n-MoS₂/p-Si Solar Cells with Al₂O₃ Passivation for Enhanced Photogeneration

Molybdenum disulfide (MoS₂) has recently emerged as a promising candidate for fabricating ultrathin-film photovoltaic devices. These devices exhibit excellent photovoltaic performance, superior flexibility, and low production cost. Layered MoS₂ deposited on p-Si establishes a built-in electric field at MoS₂/Si interface that helps in photogenerated carrier separation for photovoltaic operation. We propose an Al₂O₃-based passivation at the MoS₂ surface to improve the photovoltaic performance of bulklike MoS₂/Si solar cells. Interestingly, it was observed that Al₂O₃ passivation enhances the built-in field by reduction of interface trap density at surface. Our device exhibits an improved power conversion efficiency (PCE) of 5.6%, which to our knowledge is the highest efficiency among all bulklike MoS₂-based photovoltaic cells. The demonstrated results hold the promise for integration of bulklike MoS₂ films with Si-based electronics to develop highly efficient photovoltaic cells.