Oxygen modified nitrogen carbide and preparation method and application thereof
阅读说明：本技术 一种氧改性碳化氮及其制备方法及其应用 (Oxygen modified nitrogen carbide and preparation method and application thereof ) 是由 罗才武 张涛 刘永 谢超 于 2019-11-22 设计创作，主要内容包括：本发明公开了一种氧改性碳化氮的制备方法,包括以下步骤：将三聚氰胺在520-600℃下保温1-6h,得到g-C<Sub>3</Sub>N<Sub>4</Sub>；将g-C<Sub>3</Sub>N<Sub>4</Sub>与去离子水混合后进行水热反应,得到水热处理g-C<Sub>3</Sub>N<Sub>4</Sub>；将水热处理g-C<Sub>3</Sub>N<Sub>4</Sub>在450-600℃并保温1-6h,得到氧改性碳化氮。本发明通过水热处理和高温焙烧连续处理,对g-C<Sub>3</Sub>N<Sub>4</Sub>进行二次“氧”裁剪,得到高比表面积的氧改性碳化氮,且制备过程中不添加任何化学试剂,具有操作简单、成本低、绿色环保的特点。本发明制备出的氧改性碳化氮在降解水中有机污染物时,无论是在黑暗条件下还是在光照条件下,降解效果非常显著。(The invention discloses a preparation method of oxygen modified nitrogen carbide, which comprises the following steps: the melamine is insulated for 1 to 6 hours at the temperature of 520-600 ℃ to obtain g-C 3 N 4 (ii) a G to C 3 N 4 Mixing with deionized water, and performing hydrothermal reaction to obtain hydrothermally treated g-C 3 N 4 (ii) a Hydrothermally treating g-C 3 N 4 And keeping the temperature for 1-6h at the temperature of 450-600 ℃ to obtain the oxygen modified carbonized nitrogen. The invention carries out continuous treatment on g-C by hydrothermal treatment and high-temperature roasting 3 N 4 Performing secondary oxygen cutting to obtain the product with high specific surface areaThe nitrogen carbide is modified by oxygen, and no chemical reagent is added in the preparation process, so that the method has the characteristics of simple operation, low cost and environmental protection. When the oxygen modified nitrogen carbide prepared by the method is used for degrading organic pollutants in water, the degradation effect is very obvious no matter under dark conditions or under illumination conditions.)
1. The preparation method of the oxygen modified nitrogen carbide is characterized by comprising the following steps:
s1, the melamine is preserved for 1-6h at the temperature of 520-600 ℃ to obtain g-C3N4；
S2 preparation of g-C from S13N4Mixing with deionized water, and performing hydrothermal reaction to obtain hydrothermally treated g-C3N4；
S3, hydrothermally treating g-C3N4Placing the mixture in a covered crucible, and roasting the mixture for 1 to 6 hours at the temperature of 450-600 ℃ to obtain the oxygen modified nitrogen carbide;
wherein g-C is hydrothermally treated3N4The mass to volume ratio of the crucible is 0.10-0.18 g: 50 mL.
2. The oxygen-modified g-C of claim 13N4The preparation method is characterized in that the hydrothermal reaction temperature in S2 is 160-200 ℃ and the time is 1-10 h.
3. The oxygen-modified g-C of claim 13N4Is characterized in that g-C in S23N4And is detached fromThe mass ratio of the sub-water is 1: 10-100.
4. The oxygen-modified g-C of claim 13N4The preparation method is characterized in that after the hydrothermal reaction in S2 is finished, the reaction liquid is cooled to room temperature, washed and dried to obtain the hydrothermal treatment g-C3N4。
5. An oxygen modified nitrogen carbide produced by the method of claim 1.
6. Use of the oxygen modified nitrogen carbide of claim 5 in a fenton-like reaction.
Technical Field
The invention belongs to the technical field of advanced oxidation, and particularly relates to a preparation method and application of oxygen modified nitrogen carbide.
