CN-116479441-B - Preparation of BiOX by lattice desalination method and application of BiOX in electrocatalytic halogen element production

Abstract

The application discloses a method for preparing BiOX by a lattice desalination method and application of the BiOX in producing halogen simple substance by electrocatalytic reaction. In a first aspect of the application, a lattice desalination method is provided for preparing BiOX, comprising the steps of electrocatalytic bismuth-based layered material topology lattice desalination in an electrolyte, in situ phase inversion to produce fluffy platy nanoplatelets. The precursor material is bismuth-based layered material with shared space between alkali metal/alkaline earth metal and bismuth element, and the bismuth element and the alkali metal/alkaline earth metal element contained in the bismuth-based layered material are shared space, so that under the charging condition, the material can interact with electrolyte to release alkali metal or alkaline earth metal ions in crystal lattice, and phase change occurs to grow into fluffy flaky BiOX nano-sheets. The nano-sheet has a fully exposed active interface, and unsaturated halogen vacancies in the coordination lattice are beneficial to realizing high-efficiency and stable electrocatalytic production of free halogen simple substance.

Inventors

• CHEN HONG
• FENG XUEZHEN

Assignees

• 南方科技大学

Dates

Publication Date

20260512

Application Date

20230417

Claims (4)

1. 1. The method for producing the halogen simple substance through electrocatalytic operation is characterized in that an electrocatalytic system is adopted to carry out electrocatalytic operation on electrolyte to produce the halogen simple substance, the electrocatalytic system comprises a working electrode and a counter electrode, the working electrode contains an active material, the active material comprises BiOX nano sheets, the BiOX nano sheets are prepared through a lattice desalination method, the lattice desalination method comprises the steps of carrying out topology lattice desalination on an electrocatalytic bismuth-based layered material M a Bi b O c X d in the electrolyte, carrying out in-situ phase transformation to generate fluffy sheet-shaped BiOX nano sheets, the electrolyte is electrolyte containing halogen X ions and contains ions of the same halogen element X as the halogen element X in the BiOX nano sheets, M is at least one element of alkali metal and alkaline earth metal, the bismuth-based layered material M a Bi b O c X d meets the conditions of a '+2a' +3b=2c+d, a 'is the relative quantity of alkali metal in M, a' +a 'and a' is not negative, a is 1-2, b is 1-3, and b is 1-4, d is 1-2.
2. 2. The method of claim 1, wherein the operating voltage of the lattice desalination method is 10-25 vvs.rhe and/or the time of the lattice desalination method is 1-16 h.
3. 3. The method of claim 1, wherein the electrocatalytic bismuth-based layered material M a Bi b O c X d topologically desalting comprises the steps of: preparing an electrode slurry comprising the bismuth-based layered material into a working electrode of an electrocatalytic system; And after the electrocatalytic system works, topological lattice desalination of the bismuth-based layered material M a Bi b O c X d occurs on the working electrode.
4. 4. The method of claim 1, wherein the electrocatalytic system is a photovoltaic-coupled electrocatalytic system.

Description

Preparation of BiOX by lattice desalination method and application of BiOX in electrocatalytic halogen element production Technical Field The application relates to the technical electrocatalytic field, in particular to a method for preparing BiOX by a lattice desalination method and application of the BiOX in electrocatalytic halogen element production. Background Free chlorine, a type of chlorine in the form of hypochlorous acid (HClO), hypochlorite ions (ClO -) and dissolved elemental chlorine (Cl 2), is widely used in daily life and in many important industrial processes such as disinfection products, synthesis of organic polymers, pharmaceutical production, wastewater treatment, etc. The industrial production of free chlorine is mainly electrolysis of sodium chloride, and research data show that the annual yield of free chlorine exceeds 7500 ten thousand tons worldwide, and the electricity consumption of each ton of chlorine is about 2200-2600 kW.h. This means that the existing free chlorine production has difficulty in meeting the requirements of energy conservation and environmental protection for the requirements of industrial sodium chloride and power consumption. Therefore, there is a need for improvements in electrolytic processes that reduce resource consumption and energy consumption problems by suitable technical means. Sea water is a rich and sustainable natural brine source, has the characteristics of concentrated environment and huge reserves, and simultaneously has sufficient sunlight at sea, which means that light energy is used as main power and has higher feasibility. Therefore, the photovoltaic coupling electrocatalytic system using seawater as the raw material of the electrolyte is an ideal way for producing active free chlorine economically and conveniently. However, to address the shortcomings in terms of resources and energy consumption, one critical issue of this system is how to provide highly selective electrocatalytically free chlorine producing, and stable electrode materials. Disclosure of Invention The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the application provides an application of a lattice desalination method for preparing BiOX and an electrocatalytic halogen-producing simple substance. In a first aspect of the present application, there is provided a lattice desalination process for preparing BiOX, comprising the steps of: Electrocatalytic bismuth-based layered material M aBibOcXd is subjected to topological lattice desalination in electrolyte, and in-situ phase inversion is carried out to generate fluffy sheet-shaped BiOX nano-sheets; Wherein M is at least one element of alkali metal and alkaline earth metal. The preparation method provided by the embodiment of the application has at least the following beneficial effects: The precursor material related in the preparation method is bismuth-based layered material M aBibOcXd with shared space between alkali metal/alkaline earth metal and bismuth element, and due to the layered structure and the shared space between bismuth element and alkali metal/alkaline earth metal element, lattice desalination phase conversion reaction occurs under the charging condition, specifically, the material can interact with electrolyte to release alkali metal or alkaline earth metal ions in lattice, phase change occurs, and the BiOX nano-sheet grows into fluffy sheet. The prepared fluffy flaky BiOX nano-sheet has a fully exposed active interface, unsaturated halogen vacancies in a coordination lattice are active sites for generating free halogen simple substances by oxidation, and the fluffy flaky BiOX nano-sheet has the performance of generating the free halogen simple substances by electrocatalytic action in a liquid phase containing halogen ions. Based on the autoxidation of lattice halogen and the migration supplement of ions in liquid phase, the fluffy flaky BiOX nano-sheet material is used for electrocatalytic halogen ion-containing liquid phase, and the high-efficiency and stable electrocatalytic free halogen simple substance production performance can be realized, so that the material is recycled. Meanwhile, the preparation method is simple, raw materials are easy to obtain, the price is low, the preparation method is easy to realize, and the preparation method is convenient for industrial large-scale production and application. Bismuth-based layered material M aBibOcXd satisfies a '+2a″+3b=2c+d, where a' is the relative amount of alkali metal in M, a″ is the relative amount of alkaline earth metal in M, a '+a″ =a, and neither a' nor a″ is negative. In some embodiments of the application, a is 1-2. In some embodiments of the application, b is 1-3. In some embodiments of the application, c is 1 to 4. In some embodiments of the application, d is 1-2. In some embodiments of the present application, c is 1 to 4 and d is 1 to 2. In some embodiments of the present appli