Cuprous Telluride Based Semiconductor Nanocrystals: Controlled Synthesis And Properties Research

Cuprous Telluride Based semiconductor nanocrystals have been extensively investigated for their applications in photovoltaic and photothermal. For their good ionic conductivity, thermoelectric, and near infrared(NIR) localized surface plasmon resonance(LSPR) effects. For industrial applications, easy-synthetic route and well-controlled properties of Cuprous Telluride Based semiconductor nanocrystals are critical. In this work, we synthesized three kinds of Cuprous Telluride Based semiconductor nanocrystals(Cu2-x Te, Cu1.75 Te, and Cu7Te5) with different non-stoichiometry by aqueous and organic solution methods. In addition, we investigated the shape control and their near-infrared LSPR properties based on shape control synthesis.1. In aqueous solution, we used Te single-crystalline nanorods as starting materials and in-situ transform them to be Cu2-x Te nanorods with ethanol medium. Microstructures and compositions of Cu2-x Te nanorods were characterized by transmission electron microscopy(TEM), high-resolution transmission electron microscopy(HRTEM), scanning electron microscopy(SEM), and X-ray diffraction(XRD) technique. The UV-Vis-NIR spectroscopy and photo-thermal conversion test of Cu2-x Te nanorods showed they have good absorptions of near-infrared hight due to their LSPR effect in this region. It was observed that due to the Cu2+, hydrazine and Na BH4 addition, the shapes could be tailored.2. In organic solution, we synthesized two kinds of Cuprous Telluride Based semiconductor nanocrystals(namely Cu1.75 Te and Cu7Te5) under low temperature. Different morphologies of as-prepared Cu1.75 Te, were observed based on the mediation from the surfactants of DDT(dichlorodiphenyltrichloroethane). DDT plays an important role in the self-assembly of Cu1.75 Te nanorods and size-control of Cu7Te5 nanocuboids. The XRD, TEM, HRTEM, and SEM techniques were used to characterize the Cu1.75 Te nanorods and Cu7Te5 nanocuboids. From the Uv-Vis-NIR spectroscopy and photo-thermal conversion test we concluded that Cu1.75 Te nanorods show better absorption than Cu7Te5 nanocuboids in the near infrared spectrum.3. Further, the comparison of photo-thermal conversion efficiency among these three Cuprous Telluride Based semiconductor nanocrystals indicates that Cu2-x Te nanorods illustrate better absorption than Cu1.75 Te nanorods, and Cu1.75 Te nanorods show better absorption than Cu7Te5 nanocuboids. Our work also gives the conclusion that Cu7Te5 nanocuboids could be used to assembly into large scale films with good uniformity and compactness.