Iron triad (Fe, Co, Ni) nanomaterials: Structural design, functionalization and their applications

The structure and the composition are two key factors that influence the physical, chemical, and other properties of materials. Correspondingly, structural design and functionalization with inorganic or organic materials provide efficient routes to enhancing some properties. Herein, iron triad nanomaterials, with a wide range of applications in energy, environment and other fields, were chosen as the target materials. This paper reviews various approaches for designing three typical structures (hollow and porous, ultrathin two-dimensional, and complex three-dimensional structures) of iron triad nanomaterials with high specific surface areas as well as their feasible functionalization for special purposes. Furthermore, some amazing work in recent years is introduced and discussed, especially in the energy field including energy transfer, conversion and storage, and in the environment field, including the adsorption and removal of harmful inorganic ions and organic pollutants. This review aims at developing potential applications of the nanomaterials using structural adjustment and functionalization to overcome their intrinsic shortcomings and enhance their performance.