Method for preparing rare-earth layered hydroxide with self-sacrificing template method

Abstract

The invention discloses a method for preparing a rare-earth layered hydroxide Gd2(OH)4SO4.nH2O with a self-sacrificing template method. The method comprises the following steps: (1) uniformly mixing gadolinium nitrate hexahydrate in deionized water for preparing a gadolinium nitrate (Gd(NO3)3) solution with the Gd<3+> concentration of 0.03-0.20mol / L; (2) regulating the pH value of the solution to be 6.5-8.5, continuously stirring to obtain uniform turbid liquid, and reacting to obtain a product; (3) aging the product to room temperature, performing centrifugal separation, and drying to obtain self-sacrificing template phase Gd2(OH)5NO3.nH2O solid powder; (4) uniformly mixing a (NH4)2SO4 solution with the Gd2(OH)5NO3.nH2O solid powder according to certain ratio, and reacting under sealed condition so as to obtain a reaction product; and (5) cooling the reaction product to room temperature, performing centrifugal separation, and drying, thereby obtaining the rare-earth layered hydroxide Gd2(OH)4SO4.nH2O. The preparation method disclosed by the invention is simple, the reaction process is stable, the cost is low, and the product has uniform morphology and excellent dispersion property.

Description

Technical field: [0001] The invention belongs to the technical field of material science, and in particular relates to a method for preparing rare earth layered hydroxide Gd by a self-sacrificing template method. 2 (OH) 4 SO 4 ·nH 2 O's method. Background technique: [0002] Layered compounds have been widely studied and applied in many fields due to their unique layered structure, interlayer ion exchangeability, exfoliation and variable chemical ratio. For example, it can be used as an adsorbent to selectively adsorb certain transition metals; it can be used to eliminate harmful toluene, chlorobenzene and other organic carcinogens in the environment; it can obtain layered nanocomposites with photochromic functions (will have different functions) The photoactive guest molecule is introduced into the interlayer of layered materials); through exfoliation / self-assembly and ion exchange, the porous composite material prepared with layered manganese oxide as a precursor exhib...

AI Technical Summary

Problems solved by technology

However, the precipitant used in the precipitation method such as hexamethylenetetramine (HMT, (CH 2 ) 6 N 4 ) has the disadvantages of slow hydrolysis at room temperature, easy formation of formaldehyde and its derivatives in the air at high temperature, which reduces the yield of precipitation reaction, etc.

Although the hydrothermal method overcomes the above-mentioned shortcomings of the precipitation method, and has the advantages of high product purity and low pollution, the reaction process under hydrothermal conditions is the combination of rare earth ions, sulfate ions and hydroxyl groups, and precipitates after reaching the saturated solubility product. The reaction process requires a lot of energy, and the stability of the reaction process is poor

And the above two methods obtained Gd 2 (OH) 4 SO 4 ·nH 2 O has a relatively large degree of agglomeration in morphology and poor dispersion

Images