Crystalline Porous Materials for Gaseous Iodine Capture: A Comprehensive Review.

The growing reliance on nuclear energy necessitates efficient strategies for managing spent nuclear fuel, particularly the capture of volatile radioactive iodine, which poses significant environmental and health risks. Crystalline porous materials have emerged as promising candidates for iodine adsorption due to their high surface areas, tunable porosity, and abundant active sites. This review comprehensively summarizes recent advancements in the design and application of four classes of crystalline porous materials for iodine capture: metal-organic frameworks, covalent organic frameworks, hydrogen-bonded organic frameworks, and porous organic cages. The discussion focuses on key adsorption mechanisms, structural modifications, and functionalization strategies that enhance iodine adsorption capacity, retention, and recyclability. While significant progress has been made, challenges remain in scaling up synthesis, improving stability under industrial conditions, and achieving cost-effective large-scale applications. Future research should emphasize on scalable synthesis, industrial validation, and development of multifunctional adsorbents with enhanced selectivity and reusability. This review provides insights into the rational design of next-generation porous materials for efficient iodine capture, contributing to advancements in nuclear waste management and environmental sustainability.