Photonic Crystal Based Radiochromic Film for Visualizing the Spatial Dose Distribution of Electron Beams

Electron-beam (e-beam) technology plays a crucial role in high-dose (MGy) irradiation applications, which heavily rely on high irradiation efficiency and uniform dose distribution. However, the immediate visualization of precise e-beam dose and spatial dose distribution is challenging due to high-throughput flux and strong electron scattering. Herein, a wide dose-response range (0-3.75 MGy) and high spatial resolution (<100 μm) e-beam dosimetry based on photonic crystal (PC) polymer films is developed. The diffraction peak of the PC film demonstrates a continuous blue shift within the visible light wavelength range as the dose increases. This phenomenon is attributed to the gradual collapse of the inverse opal structure under irradiation. The naked-eye readable dosimeter shows excellent pre-and post-irradiation stability, demonstrating remarkable resistance to environmental factors such as temperature fluctuations and ultraviolet exposure. Notably, the dosimeter can detect e-beam scattering clearly when using a metal mask for radiation shielding. This work provided valuable insights into the radiation degradation behavior of PC structures under high-dose e-beam irradiation, while simultaneously offering a novel perspective for MGy-level e-beam dose and spatial distribution detection.