Silkworm-chrysalis-shaped PbS quantum dot/graphene composite material and preparation method thereof

Abstract

The invention belongs to the field of nanometer materials and nanometer technologies and in particular relates to a silkworm-chrysalis-shaped PbS quantum dot / graphene composite material and a preparation method thereof. The preparation method comprises the steps of evenly dispersing graphene oxide into ethylene glycol to form graphene oxide-ethylene glycol dispersion liquid; adding lead nitrate powder into the graphene oxide-ethylene glycol dispersion liquid to obtain lead nitrate-graphene-ethylene glycol dispersion liquid; dissolving sodium sulphide into ethylene glycol to form sodium sulphide-ethylene glycol solution; processing the lead nitrate-graphene-ethylene glycol dispersion liquid through ultrasound, adding the sodium sulphide-ethylene glycol solution into the lead nitrate-graphene-ethylene glycol drop by drop and mechanically stirring to obtain PbS quantum dot-graphene dispersion liquid after reaction; then centrifugally separating, washing and drying to obtain the PbS quantum dot / graphene composite material. The prepared PbS quantum dot / graphene composite material is of a silkworm-chrysalis-shaped three-dimension structure, even in quantum dot particle size and excellent in gas-sensitive property to ammonia gas in a room temperature and a low temperature.

Description

technical field [0001] The invention belongs to the field of nanomaterials and nanotechnology, and in particular relates to a "chrysalis-like" PbS quantum dot / graphene composite material and a preparation method thereof. Background technique [0002] As we all know, ammonia gas will be used in large quantities in industrial production, and at the same time, it has certain harmful effects on the human body and the environment, so the leakage detection of ammonia gas is particularly important. At present, the alarm for ammonia leakage is mainly achieved by installing gas detection sensors. At present, most of the materials of ammonia sensors are mainly metal semiconductor oxides, but they have the disadvantages of high working temperature, high energy consumption, poor stability and safety, etc. With its large specific surface area and excellent physical and chemical properties, graphene has received widespread attention in the field of gas sensors. It is considered to be a g...

AI Technical Summary

Problems solved by technology

However, there are still many challenges for graphene gas-sensing materials. The main problems are: (1) graphene itself will have certain defects, and the corresponding stability of the device will be seriously affected; (2) due to the electrons in the graphene two-dimensional plane The movement of graphene is less hindered, making it difficult for gas molecules to desorb, and the recovery time of the device is too long, some as long as several hours. Therefore, the functionalization of graphene is particularly important.

Images