Nitrogen oxide remediation through metal–organic frameworks with bi-functional absorption and photocatalytic characteristics

In the population increase and growing industrialization framework, NOx (NO and NO2) arises among the most important air pollutants responsible for various health and environmental conditions. Metal-organic frameworks, MOFs, are promising materials for NOx remediation. This study investigates the removal of nitrogen oxides (NOx) using metal–organic frameworks (MOFs). MOFs UiO-66, UiO-66-NH2, MIL-125, and MIL-125-NH2 were synthesized and characterized. The surface area of the MOFs was quantified, showing values like 1118 m2/g for UiO-66-NH2 and 1424 m2/g for MIL-125-NH2. The NOx removal efficiency using the NH2 functionalized MOFs reached 100 % efficiency under UV light. Moreover, the immobilization of MIL-125-NH2 in carrageenan/alginate matrices was investigated, maintaining significant NOx reduction capabilities ~ 80 %. This work also emphasizes the potential of MOFs by combining adsorptive and photocatalytic properties, providing insights into NOx capture and transformation mechanisms, and proposing a viable approach for sustainable air remediation technologies. This work paves the way for the successful ap- plications of MOFs and MOF-modified membranes for air pollution mitigation.