respect to underlying parameters such as material quality and optical design. These are the aspects that should be optimized to approach this limit.   Defect such as **grain boundaries** can alter electronic properties \cite{Yan_2011} in a uncontrolled fashion. Pushing cell conversion efficiencies beyond 20% will require increasing VOC beyond 1V. However the present pathway of processing optimization will likely yield VOC and efficiency converging on 0.9 V and <20%, respectively.\cite{McCandless_2013}. respectively. \cite{McCandless_2013}.  Therefore engineer the photon dynamics and internal fluorescence of a PV cell is essential in reaching theoretical efficency.