CN-121974387-A - Method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step

Abstract

The invention relates to a method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step, belonging to the technical field of semiconductor material preparation. The method comprises the steps of dropwise adding a sodium hydroxide aqueous solution into a stannous chloride aqueous solution at room temperature under stirring until the pH value is 12.5-13.5 to form a mixed solution system, applying intermittent ultrasonic waves to the mixed solution system to perform intermittent ultrasonic treatment so as to induce direct nucleation and growth of stannous oxide and synchronously remove chlorine impurities, carrying out solid-liquid separation, and drying solids to obtain the low-chlorine fine-particle-size stannous oxide. According to the invention, through the periodic action of intermittent ultrasonic work-stopping, nucleation and growth regulation are promoted by cavitation, and meanwhile, dynamic conditions are provided for diffusion and desorption of chloride ions, so that the cooperative regulation and control of stannous oxide particle size refinement and deep dechlorination are realized, high-temperature steps or repeated washing are not needed, the process is simple and efficient, the conditions are mild, and the controllable preparation of the high-performance stannous oxide material can be realized.

Inventors

• LI SHIQIONGCHUN
• ZHANG LIBO
• Fu Mingge
• XIA HONGYING

Assignees

• 昆明理工大学

Dates

Publication Date

20260505

Application Date

20260210

Claims (5)

1. 1. A method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step is characterized by comprising the following specific steps: (1) Dropwise adding a sodium hydroxide aqueous solution into a stannous chloride aqueous solution at room temperature under stirring until the pH value is 12.5-13.5 to form a mixed solution system; (2) Intermittent ultrasonic treatment is carried out on the mixed solution system by applying intermittent ultrasonic waves to induce the direct nucleation and growth of stannous oxide and synchronously remove chlorine impurities, solid-liquid separation is carried out, and the solid is dried to obtain the stannous oxide with low chlorine and fine particle size.
2. 2. The method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step according to claim 1, wherein the concentration of stannous chloride solution in the step (1) is 0.1-0.5 mol/L, the concentration of sodium hydroxide solution is 1.0-2.0 mol/L, the dropping rate of sodium hydroxide solution is 100-150 mL/min, and the stirring rate is 200-300 rpm.
3. 3. The method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step according to claim 1, wherein the intermittent ultrasonic waves in the step (2) are periodically turned on and off, and the ratio of ultrasonic working time to intermittent stopping time in a single period is 1:1-3.
4. 4. The method for synthesizing high-quality stannous oxide by one-step intermittent ultrasonic reinforcement according to claim 3, wherein the ultrasonic frequency is 20-40 kHz, the power density is 5-20W/mL, and the total time of intermittent ultrasonic treatment is 10-30 min.
5. 5. The method for synthesizing high-quality stannous oxide by one step through intermittent ultrasonic reinforcement according to claim 1, wherein the chlorine impurity content in the stannous oxide in the step (3) is lower than 0.03%, and the median particle size D 50 is 9.3-10.4 mu m.

Description

Method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step Technical Field The invention relates to a method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step, belonging to the technical field of semiconductor material preparation. Background Stannous oxide (SnO) is used as a narrow-bandgap (2.5-3.4 eV) p-type semiconductor material, and has wide application prospects in the fields of lithium ion batteries, gas sensors, photocatalysis and the like. The performance core index (such as sensitivity and catalytic activity) is highly dependent on the particle size of the material and the chlorine impurity content. Smaller particle sizes provide higher specific surface area and shorter carrier transport paths, while residual chlorine impurities (derived primarily from stannous chloride precursors) can severely impair carrier lifetime and electron conductivity. Industry standards therefore require that the chlorine content of high-end use SnO be less than 0.03%. The development of a synthetic method capable of synchronously realizing grain refinement and deep dechlorination is a key of technical upgrading. At present, the conventional two-step method (precursor synthesis+high temperature heat conversion) commonly adopted in industry is mature, but has the inherent defects that the high temperature step is easy to induce Ostwald ripening, so that product particles coarsen (often more than 30 mu m), agglomerate and have wide particle size distribution, and meanwhile, the chlorine-containing intermediate inevitably formed in the precursor stage is coated or doped into crystal lattices, so that chlorine impurities are difficult to remove in the subsequent step, and a large amount of repeated washing is needed to meet the standard of chlorine content <0.03%, so that the cost and environmental protection pressure are increased. The patent application published under number CN108777250a, after formation of the precursor by acid-base neutralization, assisted by continuous ultrasonic or heat treatment, prepares large-size (> 200 μm) single crystals SnO, which emphasizes the effect of ultrasonic or thermal conversion on crystal growth, but aims at obtaining large-size single crystals instead of refined particles, and does not solve the problem of chlorine residues introduced by stannous chloride precursors. In addition, the patent application with publication number CN117225399a discloses the use of continuous ultrasonic method to prepare SnO particles rapidly and as artificial metalloprotease, which proves the effectiveness of ultrasonic method in synthesizing SnO with specific morphology, but the continuous ultrasonic mode adopted is mainly aimed at rapid nucleation and mixing, and does not discuss the influence of the ultrasonic method on the chlorine content of the product, nor involves the cooperative regulation and control of particle size and purity. Patent CN106966426B reports a complex method for preparing nano porous SnO by using porous alumina as a template and combining high-temperature roasting and ultrasonic treatment, which aims to improve the electrochemical performance of the nano porous SnO. The process has complicated steps, needs to use a template agent and high-temperature inert atmosphere for protection, and the final ultrasonic treatment is only used for dispersion, is not a core synthesis driving force, and is not optimized for chlorine content control. In summary, the prior art ultrasound applications have focused on promoting reactions, aiding dispersion, or inducing crystal growth. Disclosure of Invention Aiming at the problems that chlorine impurities are wrapped or doped into crystal lattices and difficult to remove in subsequent steps due to the unavoidable formation of chlorine-containing intermediates in the existing preparation of stannous oxide, the invention provides a method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step. The invention solves the contradiction that granularity refinement and deep dechlorination are difficult to cooperatively optimize in the traditional continuous ultrasonic method by accurately modulating ultrasonic energy in the time dimension. A method for synthesizing high-quality stannous oxide by intermittent ultrasonic reinforcement in one step comprises the following specific steps: (1) Dropwise adding a sodium hydroxide aqueous solution into a stannous chloride aqueous solution at room temperature under stirring until the pH value is 12.5-13.5 to form a mixed solution system; (2) Intermittent ultrasonic treatment is carried out on the mixed solution system by applying intermittent ultrasonic waves to induce the direct nucleation and growth of stannous oxide and synchronously remove chlorine impurities, solid-liquid separation is carried out, and the solid is dried to obtain the stannous oxide with low chlorine and fine pa