A kind of carbon nitride quantum dot/oxide nanofiber composite photocatalytic material and preparation method thereof

Abstract

The invention belongs to the technical field of preparation of composite photocatalytic materials, in particular to a carbon nitride quantum dot / oxide nanofiber composite photocatalytic material and a preparation method thereof. The preparation method of the present invention includes: preparing a precursor solution from a polymer, a solvent, and a metal salt, then electrospinning and calcining the precursor solution to obtain oxide nanofibers, and preparing carbon nitride nanosheets, and finally making the oxide nanofibers The fiber and the carbon nitride nanosheets are respectively placed at the outlet end and the inlet end of the tube furnace, and the inlet end is heat-treated under the condition of transporting in an inert atmosphere to obtain a composite photocatalytic material. The thermal exfoliation in-situ deposition method adopted in the present invention realizes the preparation and recombination of carbon nitride quantum dots in one step. Compared with the existing hydrothermal method and mechanical mixing method, the uniformity of recombination and the efficiency of recombination are significantly improved, and the preparation The structure of the composite material is stable, which solves the problem that quantum dots are not easy to composite, and the method is simple, easy and low in cost.

Description

Technical field [0001] The present invention belongs to the preparation of composite photocatalytic materials, and in particular, the present invention relates to a carbon nitride quantum dot / oxide nanofiber complex photocatalytic material and a preparation method thereof. Background technique [0002] Semiconductor photocatalytic technology, as a green environmental protection technology, has an important value in environmental pollution control and clean energy development. In numerous photocatalytic materials, carbon nitride (G-C 3 N 4 ) Because it has the advantages of suitable band structure, good stability, low cost, safe and non-toxic, etc., has been widely studied and concerned in recent years. However, a single component of G-C 3 N 4 There is a problem of low solar utilization rate, high carrier composite rate, resulting in G-C 3 N 4 The photocatalytic activity is low, thereby limiting its wide application. Therefore, G-C 3 N 4 Modify to improve its photocatalytic perf...

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Problems solved by technology

[0004] The Chinese invention patent with the authorized announcement number CN106268900B discloses a g-C 3 N 4 Quantum dot sensitized AgVO 3 Preparation method of nanowires; literature "Monodisperse g-C 3 N 4 Synthesis of quantum dot-modified one-dimensional rod-like BiPO4 crystallites and its mechanism for enhancing photocatalytic activity” reported a g-C 3 N 4 One-dimensional rod-like BiPO modified with quantum dots 4 Photocatalysts (see ChineseJournal of Inorganic Chemistry 32(2016) 1246-1254), these methods usually first synthesize g-C in the preparation process 3 N 4 Quantum dots, and then prepare the final composite photocatalyst by hydrothermal method, mechanical mixing method and other methods. Among them, the hydrothermal method requires high experimental equipment, the mechanical mixing method takes a long time, the composite efficiency is low, and the distribution of quantum dots after composite uneven, easy to fall off

In addition, the one-dimensional oxides synthesized by these methods are mostly nanowires and nanorods with relatively small length and diameter, which are still powder materials from a macroscopic point of view, and there are problems of difficult separation and recovery during use and high recycling costs.

[0005] Literature "Hybridization of g-C 3 N 4 quantum dots with 1D branched TiO 2 Fiber for efficient visible light-driven photocatalytic hydrogen generation" reported the use of electrospinning technology and alkaline hydrothermal method to prepare branched TiO 2 nanofibers were then deposited on TiO by chemical vapor deposition 2 Nanofiber surface attachment g-C 3 N 4 Quantum dots (see International Journal of HydrogenEnergy 45(2020) 13994-14005), although this method can realize g-C 3 N 4 The preparation and recombination of quantum dots on the surface of nanofibers, but the prepared g-C 3 N 4 Quantum dots have poor dispersion and low loading

In addition, branched TiO was prepared by alkaline hydrothermal method 2 Nanofibers, the reaction conditions are harsh, and the requirements for experimental equipment are high. At the same time, the prepared fibers have problems such as poor continuity and low strength.

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