Controilable Synthesis And Applications Of Iron-based Micro/nanomaterials

Iron based Micro/nanomaterials have been used in many fields, andthey have also exhibited very broad potential in these fields, even otherhot fields. Thus, many researchers focus their studies in the synthesis andapplication of the iron based Micro/nanomaterials. In the recent decades,the simple, green methods are studied for the controlled synthesize theoutstanding iron based Micro/nanomaterials with unique morphologies.Naturally, the growth rules of such Micro/nanomaterials are alsoinvestigated very deep to develop the effective application of theMicro/nanomaterials. In this work, we use the iron oxide as the object. Byusing of the different methods, the iron based Micro/nanomaterials withdifferent morphologies are obtained. In order to contribute to thesynthesis of the iron based Micro/nanomaterials, we also studied theformation mechanism of these materials. The as-prepared materials arealso applied in ORR, be welcome, the as-prepared materials show verygood application in ORR. The works are exhibited as follows in detail:1. A simple quasi-one-step template-free route is reported to preparehierarchical Fe₃O₄-Co₃O₄yolk-shell nanostructures. These high porousarchitectures, with the diameter about2μm, were assembled by Co3O4flower-like shell and Fe₃O₄sphere rattle-core. A series of experimentswith different conditions was carried into execution to determine the keyfactors in this typical solvothermal synthesis that leads to the formation ofthe yolk–shell products of Fe₃O₄-Co₃O₄aggregates, and a possiblegrowth mechanism is also proposed. Furthermore, they exhibit excellentelectrocatalytic ORR performance. Namely, the half-wave potential ofFe₃O₄-Co₃O₄yolk-shell nanostructures is about5and80mVpositive-shifted than that of Co3O4and Fe₃O₄nanoparticles, and thecurrent density of O₂reduction is much higher. Moreover, it is nearly4electrons process. Thus, they may be a kind of efficient and cheap metal-free cathodic electrocatalyst for DMFCs.2. By using of the egg white, the Fe₃O₄/C thin films are prepared inthis part. In the reaction process, different reagents are used to break thebonds in protein. We have done many experiments to study the influenceof time, temperature, concentration of reactants and so on. After theseinvestigations, the films with different thick and size are obtained. Toenlarge the application of this new method, we also conclude the reactionfactors in this work.