Flexible thermoelectric (TE) devices can generate electricity by harvesting low-grade heat from curved surfaces, which has great potential in the energy supply of flexible electronic and wearable sensing. Extensive research has focused on flexible TE materials based on conductive polymers due to their lightweight, but it is a huge challenge to obtain high performance and regulate conductivity type comparable to inorganic TE materials. Here, we report n-type Ag 2 Se/single-walled carbon nanotubes hybrid film with a high power factor ∼1030.7 µW m −1 K −2 and excellent flexibility at room temperature. Excellent mechanical and TE properties can be attributed to its network and nano-bridge structure. A TE prototype composed of six leg generates a voltage and a maximum output power of 24.8 mV and 725 nW respectively at a temperature gradient of 30 K. Our results provide insight into the design and fabrication of high-performance flexible hybrid films.

The hydrogel-based printing strategy was proposed to fabricate the high-performance flexible thermoelectric generators with the high-power density, where the stable water-locking network can limit the fluidity of the pastes.

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In this paper, a bending test of a precast ultra-high-performance concrete (UHPC) diaphragm slab was carried out. The test revealed that the flexural failure process of specimens under the action of a positive bending moment can be divided into three stages: the elastic, crack-propagation, and yield stages. The first stiffness reduction of the structure was caused by cracks at the bottom of the diaphragm slab, while the second stiffness drop resulted from the yielding of the bottom longitudinal rebars. During the loading process, the ultimate bearing capacity was 3.75 times higher than the design load value (150 kN vs. 40 kN). Additionally, a nonlinear finite element model was established using Abaqus software validated by the test and exploiting parameter analysis. Based on this model, the initial crack stress of the actual slab was determined to be 5.12 MPa. Parameter analysis indicated that the shear strength of the diaphragm slab was stronger than the flexural strength, and the diaphragm slab’s bearing capacity could be improved by increasing the ratio of bottom longitudinal reinforcement. This research confirmed that the new UHPC diaphragm slab used in Guangzhou Smart City is safe, and it also helped the design of similar UHPC slabs for utility tunnels.

Bi 2 Te 3 thin films grown the substrate with 80 nm in diameter have been prepared by using magnetron sputtering technique. The structure of thin films was determined by X-ray diffraction experiments. The average grain size and particle size in these powers were measured by the line profile analysis method of X-ray diffraction patterns and by scan electron microscopy, respectively. The thin films were investigated by using SEM measurements. The results indicate that Bi 2 Te 3 alloys could be potentially important TE materials for many applications, especially for prolonged TE device operation at high temperatures, such as for recovery of waste heat from automobile, aircrafts, and power plants due to their superiorphysical properties, including the ability of operating at high temperature/high power conditions, high mechanical strength and stability, and radiation hardness.