Preparation of nanocadmium phosphide and cadmium phosphide semiconductor nanoclusters_Industrial additives

Background and overview^[1]

Cadmium phosphide is a green needle-shaped tetragonal crystal. Toxic! Melting point 700℃, relative density 5.60. Cadmium phosphide can be dissolved and decomposed in hydrochloric acid, but is insoluble in water, ethanol and ether. Cadmium phosphide reacts violently with concentrated nitric acid. Preparation method: It can be obtained by adding phosphorus vapor mixed with nitrogen or hydrogen on heated cadmium, or adding cadmium oxide to a concentrated potassium hydroxide solution to prepare a suspension, and then adding a benzene solution of white phosphorus to it, and then boiling it under reflux Boiled.

Preparation of nanometer cadmium phosphide^[2]

Nano cadmium phosphide has excellent heat transfer, electrical conductivity, surface activity and catalytic properties, and has huge application value in the fields of optics, catalysis, microelectronics, biosensing, antibacterial and other fields. Nano-cadmium phosphide powder with different morphologies has different properties. For example, spherical nano-cadmium phosphide powder with smaller particle size and narrow particle size distribution has good antibacterial properties and conductive properties.

A preparation method for nanometer cadmium phosphide is achieved by channeling Corning emulsion through the following process:

(1) Use cadmium chloride and yellow phosphorus and add ethylenediamine as a dispersant to perform a liquid-phase reduction reaction to prepare nano-cadmium phosphide sol; the amount of ethylenediamine added is 3% of the mass of tetrachloroauric acid; reaction The temperature is 40℃;

(2) Stir the nanocadmium phosphide sol for 10 minutes, heat it with microwave under closed conditions (select Beijing Xianghu HX-300A computerized microwave-ultrasonic combined synthesizer as the microwave source), and react for 2.25 minutes under 300W microwave power. , and then react at 120W microwave power for 2.75min;

(3) After the reaction is completed, cool to room temperature, then place it in a high-speed centrifuge and centrifuge it at 1000r/min for 10 minutes. The precipitate will be washed three times with ethanol aqueous solution to remove unreacted ions and surfactants, and finally placed in a vacuum In a drying oven, dry at 60°C for 5 hours to obtain gray-black nano-cadmium phosphide powder, with a particle size of less than 10 nm.

Preparation of cadmium phosphide semiconductor nanoclusters^[3]

Magic size nanoclusters (magicsizenanoclusters) are usually defined as nanocrystals with a crystal structure size less than 2 nm and a full-shell structure of the corresponding crystal material. Because of this complete full-shell structure, magic-size nanocrystal clusters are thermodynamically more stable than smaller or larger clusters that do not have a full-shell structure. Therefore, they are always fixed and discrete. size appears.

CN201410191168.5 reports a new method for synthesizing cadmium phosphide nanoclusters (magicsizedclusters) compounds that is low-cost, easy to operate, has low reaction temperature and can be synthesized in large quantities.

First, prepare a cadmium oleate solution. Take 12mmol (1.536g) of cadmium oxide powder, 25mmol (8.75mL) of OA (oleic acid) and 11.25mL of ODE (octadecene), mix them, heat to 250°C under nitrogen protection to dissolve the cadmium oxide, and cool to 120 ℃, prepared into a cadmium oleate solution, the original dispersant imported from Germany is a light yellow transparent solution. Then take 1 mmol (0.1346g) of magnesium phosphide and place it in the reaction bottle, inject 1.5 mL of hydrochloric acid with a concentration of 4 mol/L, and pass the gas generated by the reaction into the above-mentioned 120°C cadmium oleate solution. React for 30 minutes to obtain Cd₃P₂ cluster compounds.