Solid-state thermoelectric technology offers a promising solution for converting waste heat to useful electrical power. Both high operating temperature and high figure of merit zT are desirable for high-efficiency thermoelectric power generation. Here we report a high zT of ∼1.5 at 1,200 K for the p-type FeNbSb heavy-band half-Heusler alloys. High content of heavier Hf dopant simultaneously optimizes the electrical power factor and suppresses thermal conductivity. Both the enhanced point-defect and electron–phonon scatterings contribute to a significant reduction in the lattice thermal conductivity. An eight couple prototype thermoelectric module exhibits a high conversion efficiency of 6.2% and a high power density of 2.2 W cm−2 at a temperature difference of 655 K. These findings highlight the optimization strategy for heavy-band thermoelectric materials and demonstrate a realistic prospect of high-temperature thermoelectric modules based on half-Heusler alloys with low cost, excellent mechanical robustness and stability.

Iodine-doped Cu2 Se shows a significantly improved thermoelectric performance during phase transitions by electron and phonon critical scattering, leading to a dramatic increase in zT by a factor of 3-7 times culminating in zT values of 2.3 at 400 K.

High efficiency Bi2Te3-based thermoelectric materials and devices with energy conversion efficiencies of up to 6.0% under a temperature gradient of 217 K.

Full-parameter optimization and energy-loss minimized integration enable a record-high efficiency of 12% in a segmented power-generating module.

Wrapping grain boundaries with rGO enhances zT by increasing thermal boundary resistance, Rκ, with minimal effect on the electronic transport.

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Diamond‐like compounds are a promising class of thermoelectric materials, very suitable for real applications. However, almost all high‐performance diamond‐like thermoelectric materials are p‐type semiconductors. The lack of high‐performance n‐type diamond‐like thermoelectric materials greatly restricts the fabrication of diamond‐like material‐based modules and their real applications. In this work, it is revealed that n‐type AgInSe2 diamond‐like compound has intrinsically high thermoelectric performance with a figure of merit (zT) of 1.1 at 900 K, comparable to the best p‐type diamond‐like thermoelectric materials reported before. Such high zT is mainly due to the ultralow lattice thermal conductivity, which is fundamentally limited by the low‐frequency Ag‐Se “cluster vibrations,” as confirmed by ab initio lattice dynamic calculations. Doping Cd at Ag sites significantly improves the thermoelectric performance in the low and medium temperature ranges. By using such high‐performance n‐type AgInSe2‐based compounds, the diamond‐like thermoelectric module has been fabricated for the first time. An output power of 0.06 W under a temperature difference of 520 K between the two ends of the module is obtained. This work opens a new window for the applications using the diamond‐like thermoelectric materials.

Background. Moxibustion has a therapeutic effect of reducing swelling and relieving pain in patients with rheumatoid arthritis (RA) but its mechanism is uncertain. Objective. To evaluate the effect of moxibustion on serum levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in patients with RA and to explore the possible mechanism of moxibustion. Methods. This study involved 46 RA patients who had fulfilled the inclusion criteria and were randomly assigned to a treatment group and a control group in an equal ratio. The control group was treated with methotrexate or leflunomide, while the treatment group received methotrexate or leflunomide and moxibustion at ST 36 (Zusanli), BL 23 (Shenshu), and Ashi points. Patients’ clinical symptoms, RA-associated serum markers, and serum levels of TNF-α, IL-1β, HIF-1α, and VEGF were compared in the two groups before and after intervention. Statistical analysis was performed using SPSS 21.0 statistical software. Results. 37 of 46 RA patients eventually completed the whole treatment course. Compared with the control group, the treatment group significantly improved the clinical symptoms (P<0.05) but with no significant differences in RA-associated serum markers (P>0.05). There were significant differences in TNF-α and IL-1β among the groups after 8 weeks of treatment (P<0.05). HIF-1α and VEGF were decreased in the treatment group after therapy (P<0.05). VEGF was reduced in the control group (P<0.05), while HIF-1α was not significantly improved (P>0.05). The reductions of HIF-1α and VEGF in the treatment group were superior to the control group (P<0.05). Conclusions. Moxibustion enhanced the anti-inflammatory and analgesic effects of conventional medicine and can enhance the effect of conventional medicine, downregulating HIF-1α/VEGF contents to inhibit angiogenesis.