Fabrication of Centimeter‐Scale MoWS ₂ ‐Based High Performing Solar Cells

ABSTRACT The growing demand for efficient, scalable, and lightweight photovoltaic (PV) technologies has intensified interest in WS ₂ and MoS ₂ ‐based devices. Despite notable advances, achieving simultaneously high performance and long‐term operational stability remains a key barrier to broader adoption. Here, we address this challenge by fabricating p–n heterojunction solar cells through a single‐step chemical vapor deposition process that directly deposits WS ₂ , MoS ₂ , and their alloy MoWS ₂ onto p‐type silicon substrates. The MoWS ₂ alloy exhibits a reduced bandgap and enhanced optoelectronic properties, which translate into substantially improved PV output and device robustness. The MoWS ₂ ‐based solar cell achieves a power conversion efficiency of 5.8%, outperforming the WS ₂ and MoS ₂ counterparts, which reach 1.12% and 3.6%, respectively. In addition, MoWS ₂ displays markedly enhanced light‐harvesting capability, with an external quantum efficiency of 80%, compared to 30% for WS ₂ and 50% for MoS ₂ . Stability assessments further demonstrate that MoWS ₂ retains its performance over a 30‐day test period, confirming its superior long‐term durability. By establishing the viability of MoWS ₂ as a high‐potential photoactive material for lightweight PVs, this work sets the stage for future research and paves the way toward practical implementation of alloy‐engineered 2D semiconductor solar technologies.