Bi2te3-based alloy hexagonal nanosheets were synthesized by gas induced reduction (GIR) method with independent innovation. It was found that the growth of Bi2Te3-based alloy hexagonal nanosheets was based on a selective adsorption mechanism. It was found for the first time that Cu could effectively prevent the oxidation of Bi2Te3. The theoretical calculation shows that the reason is that Cu doping can improve the stability of the system, and Cu is a substitute for doping rather than intercalation. The thermoelectric properties of Bi2Te3 (Cu0.05Bi2Te3-xSex) doped with Cu and Se were studied. It was found that the conductivity increased with the increase of Se content, and the Seebeck coefficient was the opposite. This is mainly due to the rise of carrier concentration caused by Se blending. The maximum power factor of the x=0.3 sample is 17.6 µWcm-1K-2, which is 10% higher than that without Se doping. When Cu0.05Bi2Te2.7Se0.3 was selected as the base sample, it was found that adding Bi nanopowder could promote sintering. When the addition amount was less than 1%, the conductivity was slightly increased, and the Seebeck coefficient was higher than that of the sample without Bi. The main reason is the scattering of carriers by microvoids.
The addition of Bi significantly increased the power factor, and the maximum power factor of the sample with 2%Bi reached 30.3 µWcm-1K-2, which increased by 75% compared with the model without Bi, which is a better value reported for N-type Bi2Te3-based thermoelectric materials. Bi2Te3 nanorods, nanosheets, and nano-flowers were prepared by microwave-assisted wet chemistry. The power factor of the Bi2Te3 nano-flower sample after hot pressing is higher, reaching 17.3 Wcm-1K-2. The morphology of Bi2Te3 and Bi2Se3 nanostructures can be regulated by changing the acidity and alkalinity of the precursor solution. Bi2Te3 nanoflowers and Bi2Se3 nano-flowers were mixed and hot-pressed to make blocks of Bi2Se3Te3-y (y=1, 2, 3). With the increase of Z, the conductivity of the sample increased, and the absolute value of the Seebeck coefficient decreased significantly, mainly due to the increase in carrier concentration. The y=1 selection has the maximum power factor of 24.5µWcm-1K-2 (369K), which is higher than the power factor of 20µWcm-1K-2 (20 µwcm-1k-2). The same component material after high-energy ball milling by Ren Zhifeng's research group indicates that the process is encouraging. If you are looking for high quality, high purity and cost-effective bismuth telluride, or if you require the latest price of bismuth telluride, please feel free to email contact mis-asia.
