Impact of Light-Induced Degradation on the Performance of Multijunction Thin-Film Silicon-Based Photoelectrochemical Water-Splitting Devices

The impact of light-induced degradation (LID) of silicon photoelectrodes on the solar-to-hydrogen efficiency of photoelectrochemical (PEC) devices is investigated. To evaluate the effect, stabilized state-of-the-art thin-film silicon solar cells (after 1000 h of light soaking) were used as photocathodes in photovoltaic-electrochemical (PV-EC) device assemblies and their performances were compared to the performances of the initial solar-cell-based PV-EC devices. A wide range of photoelectrode configurations (tandem, triple, quadruple) was addressed. With regard to the widespread use of multijunction-based photoelectrodes in the literature, the results presented herein will have a high impact and may serve as guidelines for the design of photovoltaic devices particularly tailored for PEC applications, with high stabilities and efficiencies. It is shown that LID affects the performances of PV and PV-EC devices in different ways and strongly depends on the photovoltage of the applied solar cell.