Phase Control in Monometallic and Alloy Nanomaterials

Metal nanomaterials with unconventional phases have been recently developed with a variety of methods and exhibit novel and attractive properties such as high activities for various catalytic reactions and magnetic properties. In this review, we discuss the progress and the trends in strategies for synthesis, crystal structure, and properties of phase-controlled metal nanomaterials in terms of elements and the combination of alloys. We begin with a brief introduction of the anomalous phase behavior derived from the nanosize effect and general crystal structures observed in metal nanomaterials. Then, phase control in monometallic nanomaterials with respect to each element and alloy nanomaterials classified into three types based on their crystal structures is discussed. In the end, all the content introduced in this review is summarized, and challenges for advanced phase control are discussed.