Advanced hematite nanomaterials for newly emerging applications.

Because of the combined merits of rich physicochemical properties, abundance, low toxicity, etc. , hematite (α-Fe 2 O 3 ), one of the most chemically stable compounds based on the transition metal element iron, is endowed with multifunctionalities and has steadily been a research hotspot for decades. Very recently, advanced α-Fe 2 O 3 materials have also been developed for applications in some cutting-edge fields. To reflect this trend, the latest progress in developing α-Fe 2 O 3 materials for newly emerging applications is reviewed with a particular focus on the relationship between composition/nanostructure-induced electronic structure modulation and practical performance. Moreover, perspectives on the critical challenges as well as opportunities for future development of diverse functionalities are also discussed. We believe that this timely review will not only stimulate further increasing interest in α-Fe 2 O 3 materials but also provide a profound understanding and insight into the rational design of other materials based on transition metal elements for various applications.