Porphyrin-based MOFs as heterogeneous photocatalysts for the eradication of organic pollutants and toxins

Water and air pollution are among the major environmental challenges of this era. Waste management, economic sustainable development and renewable energy are unavoidable concomitant considerations. Over the past five years, nanosized metal-organic frameworks (nano-MOFs) have been developed for the elimination of pollutants in wet media and air-born toxins using the highly efficient reactive oxygen species (ROS) of type I (H2O2, center dot OH, O-2(center dot-)) and of type II (O-1(2)). The ROS are catalytically and efficiently generated through photosensitization, and porphyrins and metalloporphyrins are pigments of choice for this purpose. This short review summarizes the fundamentals of ROS generation by porphyrin-based nano-MOFs (mainly through the formation of ROS type II) and their composites (leading to ROS type I), which includes energy and electron transfer processes, and their applications in these environmental issues.