Eu(OH)3 and Eu(OH)3-based nanostructures: Synthesis, properties, and uses

In recent years, there has been great progress in the development of metal hydroxides as they possess distinctive structures, high adsorption capacity, etc. These metal hydroxides have shown excellent performance as catalysts in energy, environmental, and biological applications. Similarly, rare-earth hydroxide (RE(OH)3) for instance, europium hydroxide (Eu(OH)3) have been fabricated using different methods for various uses. In general, Eu(OH)3 nanostructures possess good electronic, optical, catalytic, and chemical properties which mainly arise from electron transitions within the 4f shell. It possesses a hexagonal crystal structure with a space group of P63/m. However, due to the hexagonal structure of Eu(OH)3, the binding state of Eu3+ can be influenced and in turn control the performance of the material. Therefore, this review comprises the synthesis and development of Eu(OH)3 and Eu(OH)3-based nanomaterials. The properties of Eu(OH)3 and Eu(OH)3-based nanostructures have been discussed. The synthesis and use of Eu(OH)3 and Eu(OH)3-based nanomaterials in biological and environmental applications have also been compiled and discussed. However, there are still research gaps that have not been explored to facilitate the development of Eu(OH)3 and Eu(OH)3-based nanostructures. Therefore, future prospects have been suggested in this review.