Phase Engineering of Nanomaterials: Metal Nanomaterials

Phase is a fundamental structural parameter that distinguishes the atomic arrangement in materials. The recent advancement in phase engineering of nanomaterials (PEN) has witnessed the discovery and intriguing physicochemical properties of a number of unconventional phases in metal nanomaterials, enabling their promising applications in catalysis, optics, and so on. With the aid of advanced characterization techniques and theoretical calculations, phase engineering of metal nanomaterials has made significant progress in terms of precisely controlled synthesis, phase transformation, and phase-dependent property studies. This review summarizes the recent progress of PEN with a focus on metal nanomaterials. First, we introduce various synthetic strategies to prepare unconventional-phase metal nanomaterials, including monometallic and multimetallic nanomaterials. Second, we discuss methods to realize phase transformation of metallic nanomaterials. Then, we demonstrate various phase-dependent properties and applications of metal nanomaterials. Last, current challenges and exciting opportunities in the phase engineering of metal nanomaterials are discussed.