Functional nanomaterials for selective uranium recovery from seawater: Material design, extraction properties and mechanisms

Environmental pollution and resource shortage are two major problems in the current world. Nuclear energy, a green energy with high energy density, has attracted extensive attention and development of the world. As an important nuclear fuel, U(VI) is used in most of the world's nuclear power plants. The ocean contains a large amount of low-concentration uranium, so selective enriching U(VI) from seawater is of great significance to the development of nuclear energy and stable energy supply. In this review, the recent research progress of functional materials with potential applications for U(VI) extraction from seawater, including COFs, MOFs, polymers and porous carbon, are summarized and compared. Combined with batch experiments, advanced spectroscopic techniques and theoretical calculations, the mechanism of U(VI) extraction from seawater using various materials as adsorbents, photocatalysts and electrocatalysts is expounded. The practical application of the materials in U(VI) extraction from seawater is discussed mainly from the aspects of sorption capacity, selectivity, stability and applicability. In the end, the current challenges and opportunities of functional materials for U(VI) extraction from seawater are summarized and prospected, to provide guidance for the design of new functional materials in future.