At potentials negative of the photocurrent onset, two distinct semicircles are observed in the Nyquist plot and there is currently ambiguity regarding the choice of EC. Each of these semicircles represents a process with an associated resistance and capacitance occurring within the system. Parameters extracted from the high and low frequency semicircles have been labelled as silicon and interface, respectively. The reasons behind these designations will be clarified throughout this report. Two EC options, the Voight and Maxwell circuit, are shown in Figure (b) and (c), respectively. The third option is the nested circuit, however as shown in Figure , the Voight and nested circuits result in indistinguishable fits. Moving forward, the Voight circuit will be used to represent both the Voight and nested ECs and be compared against results using the Maxwell circuit.