Synthesis Of Cu₂O/reduced Graphene Oxide Nanocomposites And Their Photoelectric Response Application

Cuprous oxide,as a P type semiconductor material,has many advantages,such as narrow band gap,easy preparation and non-toxic.It has broad application prospects in photoelectric detection,solar cell and photocatalytic degradation.Although Cu₂O has many advantages,the poor electrical property of Cu₂O is averse to the separation ofphotogenerated carriers,which restricts the application of Cu₂O in the field of optoelectronic devices.Nanomaterials have many special properties,such as quantum size effect,surface and interface effect and macroscopic tunneling effect.The nanomaterials with different morphologies may show different properties.Therefore,the Cu₂O materials of two morphologies of nanoparticles and nanowires are studied in this paper.In order to further improve the photogenerated carrier separation efficiency of Cu₂O,we introduced rGO as the electron transport layer,and synthesized the Cu₂O/rGO composites with good electrical properties,and studied the photoelectric response characteristics of the composites.In this paper,Cu₂O nanoparticles and Cu₂O/rGO nanoparticle composites,Cu₂O nanowires and Cu₂O/rGO nanowire composites were synthesized by wet reduction and hydrothermal methods respectively.Then we use X-ray diffraction?XRD?spectroscopy,scanning electron microscopy?SEM?measureing crystal structure and morphology of the materials;at the same time using UV-Vis diffuse reflectance spectroscopy?UV-vis?,fluorescence spectroscopy?PL?on the optical properties of materials characterization.Finally,the photoelectric response device was prepared by using interdigital electrode under the spraying method,and the photoelectric response ability was tested under the light?532nm?condition.The main research results of this paper are summarized as follows:?1?The characterization of Cu₂O nanoparticles and Cu₂O nanowires.The results of XRD and SEM results show that the diffraction peak of Cu₂O nanoparticles is in accordance with the Cu₂O standard PDF card.Its morphology is a cubic structure with a size of 50-200nm and the distribution is uniform.The diffraction peak of Cu₂O nanowires is also in line with the standard PDF card.Its morphology is linear,the diameter is about 100-200nm and the length is micrometer.The experimental results show the successful synthesis of Cu₂O nanoparticles and nanowires.?2?The characterization of Cu₂O/rGO nanoparticles composites and Cu₂O/rGO nanowires composites.From the SEM diagram,we can see that Cu₂O nanoparticles are attached to the rGO and the morphology and size are uniform.The Cu₂O nanowires are also uniformly grown on the rGO,indicating the successful synthesis of the two morphologies.In the UV-vis spectrum,the Cu₂O/rGO nanoparticles composite exhibits a higher absorption strength.In the PL spectrum,the fluorescence intensity of the Cu₂O/rGO nanoparticles composite is obviously weakened and appearing the quenching phenomenon.This is due to the enhancement of the separation efficiency of the photogenerated carrier of the composites,indicating that rGO inhibits the recombination of the photoelectron-hole pair.The UV-vis and PL spectra of the Cu₂O/rGO nanowires composites also showed the same properties as the Cu₂O/rGO nanoparticles composite,which showed that the introduction of rGO improving the carrier mobility of the Cu₂O nanowires.?3?The performance analysis of photoelectric response device.The results show that the switching ratio of the Cu₂O nanoparticles?the ratio of the photocurrent to the dark current?is 1.14,while the switching ratio of the Cu₂O/rGO nano particle composite device is 3.25,which is obviously improved.It shows that the electrical properties of the Cu₂O nanoparticles are enhanced after the introduction of rGO.The switching ratio of the Cu₂O nanowire device is 1.90,and the switching ratio of the Cu₂O/rGO nanowire composite device is 5.80,and there is a significant increase in the comparison.It shows that the electrical properties of the Cu₂O nanowires are enhanced after the addition of rGO.In summary,two kinds of Cu₂O nanomaterials with different morphologies and their composites with rGO have been synthesized.The composites show good electrical properties,which provide a new idea for the design of photoelectric response devices.