Background
Graphite phase nitrogen carbide (g-C)3N4) Is a non-metal semiconductor, has the advantages of acid/alkali resistance, low cost, low toxicity and the like, and is greatly interested by the majority of researchers. Currently, research on it is mainly focused on the degradation of various pollutants such as organic pollutants in water under visible light. In order to expand the range of applications more widely, some researchers supported metals or metal oxides on the surface of the metal oxide support by H2O2The purpose of efficiently degrading organic pollutants under dark and illumination conditions is achieved. Nevertheless, metal ions exist in these cases without exception, and during the process of degrading pollutants, the metal ions are easy to lose, thereby easily causing secondary pollution of water, and doping with external non-metal elements is a good choice for solving the problem.
Compared with doping common non-metal elements (such as B, F, P, S and the like), the O is doped with g-C3N4Has the advantages of no toxicity, rich source, easy preparation, etc. To date, the oxygen-doped nitrogen carbide preparation process is mainly carried out under liquid phase conditions, and comprises a single oxidant oxidation, such as H, according to different oxidation modes2O2(chem. Commun.,2012,48:12017-3(Dalton trans.2018,47:6772-6778, etc.); mixed oxidant oxidation, e.g. concentrated HNO3+H2SO4(adv.Mater.2016,28:6940-6945, etc.), HNO3+KMnO4(chem.Eur.J.2015,21:6241-6246, etc.). Besides environmental pollution, the method also has the problems of high toxicity, high cost, complex operation and the like. Water is directly used as an oxygen source (ChemSusChem.2018,11: 700-708; appl.Catal.B: environ.2018,221: 9-16; J.colloid Interf.Sci.2016,476:193-199 and the like), although the preparation process is green and environment-friendly, the specific surface area of the prepared material is less than 60m at most2And/g, the function is limited, and the application is severely limited. Therefore, it is necessary to develop a new method for preparing oxygen-doped nitrogen carbide.
Disclosure of Invention
The invention provides a preparation method of oxygen modified nitrogen carbide, which solves the problems in the prior art.
The first purpose of the invention is to provide a preparation method of oxygen modified nitrogen carbide, which comprises the following steps:
s1, the melamine is preserved for 1-6h at the temperature of 520-600 ℃ to obtain g-C3N4；
S2 preparation of g-C from S13N4Mixing with deionized water, and performing hydrothermal reaction to obtain hydrothermally treated g-C3N4；
S3, hydrothermally treating g-C3N4Placing the mixture in a covered crucible, and roasting the mixture for 1 to 6 hours at the temperature of 450-600 ℃ to obtain the oxygen modified nitrogen carbide;
wherein g-C is hydrothermally treated3N4The mass to volume ratio of the crucible is 0.10-0.18 g: 50 mL.
Preferably, the hydrothermal reaction temperature in S2 is 160-200 ℃ and the time is 1-10 h.
Preferably, g-C in S23N4The mass ratio of the deionized water to the deionized water is 1: 10-100.
Preferably, after completion of the hydrothermal reaction in S2, the reaction solution is cooled to room temperature, washed and dried to obtain hydrothermally treated g-C3N4。
It is a second object of the present invention to provide an oxygen modified nitrogen carbide prepared according to the above method.
The third purpose of the invention is to provide the application of the oxygen modified nitrogen carbide in Fenton-like reaction.
Compared with the prior art, the invention has the beneficial effects that:
the invention carries out continuous treatment on g-C by hydrothermal treatment and high-temperature roasting3N4And the oxygen-modified nitrogen carbide with high specific surface area is obtained by secondary oxygen cutting, and no chemical reagent is added in the preparation process of the material, so that the method has the advantages of simplicity in operation, low cost, environmental friendliness and the like.
When the oxygen modified nitrogen carbide prepared by the method is used for degrading organic pollutants in water, the degradation effect is very obvious no matter under dark conditions or under illumination conditions.
Detailed Description
In order to make the technical solutions of the present invention better understood and enable those skilled in the art to practice the present invention, the following embodiments are further described, but the present invention is not limited to the following embodiments.
The experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.