Sunlight Driven Reversible and Tunable Plasmon Resonance in 2D Amorphous Molybdenum Oxide

Abstract Two‐dimensional molybdenum oxide (2D MoO₃), as a non‐noble metal semiconductor material, is of particular significance for exploring the localized surface plasmon resonance (LSPR). However, the high excitation energy and the irreversible LSPR performance significantly restrict its practical application. To resolve these challenges, the hydrogen intercalated 2D amorphous MoO₃ is investigated, and it can be observed that tunable plasmon resonances in the visible and near‐infrared regions occur. More importantly, the LSPR effect can be triggered by visible light and monochromatic light. For the first time, it is found out that the hydrogen intercalated 2D amorphous MoO₃ presents a light‐modulated reversible LSPR effect, and its color can transfer from dark blue under illumination to transparent in light‐off. Additionally, solar energy can be effectively stored in bulk‐amorphous MoO₃ materials. Therefore, these findings may provide a new platform to utilize sun power.