Preparation Of Controllable Cupric Oxide Nanoparticles Using Water-Soluble Poly (Amic Acid) Salts As The Intermediate

Nanoparticles and nanostructured materials have received considerable attention. Copper oxide nanoparticles are of special interest because of their potential applications in areas such as catalyst, gas sensors, chemical cell, thermosensor, photosensor, magnetic storage, and thermoelectric materials. Of equal importance from a fundamental viewpoint is the magnetism of the Cu (Ⅱ) ions in various environments because of its relevance to high-temperature superconductivity of several CuO-based ceramics.The properties of nanoparticles are greatly dependent on the shape, size, composition and the structure of the crystal. Scientists have done much research on the preparation of metal nanoparticles, and now could successfully fabricate the particles which have given shape and controllable size. The methods to synthesize CuO nanomaterials are diverse, such as electrochemical deposition, alcohothermal, thermal decomposition, solid-state reaction, microwave irradiation, sol-gel and microemulsion. The broad adoptive method is adding organic surfactant or polymer between the processes to realize the monodisperse of the nanoparticles and to control the shape and size. This means can prepare nanoparticles with different kinds of perfect shape in large range of size.But, in most cases, the developed methods just suitable for one or slim number metals and often only for a specific shape of the preparation of metal nanoparticles. Sometimes improper operation may also lead to the aggregation of nanoparticles, the loss of its good performance. Another method have a big problem that is the experiment require to accurately control between the processes of nucleus formation and growth, because the structure of the original crystal nucleus determined the final shape of the particles. The experiment have proved that little perturbation motion could make big change in shape and size, and the particles' size is smaller the influence is more outstanding. So the sensitivity of the experiment makes the repeatability to be a big problem. Another problem is few polymers could apply in preparing particles. Up to now few polymer applying successfully.Recently we develop a simple way to fabricate copper oxide nanoparticles. Polyamide acid as a specific molecular structure makes the polyamide acid in the polyimide hybrid materials prepared by nanometal has played a huge role. Polyamide acid is a kind of polymer which have amido bond and carboxyl group. These active functional groups could form complex intensively with kinds of cations. In our experiment, the water-soluble polyamide acid as the intermediate cross linked with Cu2+ in the solution-phase, and then the complex is made to be ultra-thin film, at last the complex growth,aggregate and thermal-cure in the solid-phase. With the method, we can prepare monodisperse copper oxide nanoparticles. The crystal growth in the anisotropic environment and the growth is restricted in the ultra-thin film that is propitious to fabric nanoparticles with different shape and size. In the solid-phase the experiment under effective control and decrease the sensitivity. Further more, in the experiment we don't need to add any other surfactant and stabilizing agent. Up to now Using this method, we prepared a monodispersed CuO nanoparticles. Little work has been published concerning the preparation of CuO nanoparticles by means of the polyamide acid as the intermediate.Experimental results show that this method can be prepared well dispersed cubic nanoparticles, the particle size are about 100nm.