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.