Title: Fabrication and Multifunctional Regulations of Magnetic Nanomaterials

Speaker: Prof. Yanglong Hou, Peking University

Date: 2020-10-23 15:00

Location: ROOM 4-112, Chemistry Building

Abstract：

Magnetic nanomaterials (MNMs) have attracted great interests in the past few decades due to their unique properties and novel physical effects resulted from nanoscale. To understand the fundamental behavior of nanomagnetism and develop relevant potential applications, various preparation routes have been explored to produce MNMs with desired features and structures, among which chemical synthesis process, especially high-temperature organic liquid phase method, plays an indispensable role in which the microstructures and physical/chemical properties of MNMs can be tuned by controlling the reaction conditions such as precursor, surfactant, solvent, reaction temperature or time, protection atmosphere, etc. In this talk, we first introduce the fundamental of high-temperature organic liquid phase method, and present recent progress on the synthesis of various of MNMs, including monocomponent nanostructures (like metals, metal alloys, metal oxides/carbides) and multicomponent nanostructures (heterostructures and exchange-coupled nanomagnets). Particularly, the latter type not only retains the intrinsic functionalities from each single component, but also possesses the synergistic properties that benefitted from interfacial coupling, improving magnetic, optical or catalytic features. After that we will discuss the multifunctional regulations of MNMs in biomedicine and catalysis. Except of conventional MNMs, i.e. Fe₃O₄, one kind of representative iron carbides, have exhibited multifunctional properties. On the one hand, iron carbide NPs hold magnetic characteristic, can be employed as magnetic courtpart for as contract agents for T₂-weighted MRI and photoacoustic imaging (PAI) even for photothermal therapy (PTT) under NIR irradiation for ablating tumors effectively. To enhance cancer therapeutic efficiency, anticancer drug doxorubicin is loaded into bovine serum albumin coated iron carbide NPs, combining PTT with chemotherapy. Such nanoplatform can respond to NIR and acidic environments, and exhibit burst drug release. On the other hand, one kind of iron carbides, Fe₅C₂ NPs exhibited excellent catalytic performance for the Fischer−Tropsch synthesis, either in efficiency or selectivity. In summary, we overview the rational design, fabrications of magnetic nanomaterials, and give perspectives in great potential applications of these materials in biomedicine and nanocatalysis.