Blue Oxidation: Properties, Preparation and Diverse Applications

1. Optical Properties: It has excellent light absorption and emission performance. Some copper-containing blue oxides have a photoluminescence quantum efficiency exceeding 30% in the blue light band (450 - 480 nm), which is beneficial for applications such as blue LEDs and fluorescent labeling.

2. Electrical Properties: Some possess semiconductor properties. For example, cuprous oxide (Cu₂O) can reach an electron mobility of 100 - 300 cm²/V·s at room temperature, making it available for electronic devices.

3. Catalytic Properties: It has abundant surface active sites and high catalytic activity. For instance, cobalt blue oxide (Co₃O₄) can catalyze the degradation of organic dyes at a fast rate, promoting chemical reactions.

1. Chemical Precipitation Method: The metal salt solution reacts with the precipitating agent, and by controlling parameters such as pH and temperature, blue oxide precipitates are obtained. For example, when preparing cuprous oxide, a copper hydroxide precursor is first prepared and then calcined. Under appropriate conditions, the product has high purity and uniform particle size.

2. Sol - Gel Method: Using metal alkoxides or inorganic salts as raw materials, through hydrolysis and condensation to form a sol and then gelation, and finally obtaining the product by high-temperature sintering. When preparing titanium blue oxide, tetrabutyl titanate is selected, and by controlling the temperature and humidity, the obtained gel has excellent crystallinity and good dispersibility after sintering.

3. Physical Vapor Deposition Method: In a high-temperature and high-vacuum environment, metal atoms are vaporized and react with oxygen to deposit blue oxide films. For example, when preparing zinc oxide (ZnO) blue variant films, the parameters of magnetron sputtering can be adjusted to obtain the desired films.

IV. Application Fields of Blue Oxidation

1. Electronic Field: In the blue LED industry, it is used as a phosphor conversion material to improve the color rendering index; it is also used in transistor manufacturing to enhance device performance. For example, Cu₂O-based transistors have the potential to break through the bottleneck.

2. Catalytic Field: It is used to degrade organic pollutants in water pollution treatment and participates in photocatalytic water splitting to produce hydrogen, contributing to clean energy preparation.

3. Environmental Protection Field: It is made into gas sensors to monitor air pollutants; it is also used in soil remediation to adsorb heavy metal ions.